| /* |
| * 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.view.accessibility; |
| |
| import static android.util.Config.LOGV; |
| |
| import android.content.Context; |
| import android.content.pm.ServiceInfo; |
| import android.os.Binder; |
| import android.os.Handler; |
| import android.os.IBinder; |
| import android.os.Looper; |
| import android.os.Message; |
| import android.os.RemoteException; |
| import android.os.ServiceManager; |
| import android.os.SystemClock; |
| import android.util.Log; |
| |
| import java.util.Collections; |
| import java.util.List; |
| |
| /** |
| * System level service that serves as an event dispatch for {@link AccessibilityEvent}s. |
| * Such events are generated when something notable happens in the user interface, |
| * for example an {@link android.app.Activity} starts, the focus or selection of a |
| * {@link android.view.View} changes etc. Parties interested in handling accessibility |
| * events implement and register an accessibility service which extends |
| * {@link android.accessibilityservice.AccessibilityService}. |
| * |
| * @see AccessibilityEvent |
| * @see android.accessibilityservice.AccessibilityService |
| * @see android.content.Context#getSystemService |
| */ |
| public final class AccessibilityManager { |
| private static final String LOG_TAG = "AccessibilityManager"; |
| |
| static final Object sInstanceSync = new Object(); |
| |
| private static AccessibilityManager sInstance; |
| |
| private static final int DO_SET_ENABLED = 10; |
| |
| final IAccessibilityManager mService; |
| |
| final Handler mHandler; |
| |
| boolean mIsEnabled; |
| |
| final IAccessibilityManagerClient.Stub mClient = new IAccessibilityManagerClient.Stub() { |
| public void setEnabled(boolean enabled) { |
| mHandler.obtainMessage(DO_SET_ENABLED, enabled ? 1 : 0, 0).sendToTarget(); |
| } |
| }; |
| |
| class MyHandler extends Handler { |
| |
| MyHandler(Looper mainLooper) { |
| super(mainLooper); |
| } |
| |
| @Override |
| public void handleMessage(Message message) { |
| switch (message.what) { |
| case DO_SET_ENABLED : |
| synchronized (mHandler) { |
| mIsEnabled = (message.arg1 == 1); |
| } |
| return; |
| default : |
| Log.w(LOG_TAG, "Unknown message type: " + message.what); |
| } |
| } |
| } |
| |
| /** |
| * Get an AccessibilityManager instance (create one if necessary). |
| * |
| * @hide |
| */ |
| public static AccessibilityManager getInstance(Context context) { |
| synchronized (sInstanceSync) { |
| if (sInstance == null) { |
| sInstance = new AccessibilityManager(context); |
| } |
| } |
| return sInstance; |
| } |
| |
| /** |
| * Create an instance. |
| * |
| * @param context A {@link Context}. |
| */ |
| private AccessibilityManager(Context context) { |
| mHandler = new MyHandler(context.getMainLooper()); |
| IBinder iBinder = ServiceManager.getService(Context.ACCESSIBILITY_SERVICE); |
| mService = IAccessibilityManager.Stub.asInterface(iBinder); |
| try { |
| mService.addClient(mClient); |
| } catch (RemoteException re) { |
| Log.e(LOG_TAG, "AccessibilityManagerService is dead", re); |
| } |
| } |
| |
| /** |
| * Returns if the {@link AccessibilityManager} is enabled. |
| * |
| * @return True if this {@link AccessibilityManager} is enabled, false otherwise. |
| */ |
| public boolean isEnabled() { |
| synchronized (mHandler) { |
| return mIsEnabled; |
| } |
| } |
| |
| /** |
| * Sends an {@link AccessibilityEvent}. If this {@link AccessibilityManager} is not |
| * enabled the call is a NOOP. |
| * |
| * @param event The {@link AccessibilityEvent}. |
| * |
| * @throws IllegalStateException if a client tries to send an {@link AccessibilityEvent} |
| * while accessibility is not enabled. |
| */ |
| public void sendAccessibilityEvent(AccessibilityEvent event) { |
| if (!mIsEnabled) { |
| throw new IllegalStateException("Accessibility off. Did you forget to check that?"); |
| } |
| boolean doRecycle = false; |
| try { |
| event.setEventTime(SystemClock.uptimeMillis()); |
| // it is possible that this manager is in the same process as the service but |
| // client using it is called through Binder from another process. Example: MMS |
| // app adds a SMS notification and the NotificationManagerService calls this method |
| long identityToken = Binder.clearCallingIdentity(); |
| doRecycle = mService.sendAccessibilityEvent(event); |
| Binder.restoreCallingIdentity(identityToken); |
| if (LOGV) { |
| Log.i(LOG_TAG, event + " sent"); |
| } |
| } catch (RemoteException re) { |
| Log.e(LOG_TAG, "Error during sending " + event + " ", re); |
| } finally { |
| if (doRecycle) { |
| event.recycle(); |
| } |
| } |
| } |
| |
| /** |
| * Requests interruption of the accessibility feedback from all accessibility services. |
| */ |
| public void interrupt() { |
| if (!mIsEnabled) { |
| throw new IllegalStateException("Accessibility off. Did you forget to check that?"); |
| } |
| try { |
| mService.interrupt(); |
| if (LOGV) { |
| Log.i(LOG_TAG, "Requested interrupt from all services"); |
| } |
| } catch (RemoteException re) { |
| Log.e(LOG_TAG, "Error while requesting interrupt from all services. ", re); |
| } |
| } |
| |
| /** |
| * Returns the {@link ServiceInfo}s of the installed accessibility services. |
| * |
| * @return An unmodifiable list with {@link ServiceInfo}s. |
| */ |
| public List<ServiceInfo> getAccessibilityServiceList() { |
| List<ServiceInfo> services = null; |
| try { |
| services = mService.getAccessibilityServiceList(); |
| if (LOGV) { |
| Log.i(LOG_TAG, "Installed AccessibilityServices " + services); |
| } |
| } catch (RemoteException re) { |
| Log.e(LOG_TAG, "Error while obtaining the installed AccessibilityServices. ", re); |
| } |
| return Collections.unmodifiableList(services); |
| } |
| } |