文件：
frameworks/base/core/java/android/provider/Setings.java
public static final String END_BUTTON_BEHAVIOR = "end_button_behavior";
/**
* END_BUTTON_BEHAVIOR value for "go home".
* @hide
*/
public static final int END_BUTTON_BEHAVIOR_HOME = 0x1;
/**
* END_BUTTON_BEHAVIOR value for "go to sleep".
* @hide
*/
public static final int END_BUTTON_BEHAVIOR_SLEEP = 0x2;
/**
* END_BUTTON_BEHAVIOR default value.
* @hide
*/
public static final int END_BUTTON_BEHAVIOR_DEFAULT = END_BUTTON_BEHAVIOR_SLEEP;
另：关于getInt(ContentResolver cr, String name, int def)接口参数的问题，最后一个参数def是默认值，在没有读取到数据库中的设置数据时使用，在文件：frameworks/base/policy/src/com/android/internal/policy/impl/PhoneWindowManager.java中有语句：mEndcallBehavior = Settings.System.getInt(resolver,
Settings.System.END_BUTTON_BEHAVIOR,
Settings.System.END_BUTTON_BEHAVIOR_DEFAULT);用来获取挂断键的默认行为以供在下面挂断键消息来了之后做处理：
case KeyEvent.KEYCODE_ENDCALL: {
result &= ~ACTION_PASS_TO_USER;
if (down) {
ITelephony telephonyService = getTelephonyService();
boolean hungUp = false;
if (telephonyService != null) {
try {
hungUp = telephonyService.endCall();
} catch (RemoteException ex) {
Log.w(TAG, "ITelephony threw RemoteException", ex);
}
}
interceptPowerKeyDown(!isScreenOn || hungUp);
} else {
if (interceptPowerKeyUp(canceled)) {
if ((mEndcallBehavior
& Settings.System.END_BUTTON_BEHAVIOR_HOME) != 0) {
if (goHome()) {
break;
}
}
if ((mEndcallBehavior
& Settings.System.END_BUTTON_BEHAVIOR_SLEEP) != 0) {
result = (result & ~ACTION_POKE_USER_ACTIVITY) | ACTION_GO_TO_SLEEP;
}
}
}
break;
