Android example source code file (TypedValue.java)

This example Android source code file (TypedValue.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

complex_unit_fraction, complex_unit_in, complex_unit_mask, complex_unit_mm, complex_unit_sp, dimension_unit_strs, displaymetrics, mantissa_mult, string, type_attribute, type_dimension, type_float, type_string, typedvalue

The TypedValue.java Android example source code

/*
 * Copyright (C) 2007 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.util;

/**
 * Container for a dynamically typed data value.  Primarily used with
 * {@link android.content.res.Resources} for holding resource values.
 */
public class TypedValue {
    /** The value contains no data. */
    public static final int TYPE_NULL = 0x00;

    /** The <var>data field holds a resource identifier. */
    public static final int TYPE_REFERENCE = 0x01;
    /** The <var>data field holds an attribute resource
     *  identifier (referencing an attribute in the current theme
     *  style, not a resource entry). */
    public static final int TYPE_ATTRIBUTE = 0x02;
    /** The <var>string field holds string data.  In addition, if
     *  <var>data is non-zero then it is the string block
     *  index of the string and <var>assetCookie is the set of
     *  assets the string came from. */
    public static final int TYPE_STRING = 0x03;
    /** The <var>data field holds an IEEE 754 floating point number. */
    public static final int TYPE_FLOAT = 0x04;
    /** The <var>data field holds a complex number encoding a
     *  dimension value. */
    public static final int TYPE_DIMENSION = 0x05;
    /** The <var>data field holds a complex number encoding a fraction
     *  of a container. */
    public static final int TYPE_FRACTION = 0x06;

    /** Identifies the start of plain integer values.  Any type value
     *  from this to {@link #TYPE_LAST_INT} means the
     *  <var>data field holds a generic integer value. */
    public static final int TYPE_FIRST_INT = 0x10;

    /** The <var>data field holds a number that was
     *  originally specified in decimal. */
    public static final int TYPE_INT_DEC = 0x10;
    /** The <var>data field holds a number that was
     *  originally specified in hexadecimal (0xn). */
    public static final int TYPE_INT_HEX = 0x11;
    /** The <var>data field holds 0 or 1 that was originally
     *  specified as "false" or "true". */
    public static final int TYPE_INT_BOOLEAN = 0x12;

    /** Identifies the start of integer values that were specified as
     *  color constants (starting with '#'). */
    public static final int TYPE_FIRST_COLOR_INT = 0x1c;

    /** The <var>data field holds a color that was originally
     *  specified as #aarrggbb. */
    public static final int TYPE_INT_COLOR_ARGB8 = 0x1c;
    /** The <var>data field holds a color that was originally
     *  specified as #rrggbb. */
    public static final int TYPE_INT_COLOR_RGB8 = 0x1d;
    /** The <var>data field holds a color that was originally
     *  specified as #argb. */
    public static final int TYPE_INT_COLOR_ARGB4 = 0x1e;
    /** The <var>data field holds a color that was originally
     *  specified as #rgb. */
    public static final int TYPE_INT_COLOR_RGB4 = 0x1f;

    /** Identifies the end of integer values that were specified as color
     *  constants. */
    public static final int TYPE_LAST_COLOR_INT = 0x1f;

    /** Identifies the end of plain integer values. */
    public static final int TYPE_LAST_INT = 0x1f;

    /* ------------------------------------------------------------ */

    /** Complex data: bit location of unit information. */
    public static final int COMPLEX_UNIT_SHIFT = 0;
    /** Complex data: mask to extract unit information (after shifting by
     *  {@link #COMPLEX_UNIT_SHIFT}). This gives us 16 possible types, as
     *  defined below. */
    public static final int COMPLEX_UNIT_MASK = 0xf;

    /** {@link #TYPE_DIMENSION} complex unit: Value is raw pixels. */
    public static final int COMPLEX_UNIT_PX = 0;
    /** {@link #TYPE_DIMENSION} complex unit: Value is Device Independent
     *  Pixels. */
    public static final int COMPLEX_UNIT_DIP = 1;
    /** {@link #TYPE_DIMENSION} complex unit: Value is a scaled pixel. */
    public static final int COMPLEX_UNIT_SP = 2;
    /** {@link #TYPE_DIMENSION} complex unit: Value is in points. */
    public static final int COMPLEX_UNIT_PT = 3;
    /** {@link #TYPE_DIMENSION} complex unit: Value is in inches. */
    public static final int COMPLEX_UNIT_IN = 4;
    /** {@link #TYPE_DIMENSION} complex unit: Value is in millimeters. */
    public static final int COMPLEX_UNIT_MM = 5;

    /** {@link #TYPE_FRACTION} complex unit: A basic fraction of the overall
     *  size. */
    public static final int COMPLEX_UNIT_FRACTION = 0;
    /** {@link #TYPE_FRACTION} complex unit: A fraction of the parent size. */
    public static final int COMPLEX_UNIT_FRACTION_PARENT = 1;

    /** Complex data: where the radix information is, telling where the decimal
     *  place appears in the mantissa. */
    public static final int COMPLEX_RADIX_SHIFT = 4;
    /** Complex data: mask to extract radix information (after shifting by
     * {@link #COMPLEX_RADIX_SHIFT}). This give us 4 possible fixed point 
     * representations as defined below. */ 
    public static final int COMPLEX_RADIX_MASK = 0x3;

    /** Complex data: the mantissa is an integral number -- i.e., 0xnnnnnn.0 */
    public static final int COMPLEX_RADIX_23p0 = 0;
    /** Complex data: the mantissa magnitude is 16 bits -- i.e, 0xnnnn.nn */
    public static final int COMPLEX_RADIX_16p7 = 1;
    /** Complex data: the mantissa magnitude is 8 bits -- i.e, 0xnn.nnnn */
    public static final int COMPLEX_RADIX_8p15 = 2;
    /** Complex data: the mantissa magnitude is 0 bits -- i.e, 0x0.nnnnnn */
    public static final int COMPLEX_RADIX_0p23 = 3;

    /** Complex data: bit location of mantissa information. */
    public static final int COMPLEX_MANTISSA_SHIFT = 8;
    /** Complex data: mask to extract mantissa information (after shifting by
     *  {@link #COMPLEX_MANTISSA_SHIFT}). This gives us 23 bits of precision;
     *  the top bit is the sign. */
    public static final int COMPLEX_MANTISSA_MASK = 0xffffff;

    /* ------------------------------------------------------------ */

    /**
     * If {@link #density} is equal to this value, then the density should be
     * treated as the system's default density value: {@link DisplayMetrics#DENSITY_DEFAULT}.
     */
    public static final int DENSITY_DEFAULT = 0;

    /**
     * If {@link #density} is equal to this value, then there is no density
     * associated with the resource and it should not be scaled.
     */
    public static final int DENSITY_NONE = 0xffff;

    /* ------------------------------------------------------------ */

    /** The type held by this value, as defined by the constants here.
     *  This tells you how to interpret the other fields in the object. */
    public int type;

    /** If the value holds a string, this is it. */
    public CharSequence string;

    /** Basic data in the value, interpreted according to {@link #type} */
    public int data;

    /** Additional information about where the value came from; only
     *  set for strings. */
    public int assetCookie;

    /** If Value came from a resource, this holds the corresponding resource id. */
    public int resourceId;

    /** If Value came from a resource, these are the configurations for which
     *  its contents can change. */
    public int changingConfigurations = -1;

    /**
     * If the Value came from a resource, this holds the corresponding pixel density.
     * */
    public int density;

    /* ------------------------------------------------------------ */

    /** Return the data for this value as a float.  Only use for values
     *  whose type is {@link #TYPE_FLOAT}. */
    public final float getFloat() {
        return Float.intBitsToFloat(data);
    }

    private static final float MANTISSA_MULT =
        1.0f / (1<TypedValue.COMPLEX_RADIX_SHIFT)
                            & TypedValue.COMPLEX_RADIX_MASK];
    }

    /**
     * Converts a complex data value holding a dimension to its final floating 
     * point value. The given <var>data must be structured as a 
     * {@link #TYPE_DIMENSION}.
     *  
     * @param data A complex data value holding a unit, magnitude, and 
     *             mantissa.
     * @param metrics Current display metrics to use in the conversion -- 
     *                supplies display density and scaling information.
     * 
     * @return The complex floating point value multiplied by the appropriate 
     * metrics depending on its unit. 
     */
    public static float complexToDimension(int data, DisplayMetrics metrics)
    {
        return applyDimension(
            (data>>COMPLEX_UNIT_SHIFT)&COMPLEX_UNIT_MASK,
            complexToFloat(data),
            metrics);
    }

    /**
     * Converts a complex data value holding a dimension to its final value
     * as an integer pixel offset.  This is the same as
     * {@link #complexToDimension}, except the raw floating point value is
     * truncated to an integer (pixel) value.
     * The given <var>data must be structured as a 
     * {@link #TYPE_DIMENSION}.
     *  
     * @param data A complex data value holding a unit, magnitude, and 
     *             mantissa.
     * @param metrics Current display metrics to use in the conversion -- 
     *                supplies display density and scaling information.
     * 
     * @return The number of pixels specified by the data and its desired
     * multiplier and units.
     */
    public static int complexToDimensionPixelOffset(int data,
            DisplayMetrics metrics)
    {
        return (int)applyDimension(
                (data>>COMPLEX_UNIT_SHIFT)&COMPLEX_UNIT_MASK,
                complexToFloat(data),
                metrics);
    }

    /**
     * Converts a complex data value holding a dimension to its final value
     * as an integer pixel size.  This is the same as
     * {@link #complexToDimension}, except the raw floating point value is
     * converted to an integer (pixel) value for use as a size.  A size
     * conversion involves rounding the base value, and ensuring that a
     * non-zero base value is at least one pixel in size.
     * The given <var>data must be structured as a 
     * {@link #TYPE_DIMENSION}.
     *  
     * @param data A complex data value holding a unit, magnitude, and 
     *             mantissa.
     * @param metrics Current display metrics to use in the conversion -- 
     *                supplies display density and scaling information.
     * 
     * @return The number of pixels specified by the data and its desired
     * multiplier and units.
     */
    public static int complexToDimensionPixelSize(int data,
            DisplayMetrics metrics)
    {
        final float value = complexToFloat(data);
        final float f = applyDimension(
                (data>>COMPLEX_UNIT_SHIFT)&COMPLEX_UNIT_MASK,
                value,
                metrics);
        final int res = (int)(f+0.5f);
        if (res != 0) return res;
        if (value == 0) return 0;
        if (value > 0) return 1;
        return -1;
    }

    public static float complexToDimensionNoisy(int data, DisplayMetrics metrics)
    {
        float res = complexToDimension(data, metrics);
        System.out.println(
            "Dimension (0x" + ((data>>TypedValue.COMPLEX_MANTISSA_SHIFT)
                               & TypedValue.COMPLEX_MANTISSA_MASK)
            + "*" + (RADIX_MULTS[(data>>TypedValue.COMPLEX_RADIX_SHIFT)
                                & TypedValue.COMPLEX_RADIX_MASK] / MANTISSA_MULT)
            + ")" + DIMENSION_UNIT_STRS[(data>>COMPLEX_UNIT_SHIFT)
                                & COMPLEX_UNIT_MASK]
            + " = " + res);
        return res;
    }

    /**
     * Converts an unpacked complex data value holding a dimension to its final floating 
     * point value. The two parameters <var>unit and value
     * are as in {@link #TYPE_DIMENSION}.
     *  
     * @param unit The unit to convert from.
     * @param value The value to apply the unit to.
     * @param metrics Current display metrics to use in the conversion -- 
     *                supplies display density and scaling information.
     * 
     * @return The complex floating point value multiplied by the appropriate 
     * metrics depending on its unit. 
     */
    public static float applyDimension(int unit, float value,
                                       DisplayMetrics metrics)
    {
        switch (unit) {
        case COMPLEX_UNIT_PX:
            return value;
        case COMPLEX_UNIT_DIP:
            return value * metrics.density;
        case COMPLEX_UNIT_SP:
            return value * metrics.scaledDensity;
        case COMPLEX_UNIT_PT:
            return value * metrics.xdpi * (1.0f/72);
        case COMPLEX_UNIT_IN:
            return value * metrics.xdpi;
        case COMPLEX_UNIT_MM:
            return value * metrics.xdpi * (1.0f/25.4f);
        }
        return 0;
    }

    /**
     * Return the data for this value as a dimension.  Only use for values 
     * whose type is {@link #TYPE_DIMENSION}. 
     * 
     * @param metrics Current display metrics to use in the conversion -- 
     *                supplies display density and scaling information.
     * 
     * @return The complex floating point value multiplied by the appropriate 
     * metrics depending on its unit. 
     */
    public float getDimension(DisplayMetrics metrics)
    {
        return complexToDimension(data, metrics);
    }

    /**
     * Converts a complex data value holding a fraction to its final floating 
     * point value. The given <var>data must be structured as a 
     * {@link #TYPE_FRACTION}.
     * 
     * @param data A complex data value holding a unit, magnitude, and 
     *             mantissa.
     * @param base The base value of this fraction.  In other words, a 
     *             standard fraction is multiplied by this value.
     * @param pbase The parent base value of this fraction.  In other 
     *             words, a parent fraction (nn%p) is multiplied by this
     *             value.
     * 
     * @return The complex floating point value multiplied by the appropriate 
     * base value depending on its unit. 
     */
    public static float complexToFraction(int data, float base, float pbase)
    {
        switch ((data>>COMPLEX_UNIT_SHIFT)&COMPLEX_UNIT_MASK) {
        case COMPLEX_UNIT_FRACTION:
            return complexToFloat(data) * base;
        case COMPLEX_UNIT_FRACTION_PARENT:
            return complexToFloat(data) * pbase;
        }
        return 0;
    }

    /**
     * Return the data for this value as a fraction.  Only use for values whose 
     * type is {@link #TYPE_FRACTION}. 
     * 
     * @param base The base value of this fraction.  In other words, a 
     *             standard fraction is multiplied by this value.
     * @param pbase The parent base value of this fraction.  In other 
     *             words, a parent fraction (nn%p) is multiplied by this
     *             value.
     * 
     * @return The complex floating point value multiplied by the appropriate 
     * base value depending on its unit. 
     */
    public float getFraction(float base, float pbase)
    {
        return complexToFraction(data, base, pbase);
    }

    /**
     * Regardless of the actual type of the value, try to convert it to a
     * string value.  For example, a color type will be converted to a
     * string of the form #aarrggbb.
     * 
     * @return CharSequence The coerced string value.  If the value is
     *         null or the type is not known, null is returned.
     */
    public final CharSequence coerceToString()
    {
        int t = type;
        if (t == TYPE_STRING) {
            return string;
        }
        return coerceToString(t, data);
    }

    private static final String[] DIMENSION_UNIT_STRS = new String[] {
        "px", "dip", "sp", "pt", "in", "mm"
    };
    private static final String[] FRACTION_UNIT_STRS = new String[] {
        "%", "%p"
    };

    /**
     * Perform type conversion as per {@link #coerceToString()} on an
     * explicitly supplied type and data.
     * 
     * @param type The data type identifier.
     * @param data The data value.
     * 
     * @return String The coerced string value.  If the value is
     *         null or the type is not known, null is returned.
     */
    public static final String coerceToString(int type, int data)
    {
        switch (type) {
        case TYPE_NULL:
            return null;
        case TYPE_REFERENCE:
            return "@" + data;
        case TYPE_ATTRIBUTE:
            return "?" + data;
        case TYPE_FLOAT:
            return Float.toString(Float.intBitsToFloat(data));
        case TYPE_DIMENSION:
            return Float.toString(complexToFloat(data)) + DIMENSION_UNIT_STRS[
                (data>>COMPLEX_UNIT_SHIFT)&COMPLEX_UNIT_MASK];
        case TYPE_FRACTION:
            return Float.toString(complexToFloat(data)*100) + FRACTION_UNIT_STRS[
                (data>>COMPLEX_UNIT_SHIFT)&COMPLEX_UNIT_MASK];
        case TYPE_INT_HEX:
            return "0x" + Integer.toHexString(data);
        case TYPE_INT_BOOLEAN:
            return data != 0 ? "true" : "false";
        }

        if (type >= TYPE_FIRST_COLOR_INT && type <= TYPE_LAST_COLOR_INT) {
            return "#" + Integer.toHexString(data);
        } else if (type >= TYPE_FIRST_INT && type <= TYPE_LAST_INT) {
            return Integer.toString(data);
        }

        return null;
    }

    public void setTo(TypedValue other)
    {
        type = other.type;
        string = other.string;
        data = other.data;
        assetCookie = other.assetCookie;
        resourceId = other.resourceId;
        density = other.density;
    }

    public String toString()
    {
        StringBuilder sb = new StringBuilder();
        sb.append("TypedValue{t=0x").append(Integer.toHexString(type));
        sb.append("/d=0x").append(Integer.toHexString(data));
        if (type == TYPE_STRING) {
            sb.append(" \"").append(string != null ? string : "<null>").append("\"");
        }
        if (assetCookie != 0) {
            sb.append(" a=").append(assetCookie);
        }
        if (resourceId != 0) {
            sb.append(" r=0x").append(Integer.toHexString(resourceId));
        }
        sb.append("}");
        return sb.toString();
    }
};