如何从messenger chat head服务等服务中检测后退按钮/主页按下？

public class MyBroadcastReceiver extends BroadcastReceiver {
    @Override
    public void onReceive(Context context, Intent intent) {
        String action = intent.getAction();
        if (action != null) {
            if (action.equals(Intent.ACTION_CLOSE_SYSTEM_DIALOGS)) {
                String reason = intent.getStringExtra("reason");
                if (reason != null && reason.equals("homekey")) {
                    // 处理主页按下事件
                    // 关闭chat head服务或执行其他自定义操作
                } else if (reason != null && reason.equals("recentapps")) {
                    // 处理多任务视图按下事件
                    // 关闭chat head服务或执行其他自定义操作
                }
            } else if (action.equals(Intent.ACTION_SCREEN_OFF)) {
                // 处理屏幕关闭事件
                // 关闭chat head服务或执行其他自定义操作
            }
        }
    }
}

IntentFilter filter = new IntentFilter();
filter.addAction(Intent.ACTION_CLOSE_SYSTEM_DIALOGS);
filter.addAction(Intent.ACTION_SCREEN_OFF);
context.registerReceiver(new MyBroadcastReceiver(), filter);