/* * Copyright (C) 2009 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.accessibilityservice; import android.accessibilityservice.GestureDescription.MotionEventGenerator; import android.annotation.IntDef; import android.annotation.NonNull; import android.annotation.Nullable; import android.app.Service; import android.content.Context; import android.content.Intent; import android.content.pm.ParceledListSlice; import android.graphics.Region; import android.os.Handler; import android.os.IBinder; import android.os.Looper; import android.os.Message; import android.os.RemoteException; import android.provider.Settings; import android.util.ArrayMap; import android.util.Log; import android.util.Pair; import android.util.Slog; import android.util.SparseArray; import android.view.KeyEvent; import android.view.MotionEvent; import android.view.WindowManager; import android.view.WindowManagerImpl; import android.view.accessibility.AccessibilityEvent; import android.view.accessibility.AccessibilityInteractionClient; import android.view.accessibility.AccessibilityNodeInfo; import android.view.accessibility.AccessibilityWindowInfo; import com.android.internal.os.HandlerCaller; import com.android.internal.os.SomeArgs; import java.lang.annotation.Retention; import java.lang.annotation.RetentionPolicy; import java.util.List; /** * Accessibility services should only be used to assist users with disabilities in using * Android devices and apps. They run in the background and receive callbacks by the system * when {@link AccessibilityEvent}s are fired. Such events denote some state transition * in the user interface, for example, the focus has changed, a button has been clicked, * etc. Such a service can optionally request the capability for querying the content * of the active window. Development of an accessibility service requires extending this * class and implementing its abstract methods. * *
*

Developer Guides

*

For more information about creating AccessibilityServices, read the * Accessibility * developer guide.

*
* *

Lifecycle

*

* The lifecycle of an accessibility service is managed exclusively by the system and * follows the established service life cycle. Starting an accessibility service is triggered * exclusively by the user explicitly turning the service on in device settings. After the system * binds to a service, it calls {@link AccessibilityService#onServiceConnected()}. This method can * be overriden by clients that want to perform post binding setup. *

*

* An accessibility service stops either when the user turns it off in device settings or when * it calls {@link AccessibilityService#disableSelf()}. *

*

Declaration

*

* An accessibility is declared as any other service in an AndroidManifest.xml, but it * must do two things: *

* If either of these items is missing, the system will ignore the accessibility service. * Following is an example declaration: *

*
 <service android:name=".MyAccessibilityService"
 *         android:permission="android.permission.BIND_ACCESSIBILITY_SERVICE">
 *     <intent-filter>
 *         <action android:name="android.accessibilityservice.AccessibilityService" />
 *     </intent-filter>
 *     . . .
 * </service>
*

Configuration

*

* An accessibility service can be configured to receive specific types of accessibility events, * listen only to specific packages, get events from each type only once in a given time frame, * retrieve window content, specify a settings activity, etc. *

*

* There are two approaches for configuring an accessibility service: *

* *

Retrieving window content

*

* A service can specify in its declaration that it can retrieve window * content which is represented as a tree of {@link AccessibilityWindowInfo} and * {@link AccessibilityNodeInfo} objects. Note that * declaring this capability requires that the service declares its configuration via * an XML resource referenced by {@link #SERVICE_META_DATA}. *

*

* Window content may be retrieved with * {@link AccessibilityEvent#getSource() AccessibilityEvent.getSource()}, * {@link AccessibilityService#findFocus(int)}, * {@link AccessibilityService#getWindows()}, or * {@link AccessibilityService#getRootInActiveWindow()}. *

*

* Note An accessibility service may have requested to be notified for * a subset of the event types, and thus be unaware when the node hierarchy has changed. It is also * possible for a node to contain outdated information because the window content may change at any * time. *

*

Notification strategy

*

* All accessibility services are notified of all events they have requested, regardless of their * feedback type. *

*

* Note: The event notification timeout is useful to avoid propagating * events to the client too frequently since this is accomplished via an expensive * interprocess call. One can think of the timeout as a criteria to determine when * event generation has settled down.

*

Event types

* *

Feedback types

* * @see AccessibilityEvent * @see AccessibilityServiceInfo * @see android.view.accessibility.AccessibilityManager */ public abstract class AccessibilityService extends Service { /** * The user has performed a swipe up gesture on the touch screen. */ public static final int GESTURE_SWIPE_UP = 1; /** * The user has performed a swipe down gesture on the touch screen. */ public static final int GESTURE_SWIPE_DOWN = 2; /** * The user has performed a swipe left gesture on the touch screen. */ public static final int GESTURE_SWIPE_LEFT = 3; /** * The user has performed a swipe right gesture on the touch screen. */ public static final int GESTURE_SWIPE_RIGHT = 4; /** * The user has performed a swipe left and right gesture on the touch screen. */ public static final int GESTURE_SWIPE_LEFT_AND_RIGHT = 5; /** * The user has performed a swipe right and left gesture on the touch screen. */ public static final int GESTURE_SWIPE_RIGHT_AND_LEFT = 6; /** * The user has performed a swipe up and down gesture on the touch screen. */ public static final int GESTURE_SWIPE_UP_AND_DOWN = 7; /** * The user has performed a swipe down and up gesture on the touch screen. */ public static final int GESTURE_SWIPE_DOWN_AND_UP = 8; /** * The user has performed a left and up gesture on the touch screen. */ public static final int GESTURE_SWIPE_LEFT_AND_UP = 9; /** * The user has performed a left and down gesture on the touch screen. */ public static final int GESTURE_SWIPE_LEFT_AND_DOWN = 10; /** * The user has performed a right and up gesture on the touch screen. */ public static final int GESTURE_SWIPE_RIGHT_AND_UP = 11; /** * The user has performed a right and down gesture on the touch screen. */ public static final int GESTURE_SWIPE_RIGHT_AND_DOWN = 12; /** * The user has performed an up and left gesture on the touch screen. */ public static final int GESTURE_SWIPE_UP_AND_LEFT = 13; /** * The user has performed an up and right gesture on the touch screen. */ public static final int GESTURE_SWIPE_UP_AND_RIGHT = 14; /** * The user has performed an down and left gesture on the touch screen. */ public static final int GESTURE_SWIPE_DOWN_AND_LEFT = 15; /** * The user has performed an down and right gesture on the touch screen. */ public static final int GESTURE_SWIPE_DOWN_AND_RIGHT = 16; /** * The {@link Intent} that must be declared as handled by the service. */ public static final String SERVICE_INTERFACE = "android.accessibilityservice.AccessibilityService"; /** * Name under which an AccessibilityService component publishes information * about itself. This meta-data must reference an XML resource containing an * <{@link android.R.styleable#AccessibilityService accessibility-service}> * tag. This is a a sample XML file configuring an accessibility service: *
 <accessibility-service
     *     android:accessibilityEventTypes="typeViewClicked|typeViewFocused"
     *     android:packageNames="foo.bar, foo.baz"
     *     android:accessibilityFeedbackType="feedbackSpoken"
     *     android:notificationTimeout="100"
     *     android:accessibilityFlags="flagDefault"
     *     android:settingsActivity="foo.bar.TestBackActivity"
     *     android:canRetrieveWindowContent="true"
     *     android:canRequestTouchExplorationMode="true"
     *     . . .
     * />
*/ public static final String SERVICE_META_DATA = "android.accessibilityservice"; /** * Action to go back. */ public static final int GLOBAL_ACTION_BACK = 1; /** * Action to go home. */ public static final int GLOBAL_ACTION_HOME = 2; /** * Action to toggle showing the overview of recent apps */ public static final int GLOBAL_ACTION_RECENTS = 3; /** * Action to open the notifications. */ public static final int GLOBAL_ACTION_NOTIFICATIONS = 4; /** * Action to open the quick settings. */ public static final int GLOBAL_ACTION_QUICK_SETTINGS = 5; /** * Action to open the power long-press dialog. */ public static final int GLOBAL_ACTION_POWER_DIALOG = 6; /** * Action to toggle docking the current app's window */ public static final int GLOBAL_ACTION_TOGGLE_SPLIT_SCREEN = 7; private static final String LOG_TAG = "AccessibilityService"; /** * @hide */ public interface Callbacks { public void onAccessibilityEvent(AccessibilityEvent event); public void onInterrupt(); public void onServiceConnected(); public void init(int connectionId, IBinder windowToken); public boolean onGesture(int gestureId); public boolean onKeyEvent(KeyEvent event); public void onMagnificationChanged(@NonNull Region region, float scale, float centerX, float centerY); public void onSoftKeyboardShowModeChanged(int showMode); public void onPerformGestureResult(int sequence, boolean completedSuccessfully); } /** * Annotations for Soft Keyboard show modes so tools can catch invalid show modes. * @hide */ @Retention(RetentionPolicy.SOURCE) @IntDef({SHOW_MODE_AUTO, SHOW_MODE_HIDDEN}) public @interface SoftKeyboardShowMode {}; public static final int SHOW_MODE_AUTO = 0; public static final int SHOW_MODE_HIDDEN = 1; private int mConnectionId; private AccessibilityServiceInfo mInfo; private IBinder mWindowToken; private WindowManager mWindowManager; private MagnificationController mMagnificationController; private SoftKeyboardController mSoftKeyboardController; private int mGestureStatusCallbackSequence; private SparseArray mGestureStatusCallbackInfos; private final Object mLock = new Object(); /** * Callback for {@link android.view.accessibility.AccessibilityEvent}s. * * @param event The new event. This event is owned by the caller and cannot be used after * this method returns. Services wishing to use the event after this method returns should * make a copy. */ public abstract void onAccessibilityEvent(AccessibilityEvent event); /** * Callback for interrupting the accessibility feedback. */ public abstract void onInterrupt(); /** * Dispatches service connection to internal components first, then the * client code. */ private void dispatchServiceConnected() { if (mMagnificationController != null) { mMagnificationController.onServiceConnected(); } // The client gets to handle service connection last, after we've set // up any state upon which their code may rely. onServiceConnected(); } /** * This method is a part of the {@link AccessibilityService} lifecycle and is * called after the system has successfully bound to the service. If is * convenient to use this method for setting the {@link AccessibilityServiceInfo}. * * @see AccessibilityServiceInfo * @see #setServiceInfo(AccessibilityServiceInfo) */ protected void onServiceConnected() { } /** * Called by the system when the user performs a specific gesture on the * touch screen. * * Note: To receive gestures an accessibility service must * request that the device is in touch exploration mode by setting the * {@link android.accessibilityservice.AccessibilityServiceInfo#FLAG_REQUEST_TOUCH_EXPLORATION_MODE} * flag. * * @param gestureId The unique id of the performed gesture. * * @return Whether the gesture was handled. * * @see #GESTURE_SWIPE_UP * @see #GESTURE_SWIPE_UP_AND_LEFT * @see #GESTURE_SWIPE_UP_AND_DOWN * @see #GESTURE_SWIPE_UP_AND_RIGHT * @see #GESTURE_SWIPE_DOWN * @see #GESTURE_SWIPE_DOWN_AND_LEFT * @see #GESTURE_SWIPE_DOWN_AND_UP * @see #GESTURE_SWIPE_DOWN_AND_RIGHT * @see #GESTURE_SWIPE_LEFT * @see #GESTURE_SWIPE_LEFT_AND_UP * @see #GESTURE_SWIPE_LEFT_AND_RIGHT * @see #GESTURE_SWIPE_LEFT_AND_DOWN * @see #GESTURE_SWIPE_RIGHT * @see #GESTURE_SWIPE_RIGHT_AND_UP * @see #GESTURE_SWIPE_RIGHT_AND_LEFT * @see #GESTURE_SWIPE_RIGHT_AND_DOWN */ protected boolean onGesture(int gestureId) { return false; } /** * Callback that allows an accessibility service to observe the key events * before they are passed to the rest of the system. This means that the events * are first delivered here before they are passed to the device policy, the * input method, or applications. *

* Note: It is important that key events are handled in such * a way that the event stream that would be passed to the rest of the system * is well-formed. For example, handling the down event but not the up event * and vice versa would generate an inconsistent event stream. *

*

* Note: The key events delivered in this method are copies * and modifying them will have no effect on the events that will be passed * to the system. This method is intended to perform purely filtering * functionality. *

* * @param event The event to be processed. This event is owned by the caller and cannot be used * after this method returns. Services wishing to use the event after this method returns should * make a copy. * @return If true then the event will be consumed and not delivered to * applications, otherwise it will be delivered as usual. */ protected boolean onKeyEvent(KeyEvent event) { return false; } /** * Gets the windows on the screen. This method returns only the windows * that a sighted user can interact with, as opposed to all windows. * For example, if there is a modal dialog shown and the user cannot touch * anything behind it, then only the modal window will be reported * (assuming it is the top one). For convenience the returned windows * are ordered in a descending layer order, which is the windows that * are higher in the Z-order are reported first. Since the user can always * interact with the window that has input focus by typing, the focused * window is always returned (even if covered by a modal window). *

* Note: In order to access the windows your service has * to declare the capability to retrieve window content by setting the * {@link android.R.styleable#AccessibilityService_canRetrieveWindowContent} * property in its meta-data. For details refer to {@link #SERVICE_META_DATA}. * Also the service has to opt-in to retrieve the interactive windows by * setting the {@link AccessibilityServiceInfo#FLAG_RETRIEVE_INTERACTIVE_WINDOWS} * flag. *

* * @return The windows if there are windows and the service is can retrieve * them, otherwise an empty list. */ public List getWindows() { return AccessibilityInteractionClient.getInstance().getWindows(mConnectionId); } /** * Gets the root node in the currently active window if this service * can retrieve window content. The active window is the one that the user * is currently touching or the window with input focus, if the user is not * touching any window. *

* The currently active window is defined as the window that most recently fired one * of the following events: * {@link AccessibilityEvent#TYPE_WINDOW_STATE_CHANGED}, * {@link AccessibilityEvent#TYPE_VIEW_HOVER_ENTER}, * {@link AccessibilityEvent#TYPE_VIEW_HOVER_EXIT}. * In other words, the last window shown that also has input focus. *

*

* Note: In order to access the root node your service has * to declare the capability to retrieve window content by setting the * {@link android.R.styleable#AccessibilityService_canRetrieveWindowContent} * property in its meta-data. For details refer to {@link #SERVICE_META_DATA}. *

* * @return The root node if this service can retrieve window content. */ public AccessibilityNodeInfo getRootInActiveWindow() { return AccessibilityInteractionClient.getInstance().getRootInActiveWindow(mConnectionId); } /** * Disables the service. After calling this method, the service will be disabled and settings * will show that it is turned off. */ public final void disableSelf() { final IAccessibilityServiceConnection connection = AccessibilityInteractionClient.getInstance().getConnection(mConnectionId); if (connection != null) { try { connection.disableSelf(); } catch (RemoteException re) { throw new RuntimeException(re); } } } /** * Returns the magnification controller, which may be used to query and * modify the state of display magnification. *

* Note: In order to control magnification, your service * must declare the capability by setting the * {@link android.R.styleable#AccessibilityService_canControlMagnification} * property in its meta-data. For more information, see * {@link #SERVICE_META_DATA}. * * @return the magnification controller */ @NonNull public final MagnificationController getMagnificationController() { synchronized (mLock) { if (mMagnificationController == null) { mMagnificationController = new MagnificationController(this, mLock); } return mMagnificationController; } } /** * Dispatch a gesture to the touch screen. Any gestures currently in progress, whether from * the user, this service, or another service, will be cancelled. *

* The gesture will be dispatched as if it were performed directly on the screen by a user, so * the events may be affected by features such as magnification and explore by touch. *

*

* Note: In order to dispatch gestures, your service * must declare the capability by setting the * {@link android.R.styleable#AccessibilityService_canPerformGestures} * property in its meta-data. For more information, see * {@link #SERVICE_META_DATA}. *

* * @param gesture The gesture to dispatch * @param callback The object to call back when the status of the gesture is known. If * {@code null}, no status is reported. * @param handler The handler on which to call back the {@code callback} object. If * {@code null}, the object is called back on the service's main thread. * * @return {@code true} if the gesture is dispatched, {@code false} if not. */ public final boolean dispatchGesture(@NonNull GestureDescription gesture, @Nullable GestureResultCallback callback, @Nullable Handler handler) { final IAccessibilityServiceConnection connection = AccessibilityInteractionClient.getInstance().getConnection( mConnectionId); if (connection == null) { return false; } List steps = MotionEventGenerator.getGestureStepsFromGestureDescription(gesture, 100); try { synchronized (mLock) { mGestureStatusCallbackSequence++; if (callback != null) { if (mGestureStatusCallbackInfos == null) { mGestureStatusCallbackInfos = new SparseArray<>(); } GestureResultCallbackInfo callbackInfo = new GestureResultCallbackInfo(gesture, callback, handler); mGestureStatusCallbackInfos.put(mGestureStatusCallbackSequence, callbackInfo); } connection.sendGesture(mGestureStatusCallbackSequence, new ParceledListSlice<>(steps)); } } catch (RemoteException re) { throw new RuntimeException(re); } return true; } void onPerformGestureResult(int sequence, final boolean completedSuccessfully) { if (mGestureStatusCallbackInfos == null) { return; } GestureResultCallbackInfo callbackInfo; synchronized (mLock) { callbackInfo = mGestureStatusCallbackInfos.get(sequence); } final GestureResultCallbackInfo finalCallbackInfo = callbackInfo; if ((callbackInfo != null) && (callbackInfo.gestureDescription != null) && (callbackInfo.callback != null)) { if (callbackInfo.handler != null) { callbackInfo.handler.post(new Runnable() { @Override public void run() { if (completedSuccessfully) { finalCallbackInfo.callback .onCompleted(finalCallbackInfo.gestureDescription); } else { finalCallbackInfo.callback .onCancelled(finalCallbackInfo.gestureDescription); } } }); return; } if (completedSuccessfully) { callbackInfo.callback.onCompleted(callbackInfo.gestureDescription); } else { callbackInfo.callback.onCancelled(callbackInfo.gestureDescription); } } } private void onMagnificationChanged(@NonNull Region region, float scale, float centerX, float centerY) { if (mMagnificationController != null) { mMagnificationController.dispatchMagnificationChanged( region, scale, centerX, centerY); } } /** * Used to control and query the state of display magnification. */ public static final class MagnificationController { private final AccessibilityService mService; /** * Map of listeners to their handlers. Lazily created when adding the * first magnification listener. */ private ArrayMap mListeners; private final Object mLock; MagnificationController(@NonNull AccessibilityService service, @NonNull Object lock) { mService = service; mLock = lock; } /** * Called when the service is connected. */ void onServiceConnected() { synchronized (mLock) { if (mListeners != null && !mListeners.isEmpty()) { setMagnificationCallbackEnabled(true); } } } /** * Adds the specified change listener to the list of magnification * change listeners. The callback will occur on the service's main * thread. * * @param listener the listener to add, must be non-{@code null} */ public void addListener(@NonNull OnMagnificationChangedListener listener) { addListener(listener, null); } /** * Adds the specified change listener to the list of magnification * change listeners. The callback will occur on the specified * {@link Handler}'s thread, or on the service's main thread if the * handler is {@code null}. * * @param listener the listener to add, must be non-null * @param handler the handler on which the callback should execute, or * {@code null} to execute on the service's main thread */ public void addListener(@NonNull OnMagnificationChangedListener listener, @Nullable Handler handler) { synchronized (mLock) { if (mListeners == null) { mListeners = new ArrayMap<>(); } final boolean shouldEnableCallback = mListeners.isEmpty(); mListeners.put(listener, handler); if (shouldEnableCallback) { // This may fail if the service is not connected yet, but if we // still have listeners when it connects then we can try again. setMagnificationCallbackEnabled(true); } } } /** * Removes all instances of the specified change listener from the list * of magnification change listeners. * * @param listener the listener to remove, must be non-null * @return {@code true} if at least one instance of the listener was * removed */ public boolean removeListener(@NonNull OnMagnificationChangedListener listener) { if (mListeners == null) { return false; } synchronized (mLock) { final int keyIndex = mListeners.indexOfKey(listener); final boolean hasKey = keyIndex >= 0; if (hasKey) { mListeners.removeAt(keyIndex); } if (hasKey && mListeners.isEmpty()) { // We just removed the last listener, so we don't need // callbacks from the service anymore. setMagnificationCallbackEnabled(false); } return hasKey; } } private void setMagnificationCallbackEnabled(boolean enabled) { final IAccessibilityServiceConnection connection = AccessibilityInteractionClient.getInstance().getConnection( mService.mConnectionId); if (connection != null) { try { connection.setMagnificationCallbackEnabled(enabled); } catch (RemoteException re) { throw new RuntimeException(re); } } } /** * Dispatches magnification changes to any registered listeners. This * should be called on the service's main thread. */ void dispatchMagnificationChanged(final @NonNull Region region, final float scale, final float centerX, final float centerY) { final ArrayMap entries; synchronized (mLock) { if (mListeners == null || mListeners.isEmpty()) { Slog.d(LOG_TAG, "Received magnification changed " + "callback with no listeners registered!"); setMagnificationCallbackEnabled(false); return; } // Listeners may remove themselves. Perform a shallow copy to avoid concurrent // modification. entries = new ArrayMap<>(mListeners); } for (int i = 0, count = entries.size(); i < count; i++) { final OnMagnificationChangedListener listener = entries.keyAt(i); final Handler handler = entries.valueAt(i); if (handler != null) { handler.post(new Runnable() { @Override public void run() { listener.onMagnificationChanged(MagnificationController.this, region, scale, centerX, centerY); } }); } else { // We're already on the main thread, just run the listener. listener.onMagnificationChanged(this, region, scale, centerX, centerY); } } } /** * Returns the current magnification scale. *

* Note: If the service is not yet connected (e.g. * {@link AccessibilityService#onServiceConnected()} has not yet been * called) or the service has been disconnected, this method will * return a default value of {@code 1.0f}. * * @return the current magnification scale */ public float getScale() { final IAccessibilityServiceConnection connection = AccessibilityInteractionClient.getInstance().getConnection( mService.mConnectionId); if (connection != null) { try { return connection.getMagnificationScale(); } catch (RemoteException re) { Log.w(LOG_TAG, "Failed to obtain scale", re); re.rethrowFromSystemServer(); } } return 1.0f; } /** * Returns the unscaled screen-relative X coordinate of the focal * center of the magnified region. This is the point around which * zooming occurs and is guaranteed to lie within the magnified * region. *

* Note: If the service is not yet connected (e.g. * {@link AccessibilityService#onServiceConnected()} has not yet been * called) or the service has been disconnected, this method will * return a default value of {@code 0.0f}. * * @return the unscaled screen-relative X coordinate of the center of * the magnified region */ public float getCenterX() { final IAccessibilityServiceConnection connection = AccessibilityInteractionClient.getInstance().getConnection( mService.mConnectionId); if (connection != null) { try { return connection.getMagnificationCenterX(); } catch (RemoteException re) { Log.w(LOG_TAG, "Failed to obtain center X", re); re.rethrowFromSystemServer(); } } return 0.0f; } /** * Returns the unscaled screen-relative Y coordinate of the focal * center of the magnified region. This is the point around which * zooming occurs and is guaranteed to lie within the magnified * region. *

* Note: If the service is not yet connected (e.g. * {@link AccessibilityService#onServiceConnected()} has not yet been * called) or the service has been disconnected, this method will * return a default value of {@code 0.0f}. * * @return the unscaled screen-relative Y coordinate of the center of * the magnified region */ public float getCenterY() { final IAccessibilityServiceConnection connection = AccessibilityInteractionClient.getInstance().getConnection( mService.mConnectionId); if (connection != null) { try { return connection.getMagnificationCenterY(); } catch (RemoteException re) { Log.w(LOG_TAG, "Failed to obtain center Y", re); re.rethrowFromSystemServer(); } } return 0.0f; } /** * Returns the region of the screen currently active for magnification. Changes to * magnification scale and center only affect this portion of the screen. The rest of the * screen, for example input methods, cannot be magnified. This region is relative to the * unscaled screen and is independent of the scale and center point. *

* The returned region will be empty if magnification is not active. Magnification is active * if magnification gestures are enabled or if a service is running that can control * magnification. *

* Note: If the service is not yet connected (e.g. * {@link AccessibilityService#onServiceConnected()} has not yet been * called) or the service has been disconnected, this method will * return an empty region. * * @return the region of the screen currently active for magnification, or an empty region * if magnification is not active. */ @NonNull public Region getMagnificationRegion() { final IAccessibilityServiceConnection connection = AccessibilityInteractionClient.getInstance().getConnection( mService.mConnectionId); if (connection != null) { try { return connection.getMagnificationRegion(); } catch (RemoteException re) { Log.w(LOG_TAG, "Failed to obtain magnified region", re); re.rethrowFromSystemServer(); } } return Region.obtain(); } /** * Resets magnification scale and center to their default (e.g. no * magnification) values. *

* Note: If the service is not yet connected (e.g. * {@link AccessibilityService#onServiceConnected()} has not yet been * called) or the service has been disconnected, this method will have * no effect and return {@code false}. * * @param animate {@code true} to animate from the current scale and * center or {@code false} to reset the scale and center * immediately * @return {@code true} on success, {@code false} on failure */ public boolean reset(boolean animate) { final IAccessibilityServiceConnection connection = AccessibilityInteractionClient.getInstance().getConnection( mService.mConnectionId); if (connection != null) { try { return connection.resetMagnification(animate); } catch (RemoteException re) { Log.w(LOG_TAG, "Failed to reset", re); re.rethrowFromSystemServer(); } } return false; } /** * Sets the magnification scale. *

* Note: If the service is not yet connected (e.g. * {@link AccessibilityService#onServiceConnected()} has not yet been * called) or the service has been disconnected, this method will have * no effect and return {@code false}. * * @param scale the magnification scale to set, must be >= 1 and <= 5 * @param animate {@code true} to animate from the current scale or * {@code false} to set the scale immediately * @return {@code true} on success, {@code false} on failure */ public boolean setScale(float scale, boolean animate) { final IAccessibilityServiceConnection connection = AccessibilityInteractionClient.getInstance().getConnection( mService.mConnectionId); if (connection != null) { try { return connection.setMagnificationScaleAndCenter( scale, Float.NaN, Float.NaN, animate); } catch (RemoteException re) { Log.w(LOG_TAG, "Failed to set scale", re); re.rethrowFromSystemServer(); } } return false; } /** * Sets the center of the magnified viewport. *

* Note: If the service is not yet connected (e.g. * {@link AccessibilityService#onServiceConnected()} has not yet been * called) or the service has been disconnected, this method will have * no effect and return {@code false}. * * @param centerX the unscaled screen-relative X coordinate on which to * center the viewport * @param centerY the unscaled screen-relative Y coordinate on which to * center the viewport * @param animate {@code true} to animate from the current viewport * center or {@code false} to set the center immediately * @return {@code true} on success, {@code false} on failure */ public boolean setCenter(float centerX, float centerY, boolean animate) { final IAccessibilityServiceConnection connection = AccessibilityInteractionClient.getInstance().getConnection( mService.mConnectionId); if (connection != null) { try { return connection.setMagnificationScaleAndCenter( Float.NaN, centerX, centerY, animate); } catch (RemoteException re) { Log.w(LOG_TAG, "Failed to set center", re); re.rethrowFromSystemServer(); } } return false; } /** * Listener for changes in the state of magnification. */ public interface OnMagnificationChangedListener { /** * Called when the magnified region, scale, or center changes. * * @param controller the magnification controller * @param region the magnification region * @param scale the new scale * @param centerX the new X coordinate, in unscaled coordinates, around which * magnification is focused * @param centerY the new Y coordinate, in unscaled coordinates, around which * magnification is focused */ void onMagnificationChanged(@NonNull MagnificationController controller, @NonNull Region region, float scale, float centerX, float centerY); } } /** * Returns the soft keyboard controller, which may be used to query and modify the soft keyboard * show mode. * * @return the soft keyboard controller */ @NonNull public final SoftKeyboardController getSoftKeyboardController() { synchronized (mLock) { if (mSoftKeyboardController == null) { mSoftKeyboardController = new SoftKeyboardController(this, mLock); } return mSoftKeyboardController; } } private void onSoftKeyboardShowModeChanged(int showMode) { if (mSoftKeyboardController != null) { mSoftKeyboardController.dispatchSoftKeyboardShowModeChanged(showMode); } } /** * Used to control and query the soft keyboard show mode. */ public static final class SoftKeyboardController { private final AccessibilityService mService; /** * Map of listeners to their handlers. Lazily created when adding the first * soft keyboard change listener. */ private ArrayMap mListeners; private final Object mLock; SoftKeyboardController(@NonNull AccessibilityService service, @NonNull Object lock) { mService = service; mLock = lock; } /** * Called when the service is connected. */ void onServiceConnected() { synchronized(mLock) { if (mListeners != null && !mListeners.isEmpty()) { setSoftKeyboardCallbackEnabled(true); } } } /** * Adds the specified change listener to the list of show mode change listeners. The * callback will occur on the service's main thread. Listener is not called on registration. */ public void addOnShowModeChangedListener(@NonNull OnShowModeChangedListener listener) { addOnShowModeChangedListener(listener, null); } /** * Adds the specified change listener to the list of soft keyboard show mode change * listeners. The callback will occur on the specified {@link Handler}'s thread, or on the * services's main thread if the handler is {@code null}. * * @param listener the listener to add, must be non-null * @param handler the handler on which to callback should execute, or {@code null} to * execute on the service's main thread */ public void addOnShowModeChangedListener(@NonNull OnShowModeChangedListener listener, @Nullable Handler handler) { synchronized (mLock) { if (mListeners == null) { mListeners = new ArrayMap<>(); } final boolean shouldEnableCallback = mListeners.isEmpty(); mListeners.put(listener, handler); if (shouldEnableCallback) { // This may fail if the service is not connected yet, but if we still have // listeners when it connects, we can try again. setSoftKeyboardCallbackEnabled(true); } } } /** * Removes all instances of the specified change listener from the list of magnification * change listeners. * * @param listener the listener to remove, must be non-null * @return {@code true} if at least one instance of the listener was removed */ public boolean removeOnShowModeChangedListener(@NonNull OnShowModeChangedListener listener) { if (mListeners == null) { return false; } synchronized (mLock) { final int keyIndex = mListeners.indexOfKey(listener); final boolean hasKey = keyIndex >= 0; if (hasKey) { mListeners.removeAt(keyIndex); } if (hasKey && mListeners.isEmpty()) { // We just removed the last listener, so we don't need callbacks from the // service anymore. setSoftKeyboardCallbackEnabled(false); } return hasKey; } } private void setSoftKeyboardCallbackEnabled(boolean enabled) { final IAccessibilityServiceConnection connection = AccessibilityInteractionClient.getInstance().getConnection( mService.mConnectionId); if (connection != null) { try { connection.setSoftKeyboardCallbackEnabled(enabled); } catch (RemoteException re) { throw new RuntimeException(re); } } } /** * Dispatches the soft keyboard show mode change to any registered listeners. This should * be called on the service's main thread. */ void dispatchSoftKeyboardShowModeChanged(final int showMode) { final ArrayMap entries; synchronized (mLock) { if (mListeners == null || mListeners.isEmpty()) { Slog.d(LOG_TAG, "Received soft keyboard show mode changed callback" + " with no listeners registered!"); setSoftKeyboardCallbackEnabled(false); return; } // Listeners may remove themselves. Perform a shallow copy to avoid concurrent // modification. entries = new ArrayMap<>(mListeners); } for (int i = 0, count = entries.size(); i < count; i++) { final OnShowModeChangedListener listener = entries.keyAt(i); final Handler handler = entries.valueAt(i); if (handler != null) { handler.post(new Runnable() { @Override public void run() { listener.onShowModeChanged(SoftKeyboardController.this, showMode); } }); } else { // We're already on the main thread, just run the listener. listener.onShowModeChanged(this, showMode); } } } /** * Returns the show mode of the soft keyboard. The default show mode is * {@code SHOW_MODE_AUTO}, where the soft keyboard is shown when a text input field is * focused. An AccessibilityService can also request the show mode * {@code SHOW_MODE_HIDDEN}, where the soft keyboard is never shown. * * @return the current soft keyboard show mode */ @SoftKeyboardShowMode public int getShowMode() { try { return Settings.Secure.getInt(mService.getContentResolver(), Settings.Secure.ACCESSIBILITY_SOFT_KEYBOARD_MODE); } catch (Settings.SettingNotFoundException e) { Log.v(LOG_TAG, "Failed to obtain the soft keyboard mode", e); // The settings hasn't been changed yet, so it's value is null. Return the default. return 0; } } /** * Sets the soft keyboard show mode. The default show mode is * {@code SHOW_MODE_AUTO}, where the soft keyboard is shown when a text input field is * focused. An AccessibilityService can also request the show mode * {@code SHOW_MODE_HIDDEN}, where the soft keyboard is never shown. The * The lastto this method will be honored, regardless of any previous calls (including those * made by other AccessibilityServices). *

* Note: If the service is not yet conected (e.g. * {@link AccessibilityService#onServiceConnected()} has not yet been called) or the * service has been disconnected, this method will hav no effect and return {@code false}. * * @param showMode the new show mode for the soft keyboard * @return {@code true} on success */ public boolean setShowMode(@SoftKeyboardShowMode int showMode) { final IAccessibilityServiceConnection connection = AccessibilityInteractionClient.getInstance().getConnection( mService.mConnectionId); if (connection != null) { try { return connection.setSoftKeyboardShowMode(showMode); } catch (RemoteException re) { Log.w(LOG_TAG, "Failed to set soft keyboard behavior", re); re.rethrowFromSystemServer(); } } return false; } /** * Listener for changes in the soft keyboard show mode. */ public interface OnShowModeChangedListener { /** * Called when the soft keyboard behavior changes. The default show mode is * {@code SHOW_MODE_AUTO}, where the soft keyboard is shown when a text input field is * focused. An AccessibilityService can also request the show mode * {@code SHOW_MODE_HIDDEN}, where the soft keyboard is never shown. * * @param controller the soft keyboard controller * @param showMode the current soft keyboard show mode */ void onShowModeChanged(@NonNull SoftKeyboardController controller, @SoftKeyboardShowMode int showMode); } } /** * Performs a global action. Such an action can be performed * at any moment regardless of the current application or user * location in that application. For example going back, going * home, opening recents, etc. * * @param action The action to perform. * @return Whether the action was successfully performed. * * @see #GLOBAL_ACTION_BACK * @see #GLOBAL_ACTION_HOME * @see #GLOBAL_ACTION_NOTIFICATIONS * @see #GLOBAL_ACTION_RECENTS */ public final boolean performGlobalAction(int action) { IAccessibilityServiceConnection connection = AccessibilityInteractionClient.getInstance().getConnection(mConnectionId); if (connection != null) { try { return connection.performGlobalAction(action); } catch (RemoteException re) { Log.w(LOG_TAG, "Error while calling performGlobalAction", re); re.rethrowFromSystemServer(); } } return false; } /** * Find the view that has the specified focus type. The search is performed * across all windows. *

* Note: In order to access the windows your service has * to declare the capability to retrieve window content by setting the * {@link android.R.styleable#AccessibilityService_canRetrieveWindowContent} * property in its meta-data. For details refer to {@link #SERVICE_META_DATA}. * Also the service has to opt-in to retrieve the interactive windows by * setting the {@link AccessibilityServiceInfo#FLAG_RETRIEVE_INTERACTIVE_WINDOWS} * flag. Otherwise, the search will be performed only in the active window. *

* * @param focus The focus to find. One of {@link AccessibilityNodeInfo#FOCUS_INPUT} or * {@link AccessibilityNodeInfo#FOCUS_ACCESSIBILITY}. * @return The node info of the focused view or null. * * @see AccessibilityNodeInfo#FOCUS_INPUT * @see AccessibilityNodeInfo#FOCUS_ACCESSIBILITY */ public AccessibilityNodeInfo findFocus(int focus) { return AccessibilityInteractionClient.getInstance().findFocus(mConnectionId, AccessibilityNodeInfo.ANY_WINDOW_ID, AccessibilityNodeInfo.ROOT_NODE_ID, focus); } /** * Gets the an {@link AccessibilityServiceInfo} describing this * {@link AccessibilityService}. This method is useful if one wants * to change some of the dynamically configurable properties at * runtime. * * @return The accessibility service info. * * @see AccessibilityServiceInfo */ public final AccessibilityServiceInfo getServiceInfo() { IAccessibilityServiceConnection connection = AccessibilityInteractionClient.getInstance().getConnection(mConnectionId); if (connection != null) { try { return connection.getServiceInfo(); } catch (RemoteException re) { Log.w(LOG_TAG, "Error while getting AccessibilityServiceInfo", re); re.rethrowFromSystemServer(); } } return null; } /** * Sets the {@link AccessibilityServiceInfo} that describes this service. *

* Note: You can call this method any time but the info will be picked up after * the system has bound to this service and when this method is called thereafter. * * @param info The info. */ public final void setServiceInfo(AccessibilityServiceInfo info) { mInfo = info; sendServiceInfo(); } /** * Sets the {@link AccessibilityServiceInfo} for this service if the latter is * properly set and there is an {@link IAccessibilityServiceConnection} to the * AccessibilityManagerService. */ private void sendServiceInfo() { IAccessibilityServiceConnection connection = AccessibilityInteractionClient.getInstance().getConnection(mConnectionId); if (mInfo != null && connection != null) { try { connection.setServiceInfo(mInfo); mInfo = null; AccessibilityInteractionClient.getInstance().clearCache(); } catch (RemoteException re) { Log.w(LOG_TAG, "Error while setting AccessibilityServiceInfo", re); re.rethrowFromSystemServer(); } } } @Override public Object getSystemService(@ServiceName @NonNull String name) { if (getBaseContext() == null) { throw new IllegalStateException( "System services not available to Activities before onCreate()"); } // Guarantee that we always return the same window manager instance. if (WINDOW_SERVICE.equals(name)) { if (mWindowManager == null) { mWindowManager = (WindowManager) getBaseContext().getSystemService(name); } return mWindowManager; } return super.getSystemService(name); } /** * Implement to return the implementation of the internal accessibility * service interface. */ @Override public final IBinder onBind(Intent intent) { return new IAccessibilityServiceClientWrapper(this, getMainLooper(), new Callbacks() { @Override public void onServiceConnected() { AccessibilityService.this.dispatchServiceConnected(); } @Override public void onInterrupt() { AccessibilityService.this.onInterrupt(); } @Override public void onAccessibilityEvent(AccessibilityEvent event) { AccessibilityService.this.onAccessibilityEvent(event); } @Override public void init(int connectionId, IBinder windowToken) { mConnectionId = connectionId; mWindowToken = windowToken; // The client may have already obtained the window manager, so // update the default token on whatever manager we gave them. final WindowManagerImpl wm = (WindowManagerImpl) getSystemService(WINDOW_SERVICE); wm.setDefaultToken(windowToken); } @Override public boolean onGesture(int gestureId) { return AccessibilityService.this.onGesture(gestureId); } @Override public boolean onKeyEvent(KeyEvent event) { return AccessibilityService.this.onKeyEvent(event); } @Override public void onMagnificationChanged(@NonNull Region region, float scale, float centerX, float centerY) { AccessibilityService.this.onMagnificationChanged(region, scale, centerX, centerY); } @Override public void onSoftKeyboardShowModeChanged(int showMode) { AccessibilityService.this.onSoftKeyboardShowModeChanged(showMode); } @Override public void onPerformGestureResult(int sequence, boolean completedSuccessfully) { AccessibilityService.this.onPerformGestureResult(sequence, completedSuccessfully); } }); } /** * Implements the internal {@link IAccessibilityServiceClient} interface to convert * incoming calls to it back to calls on an {@link AccessibilityService}. * * @hide */ public static class IAccessibilityServiceClientWrapper extends IAccessibilityServiceClient.Stub implements HandlerCaller.Callback { private static final int DO_INIT = 1; private static final int DO_ON_INTERRUPT = 2; private static final int DO_ON_ACCESSIBILITY_EVENT = 3; private static final int DO_ON_GESTURE = 4; private static final int DO_CLEAR_ACCESSIBILITY_CACHE = 5; private static final int DO_ON_KEY_EVENT = 6; private static final int DO_ON_MAGNIFICATION_CHANGED = 7; private static final int DO_ON_SOFT_KEYBOARD_SHOW_MODE_CHANGED = 8; private static final int DO_GESTURE_COMPLETE = 9; private final HandlerCaller mCaller; private final Callbacks mCallback; private int mConnectionId; public IAccessibilityServiceClientWrapper(Context context, Looper looper, Callbacks callback) { mCallback = callback; mCaller = new HandlerCaller(context, looper, this, true /*asyncHandler*/); } public void init(IAccessibilityServiceConnection connection, int connectionId, IBinder windowToken) { Message message = mCaller.obtainMessageIOO(DO_INIT, connectionId, connection, windowToken); mCaller.sendMessage(message); } public void onInterrupt() { Message message = mCaller.obtainMessage(DO_ON_INTERRUPT); mCaller.sendMessage(message); } public void onAccessibilityEvent(AccessibilityEvent event) { Message message = mCaller.obtainMessageO(DO_ON_ACCESSIBILITY_EVENT, event); mCaller.sendMessage(message); } public void onGesture(int gestureId) { Message message = mCaller.obtainMessageI(DO_ON_GESTURE, gestureId); mCaller.sendMessage(message); } public void clearAccessibilityCache() { Message message = mCaller.obtainMessage(DO_CLEAR_ACCESSIBILITY_CACHE); mCaller.sendMessage(message); } @Override public void onKeyEvent(KeyEvent event, int sequence) { Message message = mCaller.obtainMessageIO(DO_ON_KEY_EVENT, sequence, event); mCaller.sendMessage(message); } public void onMagnificationChanged(@NonNull Region region, float scale, float centerX, float centerY) { final SomeArgs args = SomeArgs.obtain(); args.arg1 = region; args.arg2 = scale; args.arg3 = centerX; args.arg4 = centerY; final Message message = mCaller.obtainMessageO(DO_ON_MAGNIFICATION_CHANGED, args); mCaller.sendMessage(message); } public void onSoftKeyboardShowModeChanged(int showMode) { final Message message = mCaller.obtainMessageI(DO_ON_SOFT_KEYBOARD_SHOW_MODE_CHANGED, showMode); mCaller.sendMessage(message); } public void onPerformGestureResult(int sequence, boolean successfully) { Message message = mCaller.obtainMessageII(DO_GESTURE_COMPLETE, sequence, successfully ? 1 : 0); mCaller.sendMessage(message); } @Override public void executeMessage(Message message) { switch (message.what) { case DO_ON_ACCESSIBILITY_EVENT: { AccessibilityEvent event = (AccessibilityEvent) message.obj; if (event != null) { AccessibilityInteractionClient.getInstance().onAccessibilityEvent(event); mCallback.onAccessibilityEvent(event); // Make sure the event is recycled. try { event.recycle(); } catch (IllegalStateException ise) { /* ignore - best effort */ } } } return; case DO_ON_INTERRUPT: { mCallback.onInterrupt(); } return; case DO_INIT: { mConnectionId = message.arg1; SomeArgs args = (SomeArgs) message.obj; IAccessibilityServiceConnection connection = (IAccessibilityServiceConnection) args.arg1; IBinder windowToken = (IBinder) args.arg2; args.recycle(); if (connection != null) { AccessibilityInteractionClient.getInstance().addConnection(mConnectionId, connection); mCallback.init(mConnectionId, windowToken); mCallback.onServiceConnected(); } else { AccessibilityInteractionClient.getInstance().removeConnection( mConnectionId); mConnectionId = AccessibilityInteractionClient.NO_ID; AccessibilityInteractionClient.getInstance().clearCache(); mCallback.init(AccessibilityInteractionClient.NO_ID, null); } } return; case DO_ON_GESTURE: { final int gestureId = message.arg1; mCallback.onGesture(gestureId); } return; case DO_CLEAR_ACCESSIBILITY_CACHE: { AccessibilityInteractionClient.getInstance().clearCache(); } return; case DO_ON_KEY_EVENT: { KeyEvent event = (KeyEvent) message.obj; try { IAccessibilityServiceConnection connection = AccessibilityInteractionClient .getInstance().getConnection(mConnectionId); if (connection != null) { final boolean result = mCallback.onKeyEvent(event); final int sequence = message.arg1; try { connection.setOnKeyEventResult(result, sequence); } catch (RemoteException re) { /* ignore */ } } } finally { // Make sure the event is recycled. try { event.recycle(); } catch (IllegalStateException ise) { /* ignore - best effort */ } } } return; case DO_ON_MAGNIFICATION_CHANGED: { final SomeArgs args = (SomeArgs) message.obj; final Region region = (Region) args.arg1; final float scale = (float) args.arg2; final float centerX = (float) args.arg3; final float centerY = (float) args.arg4; mCallback.onMagnificationChanged(region, scale, centerX, centerY); } return; case DO_ON_SOFT_KEYBOARD_SHOW_MODE_CHANGED: { final int showMode = (int) message.arg1; mCallback.onSoftKeyboardShowModeChanged(showMode); } return; case DO_GESTURE_COMPLETE: { final boolean successfully = message.arg2 == 1; mCallback.onPerformGestureResult(message.arg1, successfully); } return; default : Log.w(LOG_TAG, "Unknown message type " + message.what); } } } /** * Class used to report status of dispatched gestures */ public static abstract class GestureResultCallback { /** Called when the gesture has completed successfully * * @param gestureDescription The description of the gesture that completed. */ public void onCompleted(GestureDescription gestureDescription) { } /** Called when the gesture was cancelled * * @param gestureDescription The description of the gesture that was cancelled. */ public void onCancelled(GestureDescription gestureDescription) { } } /* Object to keep track of gesture result callbacks */ private static class GestureResultCallbackInfo { GestureDescription gestureDescription; GestureResultCallback callback; Handler handler; GestureResultCallbackInfo(GestureDescription gestureDescription, GestureResultCallback callback, Handler handler) { this.gestureDescription = gestureDescription; this.callback = callback; this.handler = handler; } } }