實現按鍵旋轉屏幕

通過長按menu按鍵，可以旋轉屏幕方向（0°或者90°），這個功能有時蠻有用的，下面來看看是如何實現的：

1 修改按鍵處理程序
frameworks/policies/base/phone/com/android/internal/policy/impl/PhoneWindowManager.java

函數
public boolean interceptKeyTi(WindowState win, int code, int metaKeys, boolean down,
int repeatCount, int flags)
在處理菜單鍵的地方
if (code == KeyEvent.KEYCODE_MENU) {
final int chordBug = KeyEvent.META_SHIFT_ON;

            if (down && repeatCount == 0) {
if (mEnableShiftMenuBugReports && (metaKeys & chordBug) == chordBug) {
Intent intent = new Intent(Intent.ACTION_BUG_REPORT);
mContext.sendOrderedBroadcast(intent, null);
return true;
} else if (SHOW_PROCESSES_ON_ALT_MENU &&
(metaKeys & KeyEvent.META_ALT_ON) == KeyEvent.META_ALT_ON) {
Intent service = new Intent();
service.setClassName(mContext, "com.android.server.LoadAverageService");
ContentResolver res = mContext.getContentResolver();
boolean shown = Settings.System.getInt(
res, Settings.System.SHOW_PROCESSES, 0) != 0;
if (!shown) {
mContext.startService(service);
} else {
mContext.stopService(service);
}
Settings.System.putInt(
res, Settings.System.SHOW_PROCESSES, shown ? 0 : 1);
return true;
}

}
//上面是原來的內容，下面是添加的新內容
else if (down && repeatCount == 20 && MenuKeyUp && (!keyguardOn)) {
//如果按下Menu鍵一定時間，擡起時執行此段函數
MenuKeyUp = false;
try {
int ro = mWindowManager.getRotation(); //獲取當前方向

if( ro == ActivityInfo.SCREEN_ORIENTATION_LANDSCAPE ) {
ro = ActivityInfo.SCREEN_ORIENTATION_PORTRAIT;
} else {
ro = ActivityInfo.SCREEN_ORIENTATION_LANDSCAPE;
}
}
catch (RemoteException e) {
Log.v(TAG, "!!! getRotation fail !!!");
}

                try {
//旋轉屏幕
mWindowManager.setRotation(ro, true, Surface.FLAGS_ORIENTATION_ANIMATION_DISABLE);
//最後可跟不同的參數，可實現一些旋轉效果
}
catch (RemoteException e) {
Log.v(TAG, "!!! mWindowManager.setRotation fail !!!");
}
return true;
}
if(!down) {
MenuKeyUp = true;           
}
}

2 修改實現選擇的函數
/frameworks/base/services/java/com/android/server/WindowManagerService.java

找到該函數
public boolean setRotationUncheckedLocked(int rotation, int animFlags)

將以下妨礙選擇的內容註釋掉
//rotation = mPolicy.rotationForOrientationLw(mForcedAppOrientation,
//        mRotation, mDisplayEnabled);

3、當然也可以新作一個rotate鍵來選擇屏幕，以下是引用代碼

+ } else if (code == KeyEvent.KEYCODE_ROTATE) {
+ // ROTATE KEY pressed
+ if (down) {
+ mButtonPushFlg = true;
+
+ try {
+ int ro = mWindowManager.getRotation(); // Orientation vertical
+ if (ro == 3 ) {
+ mWindowManager.setRotation (Surface.ROTATION_0,true,mFancyRotationAnimation); //Orientation
landscape
+ } else {
+ mWindowManager.setRotation
(Surface.ROTATION_270,true,mFancyRotationAnimation); //Orientation
portlate
+ }
+ } catch (RemoteException e) {
+ // Igbore
+ Log.i("info", "Rotation failed ");
+ }
+ }
+ return true;
}

 

OK，重新編譯後，長按Menu鍵即可實現屏幕旋轉。