| /* |
| * 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.annotation.IntRange; |
| import android.annotation.NonNull; |
| import android.graphics.Canvas; |
| import android.graphics.PixelFormat; |
| import android.graphics.Rect; |
| |
| /** |
| * Abstract interface to someone holding a display surface. Allows you to |
| * control the surface size and format, edit the pixels in the surface, and |
| * monitor changes to the surface. This interface is typically available |
| * through the {@link SurfaceView} class. |
| * |
| * <p>When using this interface from a thread other than the one running |
| * its {@link SurfaceView}, you will want to carefully read the |
| * methods |
| * {@link #lockCanvas} and {@link Callback#surfaceCreated Callback.surfaceCreated()}. |
| */ |
| public interface SurfaceHolder { |
| |
| /** @deprecated this is ignored, this value is set automatically when needed. */ |
| @Deprecated |
| public static final int SURFACE_TYPE_NORMAL = 0; |
| /** @deprecated this is ignored, this value is set automatically when needed. */ |
| @Deprecated |
| public static final int SURFACE_TYPE_HARDWARE = 1; |
| /** @deprecated this is ignored, this value is set automatically when needed. */ |
| @Deprecated |
| public static final int SURFACE_TYPE_GPU = 2; |
| /** @deprecated this is ignored, this value is set automatically when needed. */ |
| @Deprecated |
| public static final int SURFACE_TYPE_PUSH_BUFFERS = 3; |
| |
| /** |
| * Exception that is thrown from {@link #lockCanvas} when called on a Surface |
| * whose type is SURFACE_TYPE_PUSH_BUFFERS. |
| */ |
| public static class BadSurfaceTypeException extends RuntimeException { |
| public BadSurfaceTypeException() { |
| } |
| |
| public BadSurfaceTypeException(String name) { |
| super(name); |
| } |
| } |
| |
| /** |
| * A client may implement this interface to receive information about |
| * changes to the surface. When used with a {@link SurfaceView}, the |
| * Surface being held is only available between calls to |
| * {@link #surfaceCreated(SurfaceHolder)} and |
| * {@link #surfaceDestroyed(SurfaceHolder)}. The Callback is set with |
| * {@link SurfaceHolder#addCallback SurfaceHolder.addCallback} method. |
| */ |
| public interface Callback { |
| /** |
| * This is called immediately after the surface is first created. |
| * Implementations of this should start up whatever rendering code |
| * they desire. Note that only one thread can ever draw into |
| * a {@link Surface}, so you should not draw into the Surface here |
| * if your normal rendering will be in another thread. |
| * |
| * @param holder The SurfaceHolder whose surface is being created. |
| */ |
| void surfaceCreated(@NonNull SurfaceHolder holder); |
| |
| /** |
| * This is called immediately after any structural changes (format or |
| * size) have been made to the surface. You should at this point update |
| * the imagery in the surface. This method is always called at least |
| * once, after {@link #surfaceCreated}. |
| * |
| * @param holder The SurfaceHolder whose surface has changed. |
| * @param format The new {@link PixelFormat} of the surface. |
| * @param width The new width of the surface. |
| * @param height The new height of the surface. |
| */ |
| void surfaceChanged(@NonNull SurfaceHolder holder, @PixelFormat.Format int format, |
| @IntRange(from = 0) int width, @IntRange(from = 0) int height); |
| |
| /** |
| * This is called immediately before a surface is being destroyed. After |
| * returning from this call, you should no longer try to access this |
| * surface. If you have a rendering thread that directly accesses |
| * the surface, you must ensure that thread is no longer touching the |
| * Surface before returning from this function. |
| * |
| * @param holder The SurfaceHolder whose surface is being destroyed. |
| */ |
| void surfaceDestroyed(@NonNull SurfaceHolder holder); |
| } |
| |
| /** |
| * Additional callbacks that can be received for {@link Callback}. |
| */ |
| public interface Callback2 extends Callback { |
| /** |
| * Called when the application needs to redraw the content of its |
| * surface, after it is resized or for some other reason. By not |
| * returning from here until the redraw is complete, you can ensure that |
| * the user will not see your surface in a bad state (at its new |
| * size before it has been correctly drawn that way). This will |
| * typically be preceeded by a call to {@link #surfaceChanged}. |
| * |
| * As of O, {@link #surfaceRedrawNeededAsync} may be implemented |
| * to provide a non-blocking implementation. If {@link #surfaceRedrawNeededAsync} |
| * is not implemented, then this will be called instead. |
| * |
| * @param holder The SurfaceHolder whose surface has changed. |
| */ |
| void surfaceRedrawNeeded(@NonNull SurfaceHolder holder); |
| |
| /** |
| * An alternative to surfaceRedrawNeeded where it is not required to block |
| * until the redraw is complete. You should initiate the redraw, and return, |
| * later invoking drawingFinished when your redraw is complete. |
| * |
| * This can be useful to avoid blocking your main application thread on rendering. |
| * |
| * As of O, if this is implemented {@link #surfaceRedrawNeeded} will not be called. |
| * However it is still recommended to implement {@link #surfaceRedrawNeeded} for |
| * compatibility with older versions of the platform. |
| * |
| * @param holder The SurfaceHolder which needs redrawing. |
| * @param drawingFinished A runnable to signal completion. This may be invoked |
| * from any thread. |
| * |
| */ |
| default void surfaceRedrawNeededAsync(@NonNull SurfaceHolder holder, |
| @NonNull Runnable drawingFinished) { |
| surfaceRedrawNeeded(holder); |
| drawingFinished.run(); |
| } |
| } |
| |
| /** |
| * Add a Callback interface for this holder. There can several Callback |
| * interfaces associated with a holder. |
| * |
| * @param callback The new Callback interface. |
| */ |
| public void addCallback(Callback callback); |
| |
| /** |
| * Removes a previously added Callback interface from this holder. |
| * |
| * @param callback The Callback interface to remove. |
| */ |
| public void removeCallback(Callback callback); |
| |
| /** |
| * Use this method to find out if the surface is in the process of being |
| * created from Callback methods. This is intended to be used with |
| * {@link Callback#surfaceChanged}. |
| * |
| * @return true if the surface is in the process of being created. |
| */ |
| public boolean isCreating(); |
| |
| /** |
| * Sets the surface's type. |
| * |
| * @deprecated this is ignored, this value is set automatically when needed. |
| */ |
| @Deprecated |
| public void setType(int type); |
| |
| /** |
| * Make the surface a fixed size. It will never change from this size. |
| * When working with a {@link SurfaceView}, this must be called from the |
| * same thread running the SurfaceView's window. |
| * |
| * @param width The surface's width. |
| * @param height The surface's height. |
| */ |
| public void setFixedSize(int width, int height); |
| |
| /** |
| * Allow the surface to resized based on layout of its container (this is |
| * the default). When this is enabled, you should monitor |
| * {@link Callback#surfaceChanged} for changes to the size of the surface. |
| * When working with a {@link SurfaceView}, this must be called from the |
| * same thread running the SurfaceView's window. |
| */ |
| public void setSizeFromLayout(); |
| |
| /** |
| * Set the desired PixelFormat of the surface. The default is OPAQUE. |
| * When working with a {@link SurfaceView}, this must be called from the |
| * same thread running the SurfaceView's window. |
| * |
| * @param format A constant from PixelFormat. |
| * |
| * @see android.graphics.PixelFormat |
| */ |
| public void setFormat(int format); |
| |
| /** |
| * Enable or disable option to keep the screen turned on while this |
| * surface is displayed. The default is false, allowing it to turn off. |
| * This is safe to call from any thread. |
| * |
| * @param screenOn Set to true to force the screen to stay on, false |
| * to allow it to turn off. |
| */ |
| public void setKeepScreenOn(boolean screenOn); |
| |
| /** |
| * Start editing the pixels in the surface. The returned Canvas can be used |
| * to draw into the surface's bitmap. A null is returned if the surface has |
| * not been created or otherwise cannot be edited. You will usually need |
| * to implement {@link Callback#surfaceCreated Callback.surfaceCreated} |
| * to find out when the Surface is available for use. |
| * |
| * <p>The content of the Surface is never preserved between unlockCanvas() and |
| * lockCanvas(), for this reason, every pixel within the Surface area |
| * must be written. The only exception to this rule is when a dirty |
| * rectangle is specified, in which case, non-dirty pixels will be |
| * preserved. |
| * |
| * <p>If you call this repeatedly when the Surface is not ready (before |
| * {@link Callback#surfaceCreated Callback.surfaceCreated} or after |
| * {@link Callback#surfaceDestroyed Callback.surfaceDestroyed}), your calls |
| * will be throttled to a slow rate in order to avoid consuming CPU. |
| * |
| * <p>If null is not returned, this function internally holds a lock until |
| * the corresponding {@link #unlockCanvasAndPost} call, preventing |
| * {@link SurfaceView} from creating, destroying, or modifying the surface |
| * while it is being drawn. This can be more convenient than accessing |
| * the Surface directly, as you do not need to do special synchronization |
| * with a drawing thread in {@link Callback#surfaceDestroyed |
| * Callback.surfaceDestroyed}. |
| * |
| * @return Canvas Use to draw into the surface. |
| */ |
| public Canvas lockCanvas(); |
| |
| |
| /** |
| * Just like {@link #lockCanvas()} but allows specification of a dirty rectangle. |
| * Every |
| * pixel within that rectangle must be written; however pixels outside |
| * the dirty rectangle will be preserved by the next call to lockCanvas(). |
| * |
| * @see android.view.SurfaceHolder#lockCanvas |
| * |
| * @param dirty Area of the Surface that will be modified. |
| * @return Canvas Use to draw into the surface. |
| */ |
| public Canvas lockCanvas(Rect dirty); |
| |
| /** |
| * <p>Just like {@link #lockCanvas()} but the returned canvas is hardware-accelerated. |
| * |
| * <p>See the <a href="{@docRoot}guide/topics/graphics/hardware-accel.html#unsupported"> |
| * unsupported drawing operations</a> for a list of what is and isn't |
| * supported in a hardware-accelerated canvas. |
| * |
| * @return Canvas Use to draw into the surface. |
| * @throws IllegalStateException If the canvas cannot be locked. |
| */ |
| default Canvas lockHardwareCanvas() { |
| throw new IllegalStateException("This SurfaceHolder doesn't support lockHardwareCanvas"); |
| } |
| |
| /** |
| * Finish editing pixels in the surface. After this call, the surface's |
| * current pixels will be shown on the screen, but its content is lost, |
| * in particular there is no guarantee that the content of the Surface |
| * will remain unchanged when lockCanvas() is called again. |
| * |
| * @see #lockCanvas() |
| * |
| * @param canvas The Canvas previously returned by lockCanvas(). |
| */ |
| public void unlockCanvasAndPost(Canvas canvas); |
| |
| /** |
| * Retrieve the current size of the surface. Note: do not modify the |
| * returned Rect. This is only safe to call from the thread of |
| * {@link SurfaceView}'s window, or while inside of |
| * {@link #lockCanvas()}. |
| * |
| * @return Rect The surface's dimensions. The left and top are always 0. |
| */ |
| public Rect getSurfaceFrame(); |
| |
| /** |
| * Direct access to the surface object. The Surface may not always be |
| * available -- for example when using a {@link SurfaceView} the holder's |
| * Surface is not created until the view has been attached to the window |
| * manager and performed a layout in order to determine the dimensions |
| * and screen position of the Surface. You will thus usually need |
| * to implement {@link Callback#surfaceCreated Callback.surfaceCreated} |
| * to find out when the Surface is available for use. |
| * |
| * <p>Note that if you directly access the Surface from another thread, |
| * it is critical that you correctly implement |
| * {@link Callback#surfaceCreated Callback.surfaceCreated} and |
| * {@link Callback#surfaceDestroyed Callback.surfaceDestroyed} to ensure |
| * that thread only accesses the Surface while it is valid, and that the |
| * Surface does not get destroyed while the thread is using it. |
| * |
| * <p>This method is intended to be used by frameworks which often need |
| * direct access to the Surface object (usually to pass it to native code). |
| * |
| * @return Surface The surface. |
| */ |
| public Surface getSurface(); |
| } |