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Android example source code file (Paint.java)

This example Android source code file (Paint.java) is included in the DevDaily.com "Java Source Code Warehouse" project. The intent of this project is to help you "Learn Android by Example" TM.

Java - Android tags/keywords

align, android, arrayindexoutofboundsexception, cap, colorfilter, fontmetrics, fontmetricsint, join, maskfilter, paint, rasterizer, rect, string, style, text, xfermode

The Paint.java Android example source code

/*
 * Copyright (C) 2006 The Android Open Source Project
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package android.graphics;

import android.text.TextUtils;
import android.text.SpannableString;
import android.text.SpannedString;
import android.text.GraphicsOperations;

/**
 * The Paint class holds the style and color information about how to draw
 * geometries, text and bitmaps.
 */
public class Paint {

    /*package*/ int     mNativePaint;
    private ColorFilter mColorFilter;
    private MaskFilter  mMaskFilter;
    private PathEffect  mPathEffect;
    private Rasterizer  mRasterizer;
    private Shader      mShader;
    private Typeface    mTypeface;
    private Xfermode    mXfermode;

    private boolean     mHasCompatScaling;
    private float       mCompatScaling;
    private float       mInvCompatScaling;
    
    private static final Style[] sStyleArray = {
        Style.FILL, Style.STROKE, Style.FILL_AND_STROKE
    };
    private static final Cap[] sCapArray = {
        Cap.BUTT, Cap.ROUND, Cap.SQUARE
    };
    private static final Join[] sJoinArray = {
        Join.MITER, Join.ROUND, Join.BEVEL
    };
    private static final Align[] sAlignArray = {
        Align.LEFT, Align.CENTER, Align.RIGHT
    };

    /** bit mask for the flag enabling antialiasing */
    public static final int ANTI_ALIAS_FLAG     = 0x01;
    /** bit mask for the flag enabling bitmap filtering */
    public static final int FILTER_BITMAP_FLAG  = 0x02;
    /** bit mask for the flag enabling dithering */
    public static final int DITHER_FLAG         = 0x04;
    /** bit mask for the flag enabling underline text */
    public static final int UNDERLINE_TEXT_FLAG = 0x08;
    /** bit mask for the flag enabling strike-thru text */
    public static final int STRIKE_THRU_TEXT_FLAG = 0x10;
    /** bit mask for the flag enabling fake-bold text */
    public static final int FAKE_BOLD_TEXT_FLAG = 0x20;
    /** bit mask for the flag enabling linear-text (no caching) */
    public static final int LINEAR_TEXT_FLAG    = 0x40;
    /** bit mask for the flag enabling subpixel-text */
    public static final int SUBPIXEL_TEXT_FLAG  = 0x80;
    /** bit mask for the flag enabling device kerning for text */
    public static final int DEV_KERN_TEXT_FLAG  = 0x100;

    // we use this when we first create a paint
    private static final int DEFAULT_PAINT_FLAGS = DEV_KERN_TEXT_FLAG;

    /**
     * The Style specifies if the primitive being drawn is filled,
     * stroked, or both (in the same color). The default is FILL.
     */
    public enum Style {
        /**
         * Geometry and text drawn with this style will be filled, ignoring all
         * stroke-related settings in the paint.
         */
        FILL            (0),
        /**
         * Geometry and text drawn with this style will be stroked, respecting
         * the stroke-related fields on the paint.
         */
        STROKE          (1),
        /**
         * Geometry and text drawn with this style will be both filled and
         * stroked at the same time, respecting the stroke-related fields on
         * the paint.
         */
        FILL_AND_STROKE (2);
        
        Style(int nativeInt) {
            this.nativeInt = nativeInt;
        }
        final int nativeInt;
    }

    /**
     * The Cap specifies the treatment for the beginning and ending of
     * stroked lines and paths. The default is BUTT.
     */
    public enum Cap {
        /**
         * The stroke ends with the path, and does not project beyond it.
         */
        BUTT    (0),
        /**
         * The stroke projects out as a semicircle, with the center at the
         * end of the path.
         */
        ROUND   (1),
        /**
         * The stroke projects out as a square, with the center at the end
         * of the path.
         */
        SQUARE  (2);
        
        private Cap(int nativeInt) {
            this.nativeInt = nativeInt;
        }
        final int nativeInt;
    }

    /**
     * The Join specifies the treatment where lines and curve segments
     * join on a stroked path. The default is MITER.
     */
    public enum Join {
        /**
         * The outer edges of a join meet at a sharp angle
         */
        MITER   (0),
        /**
         * The outer edges of a join meet in a circular arc.
         */
        ROUND   (1),
        /**
         * The outer edges of a join meet with a straight line
         */
        BEVEL   (2);
        
        private Join(int nativeInt) {
            this.nativeInt = nativeInt;
        }
        final int nativeInt;
    }

    /**
     * Align specifies how drawText aligns its text relative to the
     * [x,y] coordinates. The default is LEFT.
     */
    public enum Align {
        /**
         * The text is drawn to the right of the x,y origin
         */
        LEFT    (0),
        /**
         * The text is drawn centered horizontally on the x,y origin
         */
        CENTER  (1),
        /**
         * The text is drawn to the left of the x,y origin
         */
        RIGHT   (2);
        
        private Align(int nativeInt) {
            this.nativeInt = nativeInt;
        }
        final int nativeInt;
    }

    /**
     * Create a new paint with default settings.
     */
    public Paint() {
        this(0);
    }
    
    /**
     * Create a new paint with the specified flags. Use setFlags() to change
     * these after the paint is created.
     *
     * @param flags initial flag bits, as if they were passed via setFlags().
     */
    public Paint(int flags) {
        mNativePaint = native_init();
        setFlags(flags | DEFAULT_PAINT_FLAGS);
        mCompatScaling = mInvCompatScaling = 1;
    }

    /**
     * Create a new paint, initialized with the attributes in the specified
     * paint parameter.
     *
     * @param paint Existing paint used to initialized the attributes of the
     *              new paint.
     */
    public Paint(Paint paint) {
        mNativePaint = native_initWithPaint(paint.mNativePaint);
        mHasCompatScaling = paint.mHasCompatScaling;
        mCompatScaling = paint.mCompatScaling;
        mInvCompatScaling = paint.mInvCompatScaling;
    }

    /** Restores the paint to its default settings. */
    public void reset() {
        native_reset(mNativePaint);
        setFlags(DEFAULT_PAINT_FLAGS);
        mHasCompatScaling = false;
        mCompatScaling = mInvCompatScaling = 1;
    }
    
    /**
     * Copy the fields from src into this paint. This is equivalent to calling
     * get() on all of the src fields, and calling the corresponding set()
     * methods on this.
     */
    public void set(Paint src) {
        if (this != src) {
            // copy over the native settings
            native_set(mNativePaint, src.mNativePaint);
            // copy over our java settings
            mColorFilter    = src.mColorFilter;
            mMaskFilter     = src.mMaskFilter;
            mPathEffect     = src.mPathEffect;
            mRasterizer     = src.mRasterizer;
            mShader         = src.mShader;
            mTypeface       = src.mTypeface;
            mXfermode       = src.mXfermode;
            mHasCompatScaling = src.mHasCompatScaling;
            mCompatScaling    = src.mCompatScaling;
            mInvCompatScaling = src.mInvCompatScaling;
        }
    }

    /** @hide */
    public void setCompatibilityScaling(float factor) {
        if (factor == 1.0) {
            mHasCompatScaling = false;
            mCompatScaling = mInvCompatScaling = 1.0f;
        } else {
            mHasCompatScaling = true;
            mCompatScaling = factor;
            mInvCompatScaling = 1.0f/factor;
        }
    }
    
    /**
     * Return the paint's flags. Use the Flag enum to test flag values.
     *
     * @return the paint's flags (see enums ending in _Flag for bit masks)
     */
    public native int getFlags();

    /**
     * Set the paint's flags. Use the Flag enum to specific flag values.
     *
     * @param flags The new flag bits for the paint
     */
    public native void setFlags(int flags);

    /**
     * Helper for getFlags(), returning true if ANTI_ALIAS_FLAG bit is set
     * AntiAliasing smooths out the edges of what is being drawn, but is has
     * no impact on the interior of the shape. See setDither() and
     * setFilterBitmap() to affect how colors are treated.
     *
     * @return true if the antialias bit is set in the paint's flags.
     */
    public final boolean isAntiAlias() {
        return (getFlags() & ANTI_ALIAS_FLAG) != 0;
    }
    
    /**
     * Helper for setFlags(), setting or clearing the ANTI_ALIAS_FLAG bit
     * AntiAliasing smooths out the edges of what is being drawn, but is has
     * no impact on the interior of the shape. See setDither() and
     * setFilterBitmap() to affect how colors are treated.
     *
     * @param aa true to set the antialias bit in the flags, false to clear it
     */
    public native void setAntiAlias(boolean aa);
    
    /**
     * Helper for getFlags(), returning true if DITHER_FLAG bit is set
     * Dithering affects how colors that are higher precision than the device
     * are down-sampled. No dithering is generally faster, but higher precision
     * colors are just truncated down (e.g. 8888 -> 565). Dithering tries to
     * distribute the error inherent in this process, to reduce the visual
     * artifacts.
     *
     * @return true if the dithering bit is set in the paint's flags.
     */
    public final boolean isDither() {
        return (getFlags() & DITHER_FLAG) != 0;
    }
    
    /**
     * Helper for setFlags(), setting or clearing the DITHER_FLAG bit
     * Dithering affects how colors that are higher precision than the device
     * are down-sampled. No dithering is generally faster, but higher precision
     * colors are just truncated down (e.g. 8888 -> 565). Dithering tries to
     * distribute the error inherent in this process, to reduce the visual
     * artifacts.
     *
     * @param dither true to set the dithering bit in flags, false to clear it
     */
    public native void setDither(boolean dither);
    
    /**
     * Helper for getFlags(), returning true if LINEAR_TEXT_FLAG bit is set
     *
     * @return true if the lineartext bit is set in the paint's flags
     */
    public final boolean isLinearText() {
        return (getFlags() & LINEAR_TEXT_FLAG) != 0;
    }

    /**
     * Helper for setFlags(), setting or clearing the LINEAR_TEXT_FLAG bit
     *
     * @param linearText true to set the linearText bit in the paint's flags,
     *                   false to clear it.
     */
    public native void setLinearText(boolean linearText);

    /**
     * Helper for getFlags(), returning true if SUBPIXEL_TEXT_FLAG bit is set
     *
     * @return true if the subpixel bit is set in the paint's flags
     */
    public final boolean isSubpixelText() {
        return (getFlags() & SUBPIXEL_TEXT_FLAG) != 0;
    }
    
    /**
     * Helper for setFlags(), setting or clearing the SUBPIXEL_TEXT_FLAG bit
     *
     * @param subpixelText true to set the subpixelText bit in the paint's
     *                     flags, false to clear it.
     */
    public native void setSubpixelText(boolean subpixelText);
    
    /**
     * Helper for getFlags(), returning true if UNDERLINE_TEXT_FLAG bit is set
     *
     * @return true if the underlineText bit is set in the paint's flags.
     */
    public final boolean isUnderlineText() {
        return (getFlags() & UNDERLINE_TEXT_FLAG) != 0;
    }

    /**
     * Helper for setFlags(), setting or clearing the UNDERLINE_TEXT_FLAG bit
     *
     * @param underlineText true to set the underlineText bit in the paint's
     *                      flags, false to clear it.
     */
    public native void setUnderlineText(boolean underlineText);

    /**
     * Helper for getFlags(), returning true if STRIKE_THRU_TEXT_FLAG bit is set
     *
     * @return true if the strikeThruText bit is set in the paint's flags.
     */
    public final boolean isStrikeThruText() {
        return (getFlags() & STRIKE_THRU_TEXT_FLAG) != 0;
    }

    /**
     * Helper for setFlags(), setting or clearing the STRIKE_THRU_TEXT_FLAG bit
     *
     * @param strikeThruText true to set the strikeThruText bit in the paint's
     *                       flags, false to clear it.
     */
    public native void setStrikeThruText(boolean strikeThruText);

    /**
     * Helper for getFlags(), returning true if FAKE_BOLD_TEXT_FLAG bit is set
     *
     * @return true if the fakeBoldText bit is set in the paint's flags.
     */
    public final boolean isFakeBoldText() {
        return (getFlags() & FAKE_BOLD_TEXT_FLAG) != 0;
    }

    /**
     * Helper for setFlags(), setting or clearing the STRIKE_THRU_TEXT_FLAG bit
     *
     * @param fakeBoldText true to set the fakeBoldText bit in the paint's
     *                     flags, false to clear it.
     */
    public native void setFakeBoldText(boolean fakeBoldText);
    
    /**
     * Whether or not the bitmap filter is activated.
     * Filtering affects the sampling of bitmaps when they are transformed.
     * Filtering does not affect how the colors in the bitmap are converted into
     * device pixels. That is dependent on dithering and xfermodes.
     *
     * @see #setFilterBitmap(boolean) setFilterBitmap()
     */
    public final boolean isFilterBitmap() {
        return (getFlags() & FILTER_BITMAP_FLAG) != 0;
    }
    
    /**
     * Helper for setFlags(), setting or clearing the FILTER_BITMAP_FLAG bit.
     * Filtering affects the sampling of bitmaps when they are transformed.
     * Filtering does not affect how the colors in the bitmap are converted into
     * device pixels. That is dependent on dithering and xfermodes.
     * 
     * @param filter true to set the FILTER_BITMAP_FLAG bit in the paint's
     *               flags, false to clear it.
     */
    public native void setFilterBitmap(boolean filter);

    /**
     * Return the paint's style, used for controlling how primitives'
     * geometries are interpreted (except for drawBitmap, which always assumes
     * FILL_STYLE).
     *
     * @return the paint's style setting (Fill, Stroke, StrokeAndFill)
     */
    public Style getStyle() {
        return sStyleArray[native_getStyle(mNativePaint)];
    }

    /**
     * Set the paint's style, used for controlling how primitives'
     * geometries are interpreted (except for drawBitmap, which always assumes
     * Fill).
     *
     * @param style The new style to set in the paint
     */
    public void setStyle(Style style) {
        native_setStyle(mNativePaint, style.nativeInt);
    }

    /**
     * Return the paint's color. Note that the color is a 32bit value
     * containing alpha as well as r,g,b. This 32bit value is not premultiplied,
     * meaning that its alpha can be any value, regardless of the values of
     * r,g,b. See the Color class for more details.
     *
     * @return the paint's color (and alpha).
     */
    public native int getColor();

    /**
     * Set the paint's color. Note that the color is an int containing alpha
     * as well as r,g,b. This 32bit value is not premultiplied, meaning that
     * its alpha can be any value, regardless of the values of r,g,b.
     * See the Color class for more details.
     *
     * @param color The new color (including alpha) to set in the paint.
     */
    public native void setColor(int color);
    
    /**
     * Helper to getColor() that just returns the color's alpha value. This is
     * the same as calling getColor() >>> 24. It always returns a value between
     * 0 (completely transparent) and 255 (completely opaque).
     *
     * @return the alpha component of the paint's color.
     */
    public native int getAlpha();

    /**
     * Helper to setColor(), that only assigns the color's alpha value,
     * leaving its r,g,b values unchanged. Results are undefined if the alpha
     * value is outside of the range [0..255]
     *
     * @param a set the alpha component [0..255] of the paint's color.
     */
    public native void setAlpha(int a);

    /**
     * Helper to setColor(), that takes a,r,g,b and constructs the color int
     *
     * @param a The new alpha component (0..255) of the paint's color.
     * @param r The new red component (0..255) of the paint's color.
     * @param g The new green component (0..255) of the paint's color.
     * @param b The new blue component (0..255) of the paint's color.
     */
    public void setARGB(int a, int r, int g, int b) {
        setColor((a << 24) | (r << 16) | (g << 8) | b);
    }

    /**
     * Return the width for stroking.
     * <p />
     * A value of 0 strokes in hairline mode.
     * Hairlines always draws a single pixel independent of the canva's matrix.
     *
     * @return the paint's stroke width, used whenever the paint's style is
     *         Stroke or StrokeAndFill.
     */
    public native float getStrokeWidth();

    /**
     * Set the width for stroking.
     * Pass 0 to stroke in hairline mode.
     * Hairlines always draws a single pixel independent of the canva's matrix.
     *
     * @param width set the paint's stroke width, used whenever the paint's
     *              style is Stroke or StrokeAndFill.
     */
    public native void setStrokeWidth(float width);

    /**
     * Return the paint's stroke miter value. Used to control the behavior
     * of miter joins when the joins angle is sharp.
     *
     * @return the paint's miter limit, used whenever the paint's style is
     *         Stroke or StrokeAndFill.
     */
    public native float getStrokeMiter();

    /**
     * Set the paint's stroke miter value. This is used to control the behavior
     * of miter joins when the joins angle is sharp. This value must be >= 0.
     *
     * @param miter set the miter limit on the paint, used whenever the paint's
     *              style is Stroke or StrokeAndFill.
     */
    public native void setStrokeMiter(float miter);

    /**
     * Return the paint's Cap, controlling how the start and end of stroked
     * lines and paths are treated.
     *
     * @return the line cap style for the paint, used whenever the paint's
     *         style is Stroke or StrokeAndFill.
     */
    public Cap getStrokeCap() {
        return sCapArray[native_getStrokeCap(mNativePaint)];
    }

    /**
     * Set the paint's Cap.
     *
     * @param cap set the paint's line cap style, used whenever the paint's
     *            style is Stroke or StrokeAndFill.
     */
    public void setStrokeCap(Cap cap) {
        native_setStrokeCap(mNativePaint, cap.nativeInt);
    }

    /**
     * Return the paint's stroke join type.
     *
     * @return the paint's Join.
     */
    public Join getStrokeJoin() {
        return sJoinArray[native_getStrokeJoin(mNativePaint)];
    }

    /**
     * Set the paint's Join.
     *
     * @param join set the paint's Join, used whenever the paint's style is
     *             Stroke or StrokeAndFill.
     */
    public void setStrokeJoin(Join join) {
        native_setStrokeJoin(mNativePaint, join.nativeInt);
    }

    /**
     * Applies any/all effects (patheffect, stroking) to src, returning the
     * result in dst. The result is that drawing src with this paint will be
     * the same as drawing dst with a default paint (at least from the
     * geometric perspective).
     *
     * @param src input path
     * @param dst output path (may be the same as src)
     * @return    true if the path should be filled, or false if it should be
     *                 drawn with a hairline (width == 0)
     */
    public boolean getFillPath(Path src, Path dst) {
        return native_getFillPath(mNativePaint, src.ni(), dst.ni());
    }

    /**
     * Get the paint's shader object.
     *
     * @return the paint's shader (or null)
     */
    public Shader getShader() {
        return mShader;
    }

    /**
     * Set or clear the shader object.
     * <p />
     * Pass null to clear any previous shader.
     * As a convenience, the parameter passed is also returned.
     *
     * @param shader May be null. the new shader to be installed in the paint
     * @return       shader
     */
    public Shader setShader(Shader shader) {
        int shaderNative = 0;
        if (shader != null)
            shaderNative = shader.native_instance;
        native_setShader(mNativePaint, shaderNative);
        mShader = shader;
        return shader;
    }

    /**
     * Get the paint's colorfilter (maybe be null).
     *
     * @return the paint's colorfilter (maybe be null)
     */
    public ColorFilter getColorFilter() {
        return mColorFilter;
    }

    /**
     * Set or clear the paint's colorfilter, returning the parameter.
     *
     * @param filter May be null. The new filter to be installed in the paint
     * @return       filter
     */
    public ColorFilter setColorFilter(ColorFilter filter) {
        int filterNative = 0;
        if (filter != null)
            filterNative = filter.native_instance;
        native_setColorFilter(mNativePaint, filterNative);
        mColorFilter = filter;
        return filter;
    }

    /**
     * Get the paint's xfermode object.
     *
     * @return the paint's xfermode (or null)
     */
    public Xfermode getXfermode() {
        return mXfermode;
    }

    /**
     * Set or clear the xfermode object.
     * <p />
     * Pass null to clear any previous xfermode.
     * As a convenience, the parameter passed is also returned.
     *
     * @param xfermode May be null. The xfermode to be installed in the paint
     * @return         xfermode
     */
    public Xfermode setXfermode(Xfermode xfermode) {
        int xfermodeNative = 0;
        if (xfermode != null)
            xfermodeNative = xfermode.native_instance;
        native_setXfermode(mNativePaint, xfermodeNative);
        mXfermode = xfermode;
        return xfermode;
    }

    /**
     * Get the paint's patheffect object.
     *
     * @return the paint's patheffect (or null)
     */
    public PathEffect getPathEffect() {
        return mPathEffect;
    }

    /**
     * Set or clear the patheffect object.
     * <p />
     * Pass null to clear any previous patheffect.
     * As a convenience, the parameter passed is also returned.
     *
     * @param effect May be null. The patheffect to be installed in the paint
     * @return       effect
     */
    public PathEffect setPathEffect(PathEffect effect) {
        int effectNative = 0;
        if (effect != null) {
            effectNative = effect.native_instance;
        }
        native_setPathEffect(mNativePaint, effectNative);
        mPathEffect = effect;
        return effect;
    }

    /**
     * Get the paint's maskfilter object.
     *
     * @return the paint's maskfilter (or null)
     */
    public MaskFilter getMaskFilter() {
        return mMaskFilter;
    }

    /**
     * Set or clear the maskfilter object.
     * <p />
     * Pass null to clear any previous maskfilter.
     * As a convenience, the parameter passed is also returned.
     *
     * @param maskfilter May be null. The maskfilter to be installed in the
     *                   paint
     * @return           maskfilter
     */
    public MaskFilter setMaskFilter(MaskFilter maskfilter) {
        int maskfilterNative = 0;
        if (maskfilter != null) {
            maskfilterNative = maskfilter.native_instance;
        }
        native_setMaskFilter(mNativePaint, maskfilterNative);
        mMaskFilter = maskfilter;
        return maskfilter;
    }

    /**
     * Get the paint's typeface object.
     * <p />
     * The typeface object identifies which font to use when drawing or
     * measuring text.
     *
     * @return the paint's typeface (or null)
     */
    public Typeface getTypeface() {
        return mTypeface;
    }

    /**
     * Set or clear the typeface object.
     * <p />
     * Pass null to clear any previous typeface.
     * As a convenience, the parameter passed is also returned.
     *
     * @param typeface May be null. The typeface to be installed in the paint
     * @return         typeface
     */
    public Typeface setTypeface(Typeface typeface) {
        int typefaceNative = 0;
        if (typeface != null) {
            typefaceNative = typeface.native_instance;
        }
        native_setTypeface(mNativePaint, typefaceNative);
        mTypeface = typeface;
        return typeface;
    }
    
    /**
     * Get the paint's rasterizer (or null).
     * <p />
     * The raster controls/modifies how paths/text are turned into alpha masks.
     *
     * @return         the paint's rasterizer (or null)
     */
    public Rasterizer getRasterizer() {
        return mRasterizer;
    }

    /**
     * Set or clear the rasterizer object.
     * <p />
     * Pass null to clear any previous rasterizer.
     * As a convenience, the parameter passed is also returned.
     *
     * @param rasterizer May be null. The new rasterizer to be installed in
     *                   the paint.
     * @return           rasterizer
     */
    public Rasterizer setRasterizer(Rasterizer rasterizer) {
        int rasterizerNative = 0;
        if (rasterizer != null) {
            rasterizerNative = rasterizer.native_instance;
        }
        native_setRasterizer(mNativePaint, rasterizerNative);
        mRasterizer = rasterizer;
        return rasterizer;
    }
    
    /**
     * Temporary API to expose layer drawing. This draws a shadow layer below
     * the main layer, with the specified offset and color, and blur radius.
     * If radius is 0, then the shadow layer is removed.
     */
    public native void setShadowLayer(float radius, float dx, float dy,
                                      int color);

    /**
     * Temporary API to clear the shadow layer.
     */
    public void clearShadowLayer() {
        setShadowLayer(0, 0, 0, 0);
    }

    /**
     * Return the paint's Align value for drawing text. This controls how the
     * text is positioned relative to its origin. LEFT align means that all of
     * the text will be drawn to the right of its origin (i.e. the origin
     * specifieds the LEFT edge of the text) and so on.
     *
     * @return the paint's Align value for drawing text.
     */
    public Align getTextAlign() {
        return sAlignArray[native_getTextAlign(mNativePaint)];
    }

    /**
     * Set the paint's text alignment. This controls how the
     * text is positioned relative to its origin. LEFT align means that all of
     * the text will be drawn to the right of its origin (i.e. the origin
     * specifieds the LEFT edge of the text) and so on.
     *
     * @param align set the paint's Align value for drawing text.
     */
    public void setTextAlign(Align align) {
        native_setTextAlign(mNativePaint, align.nativeInt);
    }

    /**
     * Return the paint's text size.
     *
     * @return the paint's text size.
     */
    public native float getTextSize();

    /**
     * Set the paint's text size. This value must be > 0
     *
     * @param textSize set the paint's text size.
     */
    public native void setTextSize(float textSize);

    /**
     * Return the paint's horizontal scale factor for text. The default value
     * is 1.0.
     *
     * @return the paint's scale factor in X for drawing/measuring text
     */
    public native float getTextScaleX();

    /**
     * Set the paint's horizontal scale factor for text. The default value
     * is 1.0. Values > 1.0 will stretch the text wider. Values < 1.0 will
     * stretch the text narrower.
     *
     * @param scaleX set the paint's scale in X for drawing/measuring text.
     */
    public native void setTextScaleX(float scaleX);

    /**
     * Return the paint's horizontal skew factor for text. The default value
     * is 0.
     *
     * @return         the paint's skew factor in X for drawing text.
     */
    public native float getTextSkewX();

    /**
     * Set the paint's horizontal skew factor for text. The default value
     * is 0. For approximating oblique text, use values around -0.25.
     *
     * @param skewX set the paint's skew factor in X for drawing text.
     */
    public native void setTextSkewX(float skewX);

    /**
     * Return the distance above (negative) the baseline (ascent) based on the
     * current typeface and text size.
     *
     * @return the distance above (negative) the baseline (ascent) based on the
     *         current typeface and text size.
     */
    public native float ascent();

    /**
     * Return the distance below (positive) the baseline (descent) based on the
     * current typeface and text size.
     *
     * @return the distance below (positive) the baseline (descent) based on
     *         the current typeface and text size.
     */
    public native float descent();

    /**
     * Class that describes the various metrics for a font at a given text size.
     * Remember, Y values increase going down, so those values will be positive,
     * and values that measure distances going up will be negative. This class
     * is returned by getFontMetrics().
     */
    public static class FontMetrics {
        /**
         * The maximum distance above the baseline for the tallest glyph in 
         * the font at a given text size.
         */
        public float   top;
        /**
         * The recommended distance above the baseline for singled spaced text.
         */
        public float   ascent;
        /**
         * The recommended distance below the baseline for singled spaced text.
         */
        public float   descent;
        /**
         * The maximum distance below the baseline for the lowest glyph in 
         * the font at a given text size.
         */
        public float   bottom;
        /**
         * The recommended additional space to add between lines of text.
         */
        public float   leading;
    }
    
    /**
     * Return the font's recommended interline spacing, given the Paint's
     * settings for typeface, textSize, etc. If metrics is not null, return the
     * fontmetric values in it.
     *
     * @param metrics If this object is not null, its fields are filled with
     *                the appropriate values given the paint's text attributes.
     * @return the font's recommended interline spacing.
     */
    public native float getFontMetrics(FontMetrics metrics);
    
    /**
     * Allocates a new FontMetrics object, and then calls getFontMetrics(fm)
     * with it, returning the object.
     */
    public FontMetrics getFontMetrics() {
        FontMetrics fm = new FontMetrics();
        getFontMetrics(fm);
        return fm;
    }
    
    /**
     * Convenience method for callers that want to have FontMetrics values as
     * integers.
     */
    public static class FontMetricsInt {
        public int   top;
        public int   ascent;
        public int   descent;
        public int   bottom;
        public int   leading;
        
        @Override public String toString() {
            return "FontMetricsInt: top=" + top + " ascent=" + ascent +
                    " descent=" + descent + " bottom=" + bottom +
                    " leading=" + leading;
        }
    }

    /**
     * Return the font's interline spacing, given the Paint's settings for
     * typeface, textSize, etc. If metrics is not null, return the fontmetric
     * values in it. Note: all values have been converted to integers from
     * floats, in such a way has to make the answers useful for both spacing
     * and clipping. If you want more control over the rounding, call
     * getFontMetrics().
     *
     * @return the font's interline spacing.
     */
    public native int getFontMetricsInt(FontMetricsInt fmi);

    public FontMetricsInt getFontMetricsInt() {
        FontMetricsInt fm = new FontMetricsInt();
        getFontMetricsInt(fm);
        return fm;
    }
    
    /**
     * Return the recommend line spacing based on the current typeface and
     * text size.
     *
     * @return  recommend line spacing based on the current typeface and
     *          text size.
     */
    public float getFontSpacing() {
        return getFontMetrics(null);
    }

    /**
     * Return the width of the text.
     *
     * @param text  The text to measure
     * @param index The index of the first character to start measuring
     * @param count THe number of characters to measure, beginning with start
     * @return      The width of the text
     */
    public float measureText(char[] text, int index, int count) {
        if (!mHasCompatScaling) return native_measureText(text, index, count);
        final float oldSize = getTextSize();
        setTextSize(oldSize*mCompatScaling);
        float w = native_measureText(text, index, count);
        setTextSize(oldSize);
        return w*mInvCompatScaling;
    }

    private native float native_measureText(char[] text, int index, int count);
    
    /**
     * Return the width of the text.
     *
     * @param text  The text to measure
     * @param start The index of the first character to start measuring
     * @param end   1 beyond the index of the last character to measure
     * @return      The width of the text
     */
    public float measureText(String text, int start, int end) {
        if (!mHasCompatScaling) return native_measureText(text, start, end);
        final float oldSize = getTextSize();
        setTextSize(oldSize*mCompatScaling);
        float w = native_measureText(text, start, end);
        setTextSize(oldSize);
        return w*mInvCompatScaling;
    }

    private native float native_measureText(String text, int start, int end);
    
    /**
     * Return the width of the text.
     *
     * @param text  The text to measure
     * @return      The width of the text
     */
    public float measureText(String text) {
        if (!mHasCompatScaling) return native_measureText(text);
        final float oldSize = getTextSize();
        setTextSize(oldSize*mCompatScaling);
        float w = native_measureText(text);
        setTextSize(oldSize);
        return w*mInvCompatScaling;
    }

    private native float native_measureText(String text);
    
    /**
     * Return the width of the text.
     *
     * @param text  The text to measure
     * @param start The index of the first character to start measuring
     * @param end   1 beyond the index of the last character to measure
     * @return      The width of the text
     */
    public float measureText(CharSequence text, int start, int end) {
        if (text instanceof String) {
            return measureText((String)text, start, end);
        }
        if (text instanceof SpannedString ||
            text instanceof SpannableString) {
            return measureText(text.toString(), start, end);
        }
        if (text instanceof GraphicsOperations) {
            return ((GraphicsOperations)text).measureText(start, end, this);
        }

        char[] buf = TemporaryBuffer.obtain(end - start);
        TextUtils.getChars(text, start, end, buf, 0);
        float result = measureText(buf, 0, end - start);
        TemporaryBuffer.recycle(buf);
        return result;
    }
    
    /**
     * Measure the text, stopping early if the measured width exceeds maxWidth.
     * Return the number of chars that were measured, and if measuredWidth is
     * not null, return in it the actual width measured.
     *
     * @param text  The text to measure
     * @param index The offset into text to begin measuring at
     * @param count The number of maximum number of entries to measure. If count
     *              is negative, then the characters before index are measured
     *              in reverse order. This allows for measuring the end of
     *              string.
     * @param maxWidth The maximum width to accumulate.
     * @param measuredWidth Optional. If not null, returns the actual width
     *                     measured.
     * @return The number of chars that were measured. Will always be <=
     *         abs(count).
     */
    public int breakText(char[] text, int index, int count,
                                float maxWidth, float[] measuredWidth) {
        if (!mHasCompatScaling) {
            return native_breakText(text, index, count, maxWidth, measuredWidth);
        }
        final float oldSize = getTextSize();
        setTextSize(oldSize*mCompatScaling);
        int res = native_breakText(text, index, count, maxWidth*mCompatScaling,
                measuredWidth);
        setTextSize(oldSize);
        if (measuredWidth != null) measuredWidth[0] *= mInvCompatScaling;
        return res;
    }

    private native int native_breakText(char[] text, int index, int count,
                                        float maxWidth, float[] measuredWidth);

    /**
     * Measure the text, stopping early if the measured width exceeds maxWidth.
     * Return the number of chars that were measured, and if measuredWidth is
     * not null, return in it the actual width measured.
     *
     * @param text  The text to measure
     * @param start The offset into text to begin measuring at
     * @param end   The end of the text slice to measure.
     * @param measureForwards If true, measure forwards, starting at start.
     *                        Otherwise, measure backwards, starting with end.
     * @param maxWidth The maximum width to accumulate.
     * @param measuredWidth Optional. If not null, returns the actual width
     *                     measured.
     * @return The number of chars that were measured. Will always be <=
     *         abs(end - start).
     */
    public int breakText(CharSequence text, int start, int end,
                         boolean measureForwards,
                         float maxWidth, float[] measuredWidth) {
        if (start == 0 && text instanceof String && end == text.length()) {
            return breakText((String) text, measureForwards, maxWidth,
                             measuredWidth);
        }

        char[] buf = TemporaryBuffer.obtain(end - start);
        int result;

        TextUtils.getChars(text, start, end, buf, 0);

        if (measureForwards) {
            result = breakText(buf, 0, end - start, maxWidth, measuredWidth);
        } else {
            result = breakText(buf, 0, -(end - start), maxWidth, measuredWidth);
        }

        TemporaryBuffer.recycle(buf);
        return result;
    }

    /**
     * Measure the text, stopping early if the measured width exceeds maxWidth.
     * Return the number of chars that were measured, and if measuredWidth is
     * not null, return in it the actual width measured.
     *
     * @param text  The text to measure
     * @param measureForwards If true, measure forwards, starting with the
     *                        first character in the string. Otherwise,
     *                        measure backwards, starting with the
     *                        last character in the string.
     * @param maxWidth The maximum width to accumulate.
     * @param measuredWidth Optional. If not null, returns the actual width
     *                     measured.
     * @return The number of chars that were measured. Will always be <=
     *         abs(count).
     */
    public int breakText(String text, boolean measureForwards,
                                float maxWidth, float[] measuredWidth) {
        if (!mHasCompatScaling) {
            return native_breakText(text, measureForwards, maxWidth, measuredWidth);
        }
        final float oldSize = getTextSize();
        setTextSize(oldSize*mCompatScaling);
        int res = native_breakText(text, measureForwards, maxWidth*mCompatScaling,
                measuredWidth);
        setTextSize(oldSize);
        if (measuredWidth != null) measuredWidth[0] *= mInvCompatScaling;
        return res;
    }

    private native int native_breakText(String text, boolean measureForwards,
                                        float maxWidth, float[] measuredWidth);

    /**
     * Return the advance widths for the characters in the string.
     *
     * @param text     The text to measure
     * @param index    The index of the first char to to measure
     * @param count    The number of chars starting with index to measure
     * @param widths   array to receive the advance widths of the characters.
     *                 Must be at least a large as count.
     * @return         the actual number of widths returned.
     */
    public int getTextWidths(char[] text, int index, int count,
                             float[] widths) {
        if ((index | count) < 0 || index + count > text.length
                || count > widths.length) {
            throw new ArrayIndexOutOfBoundsException();
        }
        
        if (!mHasCompatScaling) {
            return native_getTextWidths(mNativePaint, text, index, count, widths);
        }
        final float oldSize = getTextSize();
        setTextSize(oldSize*mCompatScaling);
        int res = native_getTextWidths(mNativePaint, text, index, count, widths);
        setTextSize(oldSize);
        for (int i=0; i<res; i++) {
            widths[i] *= mInvCompatScaling;
        }
        return res;
    }

    /**
     * Return the advance widths for the characters in the string.
     *
     * @param text     The text to measure
     * @param start    The index of the first char to to measure
     * @param end      The end of the text slice to measure
     * @param widths   array to receive the advance widths of the characters.
     *                 Must be at least a large as (end - start).
     * @return         the actual number of widths returned.
     */
    public int getTextWidths(CharSequence text, int start, int end,
                             float[] widths) {
        if (text instanceof String) {
            return getTextWidths((String) text, start, end, widths);
        }
        if (text instanceof SpannedString ||
            text instanceof SpannableString) {
            return getTextWidths(text.toString(), start, end, widths);
        }
        if (text instanceof GraphicsOperations) {
            return ((GraphicsOperations) text).getTextWidths(start, end,
                                                                 widths, this);
        }

        char[] buf = TemporaryBuffer.obtain(end - start);
    	TextUtils.getChars(text, start, end, buf, 0);
    	int result = getTextWidths(buf, 0, end - start, widths);
        TemporaryBuffer.recycle(buf);
    	return result;
    }

    /**
     * Return the advance widths for the characters in the string.
     *
     * @param text   The text to measure
     * @param start  The index of the first char to to measure
     * @param end    The end of the text slice to measure
     * @param widths array to receive the advance widths of the characters.
     *               Must be at least a large as the text.
     * @return       the number of unichars in the specified text.
     */
    public int getTextWidths(String text, int start, int end, float[] widths) {
        if ((start | end | (end - start) | (text.length() - end)) < 0) {
            throw new IndexOutOfBoundsException();
        }
        if (end - start > widths.length) {
            throw new ArrayIndexOutOfBoundsException();
        }
        
        if (!mHasCompatScaling) {
            return native_getTextWidths(mNativePaint, text, start, end, widths);
        }
        final float oldSize = getTextSize();
        setTextSize(oldSize*mCompatScaling);
        int res = native_getTextWidths(mNativePaint, text, start, end, widths);
        setTextSize(oldSize);
        for (int i=0; i<res; i++) {
            widths[i] *= mInvCompatScaling;
        }
        return res;
    }
    
    /**
     * Return the advance widths for the characters in the string.
     *
     * @param text   The text to measure
     * @param widths array to receive the advance widths of the characters.
     *               Must be at least a large as the text.
     * @return       the number of unichars in the specified text.
     */
    public int getTextWidths(String text, float[] widths) {
        return getTextWidths(text, 0, text.length(), widths);
    }

    /**
     * Return the path (outline) for the specified text.
     * Note: just like Canvas.drawText, this will respect the Align setting in
     * the paint.
     *
     * @param text     The text to retrieve the path from
     * @param index    The index of the first character in text
     * @param count    The number of characterss starting with index
     * @param x        The x coordinate of the text's origin
     * @param y        The y coordinate of the text's origin
     * @param path     The path to receive the data describing the text. Must
     *                 be allocated by the caller.
     */
    public void getTextPath(char[] text, int index, int count,
                            float x, float y, Path path) {
        if ((index | count) < 0 || index + count > text.length) {
            throw new ArrayIndexOutOfBoundsException();
        }
        native_getTextPath(mNativePaint, text, index, count, x, y, path.ni());
    }

    /**
     * Return the path (outline) for the specified text.
     * Note: just like Canvas.drawText, this will respect the Align setting
     * in the paint.
     *
     * @param text  The text to retrieve the path from
     * @param start The first character in the text
     * @param end   1 past the last charcter in the text
     * @param x     The x coordinate of the text's origin
     * @param y     The y coordinate of the text's origin
     * @param path  The path to receive the data describing the text. Must
     *              be allocated by the caller.
     */
    public void getTextPath(String text, int start, int end,
                            float x, float y, Path path) {
        if ((start | end | (end - start) | (text.length() - end)) < 0) {
            throw new IndexOutOfBoundsException();
        }
        native_getTextPath(mNativePaint, text, start, end, x, y, path.ni());
    }
    
    /**
     * Return in bounds (allocated by the caller) the smallest rectangle that
     * encloses all of the characters, with an implied origin at (0,0).
     *
     * @param text  String to measure and return its bounds
     * @param start Index of the first char in the string to measure
     * @param end   1 past the last char in the string measure
     * @param bounds Returns the unioned bounds of all the text. Must be
     *               allocated by the caller.
     */
    public void getTextBounds(String text, int start, int end, Rect bounds) {
        if ((start | end | (end - start) | (text.length() - end)) < 0) {
            throw new IndexOutOfBoundsException();
        }
        if (bounds == null) {
            throw new NullPointerException("need bounds Rect");
        }
        nativeGetStringBounds(mNativePaint, text, start, end, bounds);
    }
    
    /**
     * Return in bounds (allocated by the caller) the smallest rectangle that
     * encloses all of the characters, with an implied origin at (0,0).
     *
     * @param text  Array of chars to measure and return their unioned bounds
     * @param index Index of the first char in the array to measure
     * @param count The number of chars, beginning at index, to measure
     * @param bounds Returns the unioned bounds of all the text. Must be
     *               allocated by the caller.
     */
    public void getTextBounds(char[] text, int index, int count, Rect bounds) {
        if ((index | count) < 0 || index + count > text.length) {
            throw new ArrayIndexOutOfBoundsException();
        }
        if (bounds == null) {
            throw new NullPointerException("need bounds Rect");
        }
        nativeGetCharArrayBounds(mNativePaint, text, index, count, bounds);
    }
    
    protected void finalize() throws Throwable {
        finalizer(mNativePaint);
    }

    private static native int native_init();
    private static native int native_initWithPaint(int paint);
    private static native void native_reset(int native_object);
    private static native void native_set(int native_dst, int native_src);
    private static native int native_getStyle(int native_object);
    private static native void native_setStyle(int native_object, int style);
    private static native int native_getStrokeCap(int native_object);
    private static native void native_setStrokeCap(int native_object, int cap);
    private static native int native_getStrokeJoin(int native_object);
    private static native void native_setStrokeJoin(int native_object,
                                                    int join);
    private static native boolean native_getFillPath(int native_object,
                                                     int src, int dst);
    private static native int native_setShader(int native_object, int shader);
    private static native int native_setColorFilter(int native_object,
                                                    int filter);
    private static native int native_setXfermode(int native_object,
                                                 int xfermode);
    private static native int native_setPathEffect(int native_object,
                                                   int effect);
    private static native int native_setMaskFilter(int native_object,
                                                   int maskfilter);
    private static native int native_setTypeface(int native_object,
                                                 int typeface);
    private static native int native_setRasterizer(int native_object,
                                                   int rasterizer);

    private static native int native_getTextAlign(int native_object);
    private static native void native_setTextAlign(int native_object,
                                                   int align);

    private static native float native_getFontMetrics(int native_paint,
                                                      FontMetrics metrics);
    private static native int native_getTextWidths(int native_object,
                            char[] text, int index, int count, float[] widths);
    private static native int native_getTextWidths(int native_object,
                            String text, int start, int end, float[] widths);
    private static native void native_getTextPath(int native_object,
                char[] text, int index, int count, float x, float y, int path);
    private static native void native_getTextPath(int native_object,
                String text, int start, int end, float x, float y, int path);
    private static native void nativeGetStringBounds(int nativePaint,
                                String text, int start, int end, Rect bounds);
    private static native void nativeGetCharArrayBounds(int nativePaint,
                                char[] text, int index, int count, Rect bounds);
    private static native void finalizer(int nativePaint);
}

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