Android example source code file (Window.java)

This example Android source code file (Window.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

android, callback, content, context, default_features, display, drawable, drawing, feature_context_menu, feature_options_panel, keyevent, localwindowmanager, menu, os, paint, string, ui, view, window, windowmanager

The Window.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.view;

import android.content.Context;
import android.content.res.Configuration;
import android.content.res.TypedArray;
import android.graphics.PixelFormat;
import android.graphics.drawable.Drawable;
import android.net.Uri;
import android.os.Bundle;
import android.os.IBinder;
import android.view.accessibility.AccessibilityEvent;

/**
 * Abstract base class for a top-level window look and behavior policy.  An
 * instance of this class should be used as the top-level view added to the
 * window manager. It provides standard UI policies such as a background, title
 * area, default key processing, etc.
 *
 * <p>The only existing implementation of this abstract class is
 * android.policy.PhoneWindow, which you should instantiate when needing a
 * Window.  Eventually that class will be refactored and a factory method
 * added for creating Window instances without knowing about a particular
 * implementation.
 */
public abstract class Window {
    /** Flag for the "options panel" feature.  This is enabled by default. */
    public static final int FEATURE_OPTIONS_PANEL = 0;
    /** Flag for the "no title" feature, turning off the title at the top
     *  of the screen. */
    public static final int FEATURE_NO_TITLE = 1;
    /** Flag for the progress indicator feature */
    public static final int FEATURE_PROGRESS = 2;
    /** Flag for having an icon on the left side of the title bar */
    public static final int FEATURE_LEFT_ICON = 3;
    /** Flag for having an icon on the right side of the title bar */
    public static final int FEATURE_RIGHT_ICON = 4;
    /** Flag for indeterminate progress */
    public static final int FEATURE_INDETERMINATE_PROGRESS = 5;
    /** Flag for the context menu.  This is enabled by default. */
    public static final int FEATURE_CONTEXT_MENU = 6;
    /** Flag for custom title. You cannot combine this feature with other title features. */
    public static final int FEATURE_CUSTOM_TITLE = 7;
    /** Flag for asking for an OpenGL enabled window.
        All 2D graphics will be handled by OpenGL ES.
        @hide
    */
    public static final int FEATURE_OPENGL = 8;
    /** Flag for setting the progress bar's visibility to VISIBLE */
    public static final int PROGRESS_VISIBILITY_ON = -1;
    /** Flag for setting the progress bar's visibility to GONE */
    public static final int PROGRESS_VISIBILITY_OFF = -2;
    /** Flag for setting the progress bar's indeterminate mode on */
    public static final int PROGRESS_INDETERMINATE_ON = -3;
    /** Flag for setting the progress bar's indeterminate mode off */
    public static final int PROGRESS_INDETERMINATE_OFF = -4;
    /** Starting value for the (primary) progress */
    public static final int PROGRESS_START = 0;
    /** Ending value for the (primary) progress */
    public static final int PROGRESS_END = 10000;
    /** Lowest possible value for the secondary progress */
    public static final int PROGRESS_SECONDARY_START = 20000;
    /** Highest possible value for the secondary progress */
    public static final int PROGRESS_SECONDARY_END = 30000;
    
    /** The default features enabled */
    @SuppressWarnings({"PointlessBitwiseExpression"})
    protected static final int DEFAULT_FEATURES = (1 << FEATURE_OPTIONS_PANEL) |
            (1 << FEATURE_CONTEXT_MENU);

    /**
     * The ID that the main layout in the XML layout file should have.
     */
    public static final int ID_ANDROID_CONTENT = com.android.internal.R.id.content;

    private final Context mContext;
    
    private TypedArray mWindowStyle;
    private Callback mCallback;
    private WindowManager mWindowManager;
    private IBinder mAppToken;
    private String mAppName;
    private Window mContainer;
    private Window mActiveChild;
    private boolean mIsActive = false;
    private boolean mHasChildren = false;
    private int mForcedWindowFlags = 0;

    private int mFeatures = DEFAULT_FEATURES;
    private int mLocalFeatures = DEFAULT_FEATURES;

    private boolean mHaveWindowFormat = false;
    private int mDefaultWindowFormat = PixelFormat.OPAQUE;

    private boolean mHasSoftInputMode = false;
    
    // The current window attributes.
    private final WindowManager.LayoutParams mWindowAttributes =
        new WindowManager.LayoutParams();

    /**
     * API from a Window back to its caller.  This allows the client to
     * intercept key dispatching, panels and menus, etc.
     */
    public interface Callback {
        /**
         * Called to process key events.  At the very least your
         * implementation must call
         * {@link android.view.Window#superDispatchKeyEvent} to do the
         * standard key processing.
         *
         * @param event The key event.
         *
         * @return boolean Return true if this event was consumed.
         */
        public boolean dispatchKeyEvent(KeyEvent event);

        /**
         * Called to process touch screen events.  At the very least your
         * implementation must call
         * {@link android.view.Window#superDispatchTouchEvent} to do the
         * standard touch screen processing.
         *
         * @param event The touch screen event.
         *
         * @return boolean Return true if this event was consumed.
         */
        public boolean dispatchTouchEvent(MotionEvent event);
        
        /**
         * Called to process trackball events.  At the very least your
         * implementation must call
         * {@link android.view.Window#superDispatchTrackballEvent} to do the
         * standard trackball processing.
         *
         * @param event The trackball event.
         *
         * @return boolean Return true if this event was consumed.
         */
        public boolean dispatchTrackballEvent(MotionEvent event);

        /**
         * Called to process population of {@link AccessibilityEvent}s.
         *
         * @param event The event.
         *
         * @return boolean Return true if event population was completed.
         */
        public boolean dispatchPopulateAccessibilityEvent(AccessibilityEvent event);

        /**
         * Instantiate the view to display in the panel for 'featureId'.
         * You can return null, in which case the default content (typically
         * a menu) will be created for you.
         *
         * @param featureId Which panel is being created.
         *
         * @return view The top-level view to place in the panel.
         *
         * @see #onPreparePanel
         */
        public View onCreatePanelView(int featureId);

        /**
         * Initialize the contents of the menu for panel 'featureId'.  This is
         * called if onCreatePanelView() returns null, giving you a standard
         * menu in which you can place your items.  It is only called once for
         * the panel, the first time it is shown.
         *
         * <p>You can safely hold on to menu (and any items created
         * from it), making modifications to it as desired, until the next
         * time onCreatePanelMenu() is called for this feature.
         *
         * @param featureId The panel being created.
         * @param menu The menu inside the panel.
         *
         * @return boolean You must return true for the panel to be displayed;
         *         if you return false it will not be shown.
         */
        public boolean onCreatePanelMenu(int featureId, Menu menu);

        /**
         * Prepare a panel to be displayed.  This is called right before the
         * panel window is shown, every time it is shown.
         *
         * @param featureId The panel that is being displayed.
         * @param view The View that was returned by onCreatePanelView().
         * @param menu If onCreatePanelView() returned null, this is the Menu
         *             being displayed in the panel.
         *
         * @return boolean You must return true for the panel to be displayed;
         *         if you return false it will not be shown.
         *
         * @see #onCreatePanelView
         */
        public boolean onPreparePanel(int featureId, View view, Menu menu);

        /**
         * Called when a panel's menu is opened by the user. This may also be
         * called when the menu is changing from one type to another (for
         * example, from the icon menu to the expanded menu).
         * 
         * @param featureId The panel that the menu is in.
         * @param menu The menu that is opened.
         * @return Return true to allow the menu to open, or false to prevent
         *         the menu from opening.
         */
        public boolean onMenuOpened(int featureId, Menu menu);
        
        /**
         * Called when a panel's menu item has been selected by the user.
         *
         * @param featureId The panel that the menu is in.
         * @param item The menu item that was selected.
         *
         * @return boolean Return true to finish processing of selection, or
         *         false to perform the normal menu handling (calling its
         *         Runnable or sending a Message to its target Handler).
         */
        public boolean onMenuItemSelected(int featureId, MenuItem item);

        /**
         * This is called whenever the current window attributes change.
         *
         */
        public void onWindowAttributesChanged(WindowManager.LayoutParams attrs);

        /**
         * This hook is called whenever the content view of the screen changes
         * (due to a call to
         * {@link Window#setContentView(View, android.view.ViewGroup.LayoutParams)
         * Window.setContentView} or
         * {@link Window#addContentView(View, android.view.ViewGroup.LayoutParams)
         * Window.addContentView}).
         */
        public void onContentChanged();

        /**
         * This hook is called whenever the window focus changes.  See
         * {@link View#onWindowFocusChanged(boolean)
         * View.onWindowFocusChanged(boolean)} for more information.
         *
         * @param hasFocus Whether the window now has focus.
         */
        public void onWindowFocusChanged(boolean hasFocus);

        /**
         * Called when the window has been attached to the window manager.
         * See {@link View#onAttachedToWindow() View.onAttachedToWindow()}
         * for more information.
         */
        public void onAttachedToWindow();
        
        /**
         * Called when the window has been attached to the window manager.
         * See {@link View#onDetachedFromWindow() View.onDetachedFromWindow()}
         * for more information.
         */
        public void onDetachedFromWindow();
        
        /**
         * Called when a panel is being closed.  If another logical subsequent
         * panel is being opened (and this panel is being closed to make room for the subsequent
         * panel), this method will NOT be called.
         * 
         * @param featureId The panel that is being displayed.
         * @param menu If onCreatePanelView() returned null, this is the Menu
         *            being displayed in the panel.
         */
        public void onPanelClosed(int featureId, Menu menu);
        
        /**
         * Called when the user signals the desire to start a search.
         * 
         * @return true if search launched, false if activity refuses (blocks)
         * 
         * @see android.app.Activity#onSearchRequested() 
         */
        public boolean onSearchRequested();
    }

    public Window(Context context) {
        mContext = context;
    }

    /**
     * Return the Context this window policy is running in, for retrieving
     * resources and other information.
     *
     * @return Context The Context that was supplied to the constructor.
     */
    public final Context getContext() {
        return mContext;
    }

    /**
     * Return the {@link android.R.styleable#Window} attributes from this
     * window's theme.
     */
    public final TypedArray getWindowStyle() {
        synchronized (this) {
            if (mWindowStyle == null) {
                mWindowStyle = mContext.obtainStyledAttributes(
                        com.android.internal.R.styleable.Window);
            }
            return mWindowStyle;
        }
    }
    
    /**
     * Set the container for this window.  If not set, the DecorWindow
     * operates as a top-level window; otherwise, it negotiates with the
     * container to display itself appropriately.
     *
     * @param container The desired containing Window.
     */
    public void setContainer(Window container) {
        mContainer = container;
        if (container != null) {
            // Embedded screens never have a title.
            mFeatures |= 1< used for displaying the
     * Window itself -- that must be done by the client.
     *
     * @param wm The ViewManager for adding new windows.
     */
    public void setWindowManager(WindowManager wm,
            IBinder appToken, String appName) {
        mAppToken = appToken;
        mAppName = appName;
        if (wm == null) {
            wm = WindowManagerImpl.getDefault();
        }
        mWindowManager = new LocalWindowManager(wm);
    }

    private class LocalWindowManager implements WindowManager {
        LocalWindowManager(WindowManager wm) {
            mWindowManager = wm;
            mDefaultDisplay = mContext.getResources().getDefaultDisplay(
                    mWindowManager.getDefaultDisplay());
        }

        public final void addView(View view, ViewGroup.LayoutParams params) {
            // Let this throw an exception on a bad params.
            WindowManager.LayoutParams wp = (WindowManager.LayoutParams)params;
            CharSequence curTitle = wp.getTitle();
            if (wp.type >= WindowManager.LayoutParams.FIRST_SUB_WINDOW &&
                wp.type <= WindowManager.LayoutParams.LAST_SUB_WINDOW) {
                if (wp.token == null) {
                    View decor = peekDecorView();
                    if (decor != null) {
                        wp.token = decor.getWindowToken();
                    }
                }
                if (curTitle == null || curTitle.length() == 0) {
                    String title;
                    if (wp.type == WindowManager.LayoutParams.TYPE_APPLICATION_MEDIA) {
                        title="Media";
                    } else if (wp.type == WindowManager.LayoutParams.TYPE_APPLICATION_MEDIA_OVERLAY) {
                        title="MediaOvr";
                    } else if (wp.type == WindowManager.LayoutParams.TYPE_APPLICATION_PANEL) {
                        title="Panel";
                    } else if (wp.type == WindowManager.LayoutParams.TYPE_APPLICATION_SUB_PANEL) {
                        title="SubPanel";
                    } else if (wp.type == WindowManager.LayoutParams.TYPE_APPLICATION_ATTACHED_DIALOG) {
                        title="AtchDlg";
                    } else {
                        title=Integer.toString(wp.type);
                    }
                    if (mAppName != null) {
                        title += ":" + mAppName;
                    }
                    wp.setTitle(title);
                }
            } else {
                if (wp.token == null) {
                    wp.token = mContainer == null ? mAppToken : mContainer.mAppToken;
                }
                if ((curTitle == null || curTitle.length() == 0)
                        && mAppName != null) {
                    wp.setTitle(mAppName);
                }
           }
            if (wp.packageName == null) {
                wp.packageName = mContext.getPackageName();
            }
            mWindowManager.addView(view, params);
        }

        public void updateViewLayout(View view, ViewGroup.LayoutParams params) {
            mWindowManager.updateViewLayout(view, params);
        }

        public final void removeView(View view) {
            mWindowManager.removeView(view);
        }

        public final void removeViewImmediate(View view) {
            mWindowManager.removeViewImmediate(view);
        }

        public Display getDefaultDisplay() {
            return mDefaultDisplay;
        }
        
        private final WindowManager mWindowManager;

        private final Display mDefaultDisplay;
    }

    /**
     * Return the window manager allowing this Window to display its own
     * windows.
     *
     * @return WindowManager The ViewManager.
     */
    public WindowManager getWindowManager() {
        return mWindowManager;
    }

    /**
     * Set the Callback interface for this window, used to intercept key
     * events and other dynamic operations in the window.
     *
     * @param callback The desired Callback interface.
     */
    public void setCallback(Callback callback) {
        mCallback = callback;
    }

    /**
     * Return the current Callback interface for this window.
     */
    public final Callback getCallback() {
        return mCallback;
    }

    /**
     * Return whether this window is being displayed with a floating style
     * (based on the {@link android.R.attr#windowIsFloating} attribute in
     * the style/theme).
     *
     * @return Returns true if the window is configured to be displayed floating
     * on top of whatever is behind it.
     */
    public abstract boolean isFloating();

    /**
     * Set the width and height layout parameters of the window.  The default
     * for both of these is MATCH_PARENT; you can change them to WRAP_CONTENT to
     * make a window that is not full-screen.
     *
     * @param width The desired layout width of the window.
     * @param height The desired layout height of the window.
     */
    public void setLayout(int width, int height)
    {
        final WindowManager.LayoutParams attrs = getAttributes();
        attrs.width = width;
        attrs.height = height;
        if (mCallback != null) {
            mCallback.onWindowAttributesChanged(attrs);
        }
    }

    /**
     * Set the gravity of the window, as per the Gravity constants.  This
     * controls how the window manager is positioned in the overall window; it
     * is only useful when using WRAP_CONTENT for the layout width or height.
     *
     * @param gravity The desired gravity constant.
     *
     * @see Gravity
     * @see #setLayout
     */
    public void setGravity(int gravity)
    {
        final WindowManager.LayoutParams attrs = getAttributes();
        attrs.gravity = gravity;
        if (mCallback != null) {
            mCallback.onWindowAttributesChanged(attrs);
        }
    }

    /**
     * Set the type of the window, as per the WindowManager.LayoutParams
     * types.
     *
     * @param type The new window type (see WindowManager.LayoutParams).
     */
    public void setType(int type) {
        final WindowManager.LayoutParams attrs = getAttributes();
        attrs.type = type;
        if (mCallback != null) {
            mCallback.onWindowAttributesChanged(attrs);
        }
    }

    /**
     * Set the format of window, as per the PixelFormat types.  This overrides
     * the default format that is selected by the Window based on its
     * window decorations.
     *
     * @param format The new window format (see PixelFormat).  Use
     *               PixelFormat.UNKNOWN to allow the Window to select
     *               the format.
     *
     * @see PixelFormat
     */
    public void setFormat(int format) {
        final WindowManager.LayoutParams attrs = getAttributes();
        if (format != PixelFormat.UNKNOWN) {
            attrs.format = format;
            mHaveWindowFormat = true;
        } else {
            attrs.format = mDefaultWindowFormat;
            mHaveWindowFormat = false;
        }
        if (mCallback != null) {
            mCallback.onWindowAttributesChanged(attrs);
        }
    }

    /**
     * Specify custom animations to use for the window, as per
     * {@link WindowManager.LayoutParams#windowAnimations
     * WindowManager.LayoutParams.windowAnimations}.  Providing anything besides
     * 0 here will override the animations the window would
     * normally retrieve from its theme.
     */
    public void setWindowAnimations(int resId) {
        final WindowManager.LayoutParams attrs = getAttributes();
        attrs.windowAnimations = resId;
        if (mCallback != null) {
            mCallback.onWindowAttributesChanged(attrs);
        }
    }

    /**
     * Specify an explicit soft input mode to use for the window, as per
     * {@link WindowManager.LayoutParams#softInputMode
     * WindowManager.LayoutParams.softInputMode}.  Providing anything besides
     * "unspecified" here will override the input mode the window would
     * normally retrieve from its theme.
     */
    public void setSoftInputMode(int mode) {
        final WindowManager.LayoutParams attrs = getAttributes();
        if (mode != WindowManager.LayoutParams.SOFT_INPUT_STATE_UNSPECIFIED) {
            attrs.softInputMode = mode;
            mHasSoftInputMode = true;
        } else {
            mHasSoftInputMode = false;
        }
        if (mCallback != null) {
            mCallback.onWindowAttributesChanged(attrs);
        }
    }
    
    /**
     * Convenience function to set the flag bits as specified in flags, as
     * per {@link #setFlags}.
     * @param flags The flag bits to be set.
     * @see #setFlags
     */
    public void addFlags(int flags) {
        setFlags(flags, flags);
    }
    
    /**
     * Convenience function to clear the flag bits as specified in flags, as
     * per {@link #setFlags}.
     * @param flags The flag bits to be cleared.
     * @see #setFlags
     */
    public void clearFlags(int flags) {
        setFlags(0, flags);
    }

    /**
     * Set the flags of the window, as per the
     * {@link WindowManager.LayoutParams WindowManager.LayoutParams}
     * flags.
     * 
     * <p>Note that some flags must be set before the window decoration is
     * created (by the first call to
     * {@link #setContentView(View, android.view.ViewGroup.LayoutParams)} or
     * {@link #getDecorView()}:
     * {@link WindowManager.LayoutParams#FLAG_LAYOUT_IN_SCREEN} and
     * {@link WindowManager.LayoutParams#FLAG_LAYOUT_INSET_DECOR}.  These
     * will be set for you based on the {@link android.R.attr#windowIsFloating}
     * attribute.
     *
     * @param flags The new window flags (see WindowManager.LayoutParams).
     * @param mask Which of the window flag bits to modify.
     */
    public void setFlags(int flags, int mask) {
        final WindowManager.LayoutParams attrs = getAttributes();
        attrs.flags = (attrs.flags&~mask) | (flags&mask);
        mForcedWindowFlags |= mask;
        if (mCallback != null) {
            mCallback.onWindowAttributesChanged(attrs);
        }
    }

    /**
     * Specify custom window attributes.  <strong>PLEASE NOTE: the
     * layout params you give here should generally be from values previously
     * retrieved with {@link #getAttributes()}; you probably do not want to
     * blindly create and apply your own, since this will blow away any values
     * set by the framework that you are not interested in.
     *
     * @param a The new window attributes, which will completely override any
     *          current values.
     */
    public void setAttributes(WindowManager.LayoutParams a) {
        mWindowAttributes.copyFrom(a);
        if (mCallback != null) {
            mCallback.onWindowAttributesChanged(mWindowAttributes);
        }
    }

    /**
     * Retrieve the current window attributes associated with this panel.
     *
     * @return WindowManager.LayoutParams Either the existing window
     *         attributes object, or a freshly created one if there is none.
     */
    public final WindowManager.LayoutParams getAttributes() {
        return mWindowAttributes;
    }

    /**
     * Return the window flags that have been explicitly set by the client,
     * so will not be modified by {@link #getDecorView}.
     */
    protected final int getForcedWindowFlags() {
        return mForcedWindowFlags;
    }
    
    /**
     * Has the app specified their own soft input mode?
     */
    protected final boolean hasSoftInputMode() {
        return mHasSoftInputMode;
    }
    
    /**
     * Enable extended screen features.  This must be called before
     * setContentView().  May be called as many times as desired as long as it
     * is before setContentView().  If not called, no extended features
     * will be available.  You can not turn off a feature once it is requested.
     * You canot use other title features with {@link #FEATURE_CUSTOM_TITLE}.
     *
     * @param featureId The desired features, defined as constants by Window.
     * @return The features that are now set.
     */
    public boolean requestFeature(int featureId) {
        final int flag = 1<Note that calling this function for the first time "locks in"
     * various window characteristics as described in
     * {@link #setContentView(View, android.view.ViewGroup.LayoutParams)}.</em>

     * 
     * @return Returns the top-level window decor view.
     */
    public abstract View getDecorView();

    /**
     * Retrieve the current decor view, but only if it has already been created;
     * otherwise returns null.
     * 
     * @return Returns the top-level window decor or null.
     * @see #getDecorView
     */
    public abstract View peekDecorView();

    public abstract Bundle saveHierarchyState();
    
    public abstract void restoreHierarchyState(Bundle savedInstanceState);
    
    protected abstract void onActive();

    /**
     * Return the feature bits that are enabled.  This is the set of features
     * that were given to requestFeature(), and are being handled by this
     * Window itself or its container.  That is, it is the set of
     * requested features that you can actually use.
     *
     * <p>To do: add a public version of this API that allows you to check for
     * features by their feature ID.
     *
     * @return int The feature bits.
     */
    protected final int getFeatures()
    {
        return mFeatures;
    }

    /**
     * Return the feature bits that are being implemented by this Window.
     * This is the set of features that were given to requestFeature(), and are
     * being handled by only this Window itself, not by its containers.
     *
     * @return int The feature bits.
     */
    protected final int getLocalFeatures()
    {
        return mLocalFeatures;
    }

    /**
     * Set the default format of window, as per the PixelFormat types.  This
     * is the format that will be used unless the client specifies in explicit
     * format with setFormat();
     *
     * @param format The new window format (see PixelFormat).
     *
     * @see #setFormat
     * @see PixelFormat
     */
    protected void setDefaultWindowFormat(int format) {
        mDefaultWindowFormat = format;
        if (!mHaveWindowFormat) {
            final WindowManager.LayoutParams attrs = getAttributes();
            attrs.format = format;
            if (mCallback != null) {
                mCallback.onWindowAttributesChanged(attrs);
            }
        }
    }

    public abstract void setChildDrawable(int featureId, Drawable drawable);

    public abstract void setChildInt(int featureId, int value);

    /**
     * Is a keypress one of the defined shortcut keys for this window.
     * @param keyCode the key code from {@link android.view.KeyEvent} to check.
     * @param event the {@link android.view.KeyEvent} to use to help check.
     */
    public abstract boolean isShortcutKey(int keyCode, KeyEvent event);
    
    /**
     * @see android.app.Activity#setVolumeControlStream(int) 
     */
    public abstract void setVolumeControlStream(int streamType);

    /**
     * @see android.app.Activity#getVolumeControlStream()
     */
    public abstract int getVolumeControlStream();
    
}