android.widget.Magnifier Maven / Gradle / Ivy
Go to download
Show more of this group Show more artifacts with this name
Show all versions of android-all Show documentation
Show all versions of android-all Show documentation
A library jar that provides APIs for Applications written for the Google Android Platform.
/*
* Copyright (C) 2017 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.widget;
import android.annotation.FloatRange;
import android.annotation.NonNull;
import android.annotation.Nullable;
import android.annotation.TestApi;
import android.annotation.UiThread;
import android.content.Context;
import android.content.res.Resources;
import android.content.res.TypedArray;
import android.graphics.Bitmap;
import android.graphics.Color;
import android.graphics.Outline;
import android.graphics.Paint;
import android.graphics.PixelFormat;
import android.graphics.Point;
import android.graphics.PointF;
import android.graphics.Rect;
import android.os.Handler;
import android.os.HandlerThread;
import android.os.Message;
import android.view.ContextThemeWrapper;
import android.view.Display;
import android.view.DisplayListCanvas;
import android.view.PixelCopy;
import android.view.RenderNode;
import android.view.Surface;
import android.view.SurfaceControl;
import android.view.SurfaceHolder;
import android.view.SurfaceSession;
import android.view.SurfaceView;
import android.view.ThreadedRenderer;
import android.view.View;
import android.view.ViewRootImpl;
import com.android.internal.R;
import com.android.internal.util.Preconditions;
/**
* Android magnifier widget. Can be used by any view which is attached to a window.
*/
@UiThread
public final class Magnifier {
// Use this to specify that a previous configuration value does not exist.
private static final int NONEXISTENT_PREVIOUS_CONFIG_VALUE = -1;
// The callbacks of the pixel copy requests will be invoked on
// the Handler of this Thread when the copy is finished.
private static final HandlerThread sPixelCopyHandlerThread =
new HandlerThread("magnifier pixel copy result handler");
// The view to which this magnifier is attached.
private final View mView;
// The coordinates of the view in the surface.
private final int[] mViewCoordinatesInSurface;
// The window containing the magnifier.
private InternalPopupWindow mWindow;
// The width of the window containing the magnifier.
private final int mWindowWidth;
// The height of the window containing the magnifier.
private final int mWindowHeight;
// The zoom applied to the view region copied to the magnifier window.
private final float mZoom;
// The width of the bitmaps where the magnifier content is copied.
private final int mBitmapWidth;
// The height of the bitmaps where the magnifier content is copied.
private final int mBitmapHeight;
// The elevation of the window containing the magnifier.
private final float mWindowElevation;
// The corner radius of the window containing the magnifier.
private final float mWindowCornerRadius;
// The parent surface for the magnifier surface.
private SurfaceInfo mParentSurface;
// The surface where the content will be copied from.
private SurfaceInfo mContentCopySurface;
// The center coordinates of the window containing the magnifier.
private final Point mWindowCoords = new Point();
// The center coordinates of the content to be magnified,
// which can potentially contain a region outside the magnified view.
private final Point mCenterZoomCoords = new Point();
// The center coordinates of the content to be magnified,
// clamped inside the visible region of the magnified view.
private final Point mClampedCenterZoomCoords = new Point();
// Variables holding previous states, used for detecting redundant calls and invalidation.
private final Point mPrevStartCoordsInSurface = new Point(
NONEXISTENT_PREVIOUS_CONFIG_VALUE, NONEXISTENT_PREVIOUS_CONFIG_VALUE);
private final PointF mPrevPosInView = new PointF(
NONEXISTENT_PREVIOUS_CONFIG_VALUE, NONEXISTENT_PREVIOUS_CONFIG_VALUE);
// Rectangle defining the view surface area we pixel copy content from.
private final Rect mPixelCopyRequestRect = new Rect();
// Lock to synchronize between the UI thread and the thread that handles pixel copy results.
// Only sync mWindow writes from UI thread with mWindow reads from sPixelCopyHandlerThread.
private final Object mLock = new Object();
/**
* Initializes a magnifier.
*
* @param view the view for which this magnifier is attached
*/
public Magnifier(@NonNull View view) {
mView = Preconditions.checkNotNull(view);
final Context context = mView.getContext();
mWindowWidth = context.getResources().getDimensionPixelSize(R.dimen.magnifier_width);
mWindowHeight = context.getResources().getDimensionPixelSize(R.dimen.magnifier_height);
mWindowElevation = context.getResources().getDimension(R.dimen.magnifier_elevation);
mWindowCornerRadius = getDeviceDefaultDialogCornerRadius();
mZoom = context.getResources().getFloat(R.dimen.magnifier_zoom_scale);
mBitmapWidth = Math.round(mWindowWidth / mZoom);
mBitmapHeight = Math.round(mWindowHeight / mZoom);
// The view's surface coordinates will not be updated until the magnifier is first shown.
mViewCoordinatesInSurface = new int[2];
}
static {
sPixelCopyHandlerThread.start();
}
/**
* Returns the device default theme dialog corner radius attribute.
* We retrieve this from the device default theme to avoid
* using the values set in the custom application themes.
*/
private float getDeviceDefaultDialogCornerRadius() {
final Context deviceDefaultContext =
new ContextThemeWrapper(mView.getContext(), R.style.Theme_DeviceDefault);
final TypedArray ta = deviceDefaultContext.obtainStyledAttributes(
new int[]{android.R.attr.dialogCornerRadius});
final float dialogCornerRadius = ta.getDimension(0, 0);
ta.recycle();
return dialogCornerRadius;
}
/**
* Shows the magnifier on the screen.
*
* @param xPosInView horizontal coordinate of the center point of the magnifier source relative
* to the view. The lower end is clamped to 0 and the higher end is clamped to the view
* width.
* @param yPosInView vertical coordinate of the center point of the magnifier source
* relative to the view. The lower end is clamped to 0 and the higher end is clamped to
* the view height.
*/
public void show(@FloatRange(from = 0) float xPosInView,
@FloatRange(from = 0) float yPosInView) {
xPosInView = Math.max(0, Math.min(xPosInView, mView.getWidth()));
yPosInView = Math.max(0, Math.min(yPosInView, mView.getHeight()));
obtainSurfaces();
obtainContentCoordinates(xPosInView, yPosInView);
obtainWindowCoordinates();
final int startX = mClampedCenterZoomCoords.x - mBitmapWidth / 2;
final int startY = mClampedCenterZoomCoords.y - mBitmapHeight / 2;
if (xPosInView != mPrevPosInView.x || yPosInView != mPrevPosInView.y) {
if (mWindow == null) {
synchronized (mLock) {
mWindow = new InternalPopupWindow(mView.getContext(), mView.getDisplay(),
mParentSurface.mSurface,
mWindowWidth, mWindowHeight, mWindowElevation, mWindowCornerRadius,
Handler.getMain() /* draw the magnifier on the UI thread */, mLock,
mCallback);
}
}
performPixelCopy(startX, startY, true /* update window position */);
mPrevPosInView.x = xPosInView;
mPrevPosInView.y = yPosInView;
}
}
/**
* Dismisses the magnifier from the screen. Calling this on a dismissed magnifier is a no-op.
*/
public void dismiss() {
if (mWindow != null) {
synchronized (mLock) {
mWindow.destroy();
mWindow = null;
}
mPrevPosInView.x = NONEXISTENT_PREVIOUS_CONFIG_VALUE;
mPrevPosInView.y = NONEXISTENT_PREVIOUS_CONFIG_VALUE;
mPrevStartCoordsInSurface.x = NONEXISTENT_PREVIOUS_CONFIG_VALUE;
mPrevStartCoordsInSurface.y = NONEXISTENT_PREVIOUS_CONFIG_VALUE;
}
}
/**
* Forces the magnifier to update its content. It uses the previous coordinates passed to
* {@link #show(float, float)}. This only happens if the magnifier is currently showing.
*/
public void update() {
if (mWindow != null) {
obtainSurfaces();
// Update the content shown in the magnifier.
performPixelCopy(mPrevStartCoordsInSurface.x, mPrevStartCoordsInSurface.y,
false /* update window position */);
}
}
/**
* @return The width of the magnifier window, in pixels.
*/
public int getWidth() {
return mWindowWidth;
}
/**
* @return The height of the magnifier window, in pixels.
*/
public int getHeight() {
return mWindowHeight;
}
/**
* @return The zoom applied to the magnified view region copied to the magnifier window.
* If the zoom is x and the magnifier window size is (width, height), the original size
* of the content copied in the magnifier will be (width / x, height / x).
*/
public float getZoom() {
return mZoom;
}
/**
* @hide
*
* @return The top left coordinates of the magnifier, relative to the parent window.
*/
@Nullable
public Point getWindowCoords() {
if (mWindow == null) {
return null;
}
final Rect surfaceInsets = mView.getViewRootImpl().mWindowAttributes.surfaceInsets;
return new Point(mWindow.mLastDrawContentPositionX - surfaceInsets.left,
mWindow.mLastDrawContentPositionY - surfaceInsets.top);
}
/**
* Retrieves the surfaces used by the magnifier:
* - a parent surface for the magnifier surface. This will usually be the main app window.
* - a surface where the magnified content will be copied from. This will be the main app
* window unless the magnified view is a SurfaceView, in which case its backing surface
* will be used.
*/
private void obtainSurfaces() {
// Get the main window surface.
SurfaceInfo validMainWindowSurface = SurfaceInfo.NULL;
if (mView.getViewRootImpl() != null) {
final ViewRootImpl viewRootImpl = mView.getViewRootImpl();
final Surface mainWindowSurface = viewRootImpl.mSurface;
if (mainWindowSurface != null && mainWindowSurface.isValid()) {
final Rect surfaceInsets = viewRootImpl.mWindowAttributes.surfaceInsets;
final int surfaceWidth =
viewRootImpl.getWidth() + surfaceInsets.left + surfaceInsets.right;
final int surfaceHeight =
viewRootImpl.getHeight() + surfaceInsets.top + surfaceInsets.bottom;
validMainWindowSurface =
new SurfaceInfo(mainWindowSurface, surfaceWidth, surfaceHeight, true);
}
}
// Get the surface backing the magnified view, if it is a SurfaceView.
SurfaceInfo validSurfaceViewSurface = SurfaceInfo.NULL;
if (mView instanceof SurfaceView) {
final SurfaceHolder surfaceHolder = ((SurfaceView) mView).getHolder();
final Surface surfaceViewSurface = surfaceHolder.getSurface();
if (surfaceViewSurface != null && surfaceViewSurface.isValid()) {
final Rect surfaceFrame = surfaceHolder.getSurfaceFrame();
validSurfaceViewSurface = new SurfaceInfo(surfaceViewSurface,
surfaceFrame.right, surfaceFrame.bottom, false);
}
}
// Choose the parent surface for the magnifier and the source surface for the content.
mParentSurface = validMainWindowSurface != SurfaceInfo.NULL
? validMainWindowSurface : validSurfaceViewSurface;
mContentCopySurface = mView instanceof SurfaceView
? validSurfaceViewSurface : validMainWindowSurface;
}
/**
* Computes the coordinates of the center of the content going to be displayed in the
* magnifier. These are relative to the surface the content is copied from.
*/
private void obtainContentCoordinates(final float xPosInView, final float yPosInView) {
final float posX;
final float posY;
mView.getLocationInSurface(mViewCoordinatesInSurface);
if (mView instanceof SurfaceView) {
// No offset required if the backing Surface matches the size of the SurfaceView.
posX = xPosInView;
posY = yPosInView;
} else {
posX = xPosInView + mViewCoordinatesInSurface[0];
posY = yPosInView + mViewCoordinatesInSurface[1];
}
mCenterZoomCoords.x = Math.round(posX);
mCenterZoomCoords.y = Math.round(posY);
// Clamp the x location to avoid magnifying content which does not belong
// to the magnified view. This will not take into account overlapping views.
final Rect viewVisibleRegion = new Rect();
mView.getGlobalVisibleRect(viewVisibleRegion);
if (mView.getViewRootImpl() != null) {
// Clamping coordinates relative to the surface, not to the window.
final Rect surfaceInsets = mView.getViewRootImpl().mWindowAttributes.surfaceInsets;
viewVisibleRegion.offset(surfaceInsets.left, surfaceInsets.top);
}
if (mView instanceof SurfaceView) {
// If we copy content from a SurfaceView, clamp coordinates relative to it.
viewVisibleRegion.offset(-mViewCoordinatesInSurface[0], -mViewCoordinatesInSurface[1]);
}
mClampedCenterZoomCoords.x = Math.max(viewVisibleRegion.left + mBitmapWidth / 2, Math.min(
mCenterZoomCoords.x, viewVisibleRegion.right - mBitmapWidth / 2));
mClampedCenterZoomCoords.y = mCenterZoomCoords.y;
}
private void obtainWindowCoordinates() {
// Compute the position of the magnifier window. Again, this has to be relative to the
// surface of the magnified view, as this surface is the parent of the magnifier surface.
final int verticalOffset = mView.getContext().getResources().getDimensionPixelSize(
R.dimen.magnifier_offset);
mWindowCoords.x = mCenterZoomCoords.x - mWindowWidth / 2;
mWindowCoords.y = mCenterZoomCoords.y - mWindowHeight / 2 - verticalOffset;
if (mParentSurface != mContentCopySurface) {
mWindowCoords.x += mViewCoordinatesInSurface[0];
mWindowCoords.y += mViewCoordinatesInSurface[1];
}
}
private void performPixelCopy(final int startXInSurface, final int startYInSurface,
final boolean updateWindowPosition) {
if (mContentCopySurface.mSurface == null || !mContentCopySurface.mSurface.isValid()) {
return;
}
// Clamp copy coordinates inside the surface to avoid displaying distorted content.
final int clampedStartXInSurface = Math.max(0,
Math.min(startXInSurface, mContentCopySurface.mWidth - mBitmapWidth));
final int clampedStartYInSurface = Math.max(0,
Math.min(startYInSurface, mContentCopySurface.mHeight - mBitmapHeight));
// Clamp window coordinates inside the parent surface, to avoid displaying
// the magnifier out of screen or overlapping with system insets.
final Rect windowBounds;
if (mParentSurface.mIsMainWindowSurface) {
final Rect systemInsets = mView.getRootWindowInsets().getSystemWindowInsets();
windowBounds = new Rect(systemInsets.left, systemInsets.top,
mParentSurface.mWidth - systemInsets.right,
mParentSurface.mHeight - systemInsets.bottom);
} else {
windowBounds = new Rect(0, 0, mParentSurface.mWidth, mParentSurface.mHeight);
}
final int windowCoordsX = Math.max(windowBounds.left,
Math.min(windowBounds.right - mWindowWidth, mWindowCoords.x));
final int windowCoordsY = Math.max(windowBounds.top,
Math.min(windowBounds.bottom - mWindowHeight, mWindowCoords.y));
// Perform the pixel copy.
mPixelCopyRequestRect.set(clampedStartXInSurface,
clampedStartYInSurface,
clampedStartXInSurface + mBitmapWidth,
clampedStartYInSurface + mBitmapHeight);
final InternalPopupWindow currentWindowInstance = mWindow;
final Bitmap bitmap =
Bitmap.createBitmap(mBitmapWidth, mBitmapHeight, Bitmap.Config.ARGB_8888);
PixelCopy.request(mContentCopySurface.mSurface, mPixelCopyRequestRect, bitmap,
result -> {
synchronized (mLock) {
if (mWindow != currentWindowInstance) {
// The magnifier was dismissed (and maybe shown again) in the meantime.
return;
}
if (updateWindowPosition) {
// TODO: pull the position update outside #performPixelCopy
mWindow.setContentPositionForNextDraw(windowCoordsX, windowCoordsY);
}
mWindow.updateContent(bitmap);
}
},
sPixelCopyHandlerThread.getThreadHandler());
mPrevStartCoordsInSurface.x = startXInSurface;
mPrevStartCoordsInSurface.y = startYInSurface;
}
/**
* Contains a surface and metadata corresponding to it.
*/
private static class SurfaceInfo {
public static final SurfaceInfo NULL = new SurfaceInfo(null, 0, 0, false);
private Surface mSurface;
private int mWidth;
private int mHeight;
private boolean mIsMainWindowSurface;
SurfaceInfo(final Surface surface, final int width, final int height,
final boolean isMainWindowSurface) {
mSurface = surface;
mWidth = width;
mHeight = height;
mIsMainWindowSurface = isMainWindowSurface;
}
}
/**
* Magnifier's own implementation of PopupWindow-similar floating window.
* This exists to ensure frame-synchronization between window position updates and window
* content updates. By using a PopupWindow, these events would happen in different frames,
* producing a shakiness effect for the magnifier content.
*/
private static class InternalPopupWindow {
// The alpha set on the magnifier's content, which defines how
// prominent the white background is.
private static final int CONTENT_BITMAP_ALPHA = 242;
// The z of the magnifier surface, defining its z order in the list of
// siblings having the same parent surface (usually the main app surface).
private static final int SURFACE_Z = 5;
// Display associated to the view the magnifier is attached to.
private final Display mDisplay;
// The size of the content of the magnifier.
private final int mContentWidth;
private final int mContentHeight;
// The size of the allocated surface.
private final int mSurfaceWidth;
private final int mSurfaceHeight;
// The insets of the content inside the allocated surface.
private final int mOffsetX;
private final int mOffsetY;
// The surface we allocate for the magnifier content + shadow.
private final SurfaceSession mSurfaceSession;
private final SurfaceControl mSurfaceControl;
private final Surface mSurface;
// The renderer used for the allocated surface.
private final ThreadedRenderer.SimpleRenderer mRenderer;
// The RenderNode used to draw the magnifier content in the surface.
private final RenderNode mBitmapRenderNode;
// The job that will be post'd to apply the pending magnifier updates to the surface.
private final Runnable mMagnifierUpdater;
// The handler where the magnifier updater jobs will be post'd.
private final Handler mHandler;
// The callback to be run after the next draw.
private Callback mCallback;
// The position of the magnifier content when the last draw was requested.
private int mLastDrawContentPositionX;
private int mLastDrawContentPositionY;
// Members below describe the state of the magnifier. Reads/writes to them
// have to be synchronized between the UI thread and the thread that handles
// the pixel copy results. This is the purpose of mLock.
private final Object mLock;
// Whether a magnifier frame draw is currently pending in the UI thread queue.
private boolean mFrameDrawScheduled;
// The content bitmap.
private Bitmap mBitmap;
// Whether the next draw will be the first one for the current instance.
private boolean mFirstDraw = true;
// The window position in the parent surface. Might be applied during the next draw,
// when mPendingWindowPositionUpdate is true.
private int mWindowPositionX;
private int mWindowPositionY;
private boolean mPendingWindowPositionUpdate;
// The lock used to synchronize the UI and render threads when a #destroy
// is performed on the UI thread and a frame callback on the render thread.
// When both mLock and mDestroyLock need to be held at the same time,
// mDestroyLock should be acquired before mLock in order to avoid deadlocks.
private final Object mDestroyLock = new Object();
InternalPopupWindow(final Context context, final Display display,
final Surface parentSurface,
final int width, final int height, final float elevation, final float cornerRadius,
final Handler handler, final Object lock, final Callback callback) {
mDisplay = display;
mLock = lock;
mCallback = callback;
mContentWidth = width;
mContentHeight = height;
mOffsetX = (int) (0.1f * width);
mOffsetY = (int) (0.1f * height);
// Setup the surface we will use for drawing the content and shadow.
mSurfaceWidth = mContentWidth + 2 * mOffsetX;
mSurfaceHeight = mContentHeight + 2 * mOffsetY;
mSurfaceSession = new SurfaceSession(parentSurface);
mSurfaceControl = new SurfaceControl.Builder(mSurfaceSession)
.setFormat(PixelFormat.TRANSLUCENT)
.setSize(mSurfaceWidth, mSurfaceHeight)
.setName("magnifier surface")
.setFlags(SurfaceControl.HIDDEN)
.build();
mSurface = new Surface();
mSurface.copyFrom(mSurfaceControl);
// Setup the RenderNode tree. The root has only one child, which contains the bitmap.
mRenderer = new ThreadedRenderer.SimpleRenderer(
context,
"magnifier renderer",
mSurface
);
mBitmapRenderNode = createRenderNodeForBitmap(
"magnifier content",
elevation,
cornerRadius
);
final DisplayListCanvas canvas = mRenderer.getRootNode().start(width, height);
try {
canvas.insertReorderBarrier();
canvas.drawRenderNode(mBitmapRenderNode);
canvas.insertInorderBarrier();
} finally {
mRenderer.getRootNode().end(canvas);
}
// Initialize the update job and the handler where this will be post'd.
mHandler = handler;
mMagnifierUpdater = this::doDraw;
mFrameDrawScheduled = false;
}
private RenderNode createRenderNodeForBitmap(final String name,
final float elevation, final float cornerRadius) {
final RenderNode bitmapRenderNode = RenderNode.create(name, null);
// Define the position of the bitmap in the parent render node. The surface regions
// outside the bitmap are used to draw elevation.
bitmapRenderNode.setLeftTopRightBottom(mOffsetX, mOffsetY,
mOffsetX + mContentWidth, mOffsetY + mContentHeight);
bitmapRenderNode.setElevation(elevation);
final Outline outline = new Outline();
outline.setRoundRect(0, 0, mContentWidth, mContentHeight, cornerRadius);
outline.setAlpha(1.0f);
bitmapRenderNode.setOutline(outline);
bitmapRenderNode.setClipToOutline(true);
// Create a dummy draw, which will be replaced later with real drawing.
final DisplayListCanvas canvas = bitmapRenderNode.start(mContentWidth, mContentHeight);
try {
canvas.drawColor(0xFF00FF00);
} finally {
bitmapRenderNode.end(canvas);
}
return bitmapRenderNode;
}
/**
* Sets the position of the magnifier content relative to the parent surface.
* The position update will happen in the same frame with the next draw.
* The method has to be called in a context that holds {@link #mLock}.
*
* @param contentX the x coordinate of the content
* @param contentY the y coordinate of the content
*/
public void setContentPositionForNextDraw(final int contentX, final int contentY) {
mWindowPositionX = contentX - mOffsetX;
mWindowPositionY = contentY - mOffsetY;
mPendingWindowPositionUpdate = true;
requestUpdate();
}
/**
* Sets the content that should be displayed in the magnifier.
* The update happens immediately, and possibly triggers a pending window movement set
* by {@link #setContentPositionForNextDraw(int, int)}.
* The method has to be called in a context that holds {@link #mLock}.
*
* @param bitmap the content bitmap
*/
public void updateContent(final @NonNull Bitmap bitmap) {
if (mBitmap != null) {
mBitmap.recycle();
}
mBitmap = bitmap;
requestUpdate();
}
private void requestUpdate() {
if (mFrameDrawScheduled) {
return;
}
final Message request = Message.obtain(mHandler, mMagnifierUpdater);
request.setAsynchronous(true);
request.sendToTarget();
mFrameDrawScheduled = true;
}
/**
* Destroys this instance.
*/
public void destroy() {
synchronized (mDestroyLock) {
mSurface.destroy();
}
synchronized (mLock) {
mRenderer.destroy();
mSurfaceControl.destroy();
mSurfaceSession.kill();
mBitmapRenderNode.destroy();
mHandler.removeCallbacks(mMagnifierUpdater);
if (mBitmap != null) {
mBitmap.recycle();
}
}
}
private void doDraw() {
final ThreadedRenderer.FrameDrawingCallback callback;
// Draw the current bitmap to the surface, and prepare the callback which updates the
// surface position. These have to be in the same synchronized block, in order to
// guarantee the consistency between the bitmap content and the surface position.
synchronized (mLock) {
if (!mSurface.isValid()) {
// Probably #destroy() was called for the current instance, so we skip the draw.
return;
}
final DisplayListCanvas canvas =
mBitmapRenderNode.start(mContentWidth, mContentHeight);
try {
canvas.drawColor(Color.WHITE);
final Rect srcRect = new Rect(0, 0, mBitmap.getWidth(), mBitmap.getHeight());
final Rect dstRect = new Rect(0, 0, mContentWidth, mContentHeight);
final Paint paint = new Paint();
paint.setFilterBitmap(true);
paint.setAlpha(CONTENT_BITMAP_ALPHA);
canvas.drawBitmap(mBitmap, srcRect, dstRect, paint);
} finally {
mBitmapRenderNode.end(canvas);
}
if (mPendingWindowPositionUpdate || mFirstDraw) {
// If the window has to be shown or moved, defer this until the next draw.
final boolean firstDraw = mFirstDraw;
mFirstDraw = false;
final boolean updateWindowPosition = mPendingWindowPositionUpdate;
mPendingWindowPositionUpdate = false;
final int pendingX = mWindowPositionX;
final int pendingY = mWindowPositionY;
callback = frame -> {
synchronized (mDestroyLock) {
if (!mSurface.isValid()) {
return;
}
synchronized (mLock) {
mRenderer.setLightCenter(mDisplay, pendingX, pendingY);
// Show or move the window at the content draw frame.
SurfaceControl.openTransaction();
mSurfaceControl.deferTransactionUntil(mSurface, frame);
if (updateWindowPosition) {
mSurfaceControl.setPosition(pendingX, pendingY);
}
if (firstDraw) {
mSurfaceControl.setLayer(SURFACE_Z);
mSurfaceControl.show();
}
SurfaceControl.closeTransaction();
}
}
};
} else {
callback = null;
}
mLastDrawContentPositionX = mWindowPositionX + mOffsetX;
mLastDrawContentPositionY = mWindowPositionY + mOffsetY;
mFrameDrawScheduled = false;
}
mRenderer.draw(callback);
if (mCallback != null) {
mCallback.onOperationComplete();
}
}
}
// The rest of the file consists of test APIs.
/**
* See {@link #setOnOperationCompleteCallback(Callback)}.
*/
@TestApi
private Callback mCallback;
/**
* Sets a callback which will be invoked at the end of the next
* {@link #show(float, float)} or {@link #update()} operation.
*
* @hide
*/
@TestApi
public void setOnOperationCompleteCallback(final Callback callback) {
mCallback = callback;
if (mWindow != null) {
mWindow.mCallback = callback;
}
}
/**
* @return the content being currently displayed in the magnifier, as bitmap
*
* @hide
*/
@TestApi
public @Nullable Bitmap getContent() {
if (mWindow == null) {
return null;
}
synchronized (mWindow.mLock) {
return Bitmap.createScaledBitmap(mWindow.mBitmap, mWindowWidth, mWindowHeight, true);
}
}
/**
* @return the position of the magnifier window relative to the screen
*
* @hide
*/
@TestApi
public Rect getWindowPositionOnScreen() {
final int[] viewLocationOnScreen = new int[2];
mView.getLocationOnScreen(viewLocationOnScreen);
final int[] viewLocationInSurface = new int[2];
mView.getLocationInSurface(viewLocationInSurface);
final int left = mWindowCoords.x + viewLocationOnScreen[0] - viewLocationInSurface[0];
final int top = mWindowCoords.y + viewLocationOnScreen[1] - viewLocationInSurface[1];
return new Rect(left, top, left + mWindowWidth, top + mWindowHeight);
}
/**
* @return the size of the magnifier window in dp
*
* @hide
*/
@TestApi
public static PointF getMagnifierDefaultSize() {
final Resources resources = Resources.getSystem();
final float density = resources.getDisplayMetrics().density;
final PointF size = new PointF();
size.x = resources.getDimension(R.dimen.magnifier_width) / density;
size.y = resources.getDimension(R.dimen.magnifier_height) / density;
return size;
}
/**
* @hide
*/
@TestApi
public interface Callback {
/**
* Callback called after the drawing for a magnifier update has happened.
*/
void onOperationComplete();
}
}