Android4.0 状态栏添加截屏功能按钮

1>frameworks\base\packages\SystemUI\res\layout-sw600dp\status_bar.xml：添加

<com.android.systemui.statusbar.policy.KeyButtonView 
            android:id="@+id/sysbar_screenshot"
            android:layout_width="80dip"
            android:layout_height="match_parent"
            android:src="@drawable/ic_sysbar_screenshot" //搞个摄像头模样的图片放在frameworks\base\packages\SystemUI\res\drawable-mdpi
            systemui:glowBackground="@drawable/ic_sysbar_highlight" />

2>frameworks\base\packages\SystemUI\src\com\android\systemui\statusbar\tablet\TabletStatusBar.java：添加

import android.content.ServiceConnection; import android.content.ComponentName; import android.os.Messenger; import android.util.Log; import android.os.ServiceManager; View mPrintScreenButton;//cao protected View makeStatusBarView() { 。。。。。。。 mPrintScreenButton = mNavigationArea.findViewById(R.id.sysbar_screenshot); mPrintScreenButton.setOnClickListener(mOnClickListener); 。。。。。。。 ｝ private void setNavigationVisibility(int visibility) { 。。。。。。。 mPrintScreenButton.setVisibility(View.VISIBLE); ｝ private View.OnClickListener mOnClickListener = new View.OnClickListener() { 。。。。。。。 else if(v == mPrintScreenButton){             new Thread(new Runnable() {                       @Override                       public void run() {                           takeScreenshot();                       }                   }).start();                         } ｝

另外加上以下代码（截屏功能属于Android4.0自带功能，以下代码在frameworks\base\policy\src\com\android\internal\policy\impl\PhoneWindowManager.java可找到）。

private void takeScreenshot() {    synchronized (mScreenshotLock) {                   if (mScreenshotConnection != null) {                         return;                     }                 ComponentName cn = new ComponentName("com.android.systemui", "com.android.systemui.screenshot.TakeScreenshotService");                 Intent intent = new Intent();                 intent.setComponent(cn);                ServiceConnection conn = new ServiceConnection() {                         @Override                             public void onServiceConnected(ComponentName name, IBinder service) {                                 synchronized (mScreenshotLock) {                                         if (mScreenshotConnection != this) {                                                 return;                                             }                                         Messenger messenger = new Messenger(service);                                        Message msg = Message.obtain(null, 1);                                         final ServiceConnection myConn = this;                                        Handler h = new Handler(mHandler.getLooper()) {                                                 @Override                                                     public void handleMessage(Message msg) {                                                        synchronized (mScreenshotLock) {                                                                 if (mScreenshotConnection == myConn) {                                                                         mContext.unbindService(mScreenshotConnection);                                                                         mScreenshotConnection = null;                                                                         mHandler.removeCallbacks(mScreenshotTimeout);                                                                    }                                                             }                                                    }                                            };                                         msg.replyTo = new Messenger(h);                                         msg.arg1 = msg.arg2 = 0;                                         //if (mStatusBar != null && mStatusBar.isVisibleLw())                                                 // msg.arg1 = 1;                                        //if (mNavigationBar != null && mNavigationBar.isVisibleLw())                                                 //msg.arg2 = 1;                                         try {                                                 messenger.send(msg);                                             } catch (RemoteException e) {                                            }                                    }                             }                         @Override                             public void onServiceDisconnected(ComponentName name) {}                     };                 if (mContext.bindService(intent, conn, Context.BIND_AUTO_CREATE)) {                         mScreenshotConnection = conn;                         mHandler.postDelayed(mScreenshotTimeout, 10000);                     }            }       } private final Runnable mScreenshotChordLongPress = new Runnable() {            public void run() {                     takeScreenshot();                 }        }; final Object mScreenshotLock = new Object();     ServiceConnection mScreenshotConnection = null; final Runnable mScreenshotTimeout = new Runnable() {             @Override public void run() {                     synchronized (mScreenshotLock) {                            if (mScreenshotConnection != null) {                                     mContext.unbindService(mScreenshotConnection);                                     mScreenshotConnection = null;                                }                         }                }        };