弹出对话框的代码位于：
|
frameworks/policies/base/phone/com/android/internal/policy/impl/PhoneWindowManager.java
|
显示对话框的代码如下：
|
Runnable mPowerLongPress = new Runnable() {
public void run() {
mShouldTurnOffOnKeyUp = false;
performHapticFeedbackLw(null, HapticFeedbackConstants.LONG_PRESS, false);
sendCloseSystemWindows(SYSTEM_DIALOG_REASON_GLOBAL_ACTIONS);
showGlobalActionsDialog();
}
};
|
调用showGlobalActionsDialog方法将会显示上面提到的显示“静音”，“关机”，“重启”等选项的对话框。
继续跟踪showGlobalActionsDialog方法，代码如下：
|
void showGlobalActionsDialog() {
if (mGlobalActions == null) {
mGlobalActions = new GlobalActions(mContext);
}
final boolean keyguardShowing = mKeyguardMediator.isShowingAndNotHidden();
mGlobalActions.showDialog(keyguardShowing, isDeviceProvisioned());
if (keyguardShowing) {
// since it took two seconds of long press to bring this up,
// poke the wake lock so they have some time to see the dialog.
mKeyguardMediator.pokeWakelock();
}
}
|
GlobalActions相关的代码位于：
|
frameworks/policies/base/phone/com/android/internal/policy/impl/GlobalActions.java
|
其中，showDialog的代码如下：
|
public void showDialog(boolean keyguardShowing, boolean isDeviceProvisioned) {
mKeyguardShowing = keyguardShowing;
mDeviceProvisioned = isDeviceProvisioned;
if (mDialog == null) {
mStatusBar = (StatusBarManager)mContext.getSystemService(Context.STATUS_BAR_SERVICE);
mDialog = createDialog();
}
prepareDialog();
mStatusBar.disable(StatusBarManager.DISABLE_EXPAND);
mDialog.show();
}
|
showDialog中会调用createDialog方法，以创建相应的对话框。createDialog方法中，有如下代码：
|
mItems = Lists.newArrayList(
// silent mode
mSilentModeToggle,
// next: airplane mode
//mAirplaneModeOn,
// next: reboot
new SinglePressAction(com.android.internal.R.drawable.ic_lock_power_off, R.string.global_action_reboot){
public void onPress() {
ShutdownThread.reboot(mContext, true);
}
public boolean showDuringKeyguard() {
return true;
}
public boolean showBeforeProvisioning() {
return true;
}
},
// last: power off
new SinglePressAction(
com.android.internal.R.drawable.ic_lock_power_off,
R.string.global_action_power_off) {
public void onPress() {
// shutdown by making sure radio and power are handled accordingly.
ShutdownThread.shutdown(mContext, true);
}
public boolean showDuringKeyguard() {
return true;
}
public boolean showBeforeProvisioning() {
return true;
}
});
|
从代码中我们可以看出，如果选择上述对话框的“关机”选项之后，将会调用ShutdownThread的shutdown方法来关机，shutdown方法的第二个参数表示是否弹出询问对话框。 如果选择上述对话框的“重启”选项之后，将会调用ShutdownThread的reboot方法来重启，reboot方法的第二个参数表示是否弹出询问对话框。
createDialog方法中还有如下代码：
|
mAdapter = new MyAdapter();
final AlertDialog.Builder ab = new AlertDialog.Builder(mContext);
ab.setAdapter(mAdapter, this)
.setInverseBackgroundForced(true)
.setTitle(R.string.global_actions);
final AlertDialog dialog = ab.create();
dialog.getWindow().setType(WindowManager.LayoutParams.TYPE_SYSTEM_DIALOG);
if (!mContext.getResources().getBoolean(
com.android.internal.R.bool.config_sf_slowBlur)) {
dialog.getWindow().setFlags(WindowManager.LayoutParams.FLAG_BLUR_BEHIND,
WindowManager.LayoutParams.FLAG_BLUR_BEHIND);
}
dialog.setOnDismissListener(this);
|
其中，“dialog.getWindow().setFlags(WindowManager.LayoutParams.FLAG_BLUR_BEHIND,
WindowManager.LayoutParams.FLAG_BLUR_BEHIND);”语句的作用是添加相应的特效：即弹出对话框的时候，让对话框后面的背景模糊显示。如果不需要这样的特效，可以将相关语句注释掉即可。
其他特效：
1）FLAG_DIM_BEHIND：会让背景的亮度变暗。
再来看看ShutdownThread，其定义的源文件在：
|
frameworks/base/core/java/com/android/internal/app/ShutdownThread.java
|
如果选择上述对话框的“关机”选项之后，将会调用ShutdownThread的shutdown方法来关机。 如果选择上述对话框的“重启”选项之后，将会调用ShutdownThread的reboot方法来重启。shutdown方法和reboot方法的定义如下：
|
public static void shutdown(final Context context, boolean confirm) {
shutdown(context, confirm, false);
}
public static void reboot(final Context context, boolean confirm) {
shutdown(context, confirm, true);
}
|
它们都会调用到public static void shutdown(final Context context, boolean confirm, final boolean reboot)
