Added takeScreenshot API to WindowOrganizer

Added requests to take screenshot of a Window that's organized
by the client. The resulting screenshot will be attached to a
SurfaceControl and reparented to the requested window's parent. The
client will be responsible for showing, setting z order, etc. They can
also re-parent to another place in the hierarchy. The default is to
parent to the window's parent since that's usually where a screenshot is
placed.

Test: Builds
Bug: 152114574
Change-Id: I5c829e029f3528fdb382842e9f0474097e01cb2e
Merged-In: I5c829e029f3528fdb382842e9f0474097e01cb2e

core/java/android/window/IWindowOrganizerController.aidl

@@ -16,9 +16,12 @@
 
 package android.window;
 
+import android.view.SurfaceControl;
+
 import android.window.IDisplayAreaOrganizerController;
 import android.window.ITaskOrganizerController;
 import android.window.IWindowContainerTransactionCallback;
+import android.window.WindowContainerToken;
 import android.window.WindowContainerTransaction;
 
 /** @hide */
@@ -47,4 +50,15 @@ interface IWindowOrganizerController {
 
     /** @return An interface enabling the management of display area organizers. */
     IDisplayAreaOrganizerController getDisplayAreaOrganizerController();
+
+    /**
+     * Take a screenshot of the requested Window token and place the content of the screenshot into
+     * outSurfaceControl. The SurfaceControl will be a child of the token's parent, so it will be
+     * a sibling of the token's window
+     * @param token The token for the WindowContainer that should get a screenshot taken.
+     * @param outSurfaceControl The SurfaceControl where the screenshot will be attached.
+     *
+     * @return true if the screenshot was successful, false otherwise.
+     */
+    boolean takeScreenshot(in WindowContainerToken token, out SurfaceControl outSurfaceControl);
 }

core/java/android/window/WindowOrganizer.java

@@ -17,11 +17,13 @@
 package android.window;
 
 import android.annotation.NonNull;
+import android.annotation.Nullable;
 import android.annotation.RequiresPermission;
 import android.annotation.TestApi;
 import android.app.ActivityTaskManager;
 import android.os.RemoteException;
 import android.util.Singleton;
+import android.view.SurfaceControl;
 
 /**
  * Base class for organizing specific types of windows like Tasks and DisplayAreas
@@ -63,6 +65,28 @@ public class WindowOrganizer {
         }
     }
 
+    /**
+     * Take a screenshot for a specified Window
+     * @param token The token for the WindowContainer that should get a screenshot taken.
+     * @return A SurfaceControl where the screenshot will be attached, or null if failed.
+     *
+     * @hide
+     */
+    @Nullable
+    @RequiresPermission(android.Manifest.permission.READ_FRAME_BUFFER)
+    public static SurfaceControl takeScreenshot(@NonNull WindowContainerToken token) {
+        try {
+            SurfaceControl surfaceControl = new SurfaceControl();
+            if (getWindowOrganizerController().takeScreenshot(token, surfaceControl)) {
+                return surfaceControl;
+            } else {
+                return null;
+            }
+        } catch (RemoteException e) {
+            throw e.rethrowFromSystemServer();
+        }
+    }
+
     @RequiresPermission(android.Manifest.permission.MANAGE_ACTIVITY_STACKS)
     static IWindowOrganizerController getWindowOrganizerController() {
         return IWindowOrganizerControllerSingleton.get();

services/core/java/com/android/server/wm/WindowOrganizerController.java

@@ -17,6 +17,7 @@
 package com.android.server.wm;
 
 import static android.Manifest.permission.MANAGE_ACTIVITY_STACKS;
+import static android.Manifest.permission.READ_FRAME_BUFFER;
 
 import static com.android.server.wm.ActivityStackSupervisor.PRESERVE_WINDOWS;
 import static com.android.server.wm.Task.FLAG_FORCE_HIDDEN_FOR_TASK_ORG;
@@ -26,17 +27,20 @@ import static com.android.server.wm.WindowContainer.POSITION_TOP;
 import android.app.WindowConfiguration;
 import android.content.pm.ActivityInfo;
 import android.content.res.Configuration;
+import android.graphics.PixelFormat;
 import android.graphics.Rect;
 import android.os.Binder;
 import android.os.IBinder;
 import android.os.RemoteException;
 import android.util.ArraySet;
 import android.util.Slog;
+import android.view.Surface;
 import android.view.SurfaceControl;
 import android.window.IDisplayAreaOrganizerController;
 import android.window.ITaskOrganizerController;
 import android.window.IWindowContainerTransactionCallback;
 import android.window.IWindowOrganizerController;
+import android.window.WindowContainerToken;
 import android.window.WindowContainerTransaction;
 
 import com.android.internal.util.function.pooled.PooledConsumer;
@@ -372,6 +376,40 @@ class WindowOrganizerController extends IWindowOrganizerController.Stub
         mTransactionCallbacksByPendingSyncId.remove(mSyncId);
     }
 
+    @Override
+    public boolean takeScreenshot(WindowContainerToken token, SurfaceControl outSurfaceControl) {
+        mService.mAmInternal.enforceCallingPermission(READ_FRAME_BUFFER, "takeScreenshot()");
+        final WindowContainer wc = WindowContainer.fromBinder(token.asBinder());
+        if (wc == null) {
+            throw new RuntimeException("Invalid token in screenshot transaction");
+        }
+
+        final Rect bounds = new Rect();
+        wc.getBounds(bounds);
+        bounds.offsetTo(0, 0);
+        SurfaceControl.ScreenshotGraphicBuffer buffer = SurfaceControl.captureLayers(
+                wc.getSurfaceControl(), bounds, 1);
+
+        if (buffer == null || buffer.getGraphicBuffer() == null) {
+            return false;
+        }
+
+        SurfaceControl screenshot = mService.mWindowManager.mSurfaceControlFactory.apply(null)
+                .setName(wc.getName() + " - Organizer Screenshot")
+                .setBufferSize(bounds.width(), bounds.height())
+                .setFormat(PixelFormat.TRANSLUCENT)
+                .setParent(wc.getParentSurfaceControl())
+                .build();
+
+        Surface surface = new Surface();
+        surface.copyFrom(screenshot);
+        surface.attachAndQueueBufferWithColorSpace(buffer.getGraphicBuffer(), null);
+        surface.release();
+
+        outSurfaceControl.copyFrom(screenshot);
+        return true;
+    }
+
     private void enforceStackPermission(String func) {
         mService.mAmInternal.enforceCallingPermission(MANAGE_ACTIVITY_STACKS, func);
     }