我想看一个系统设置和得到通知时，它的价值变化。在游标类有一个 setNotificationUri 方法听起来不错，但它不能正常工作和编码，也觉得很奇怪......那是我所做的：

I want to watch a system setting and get notified when its value changes. The Cursor class has a setNotificationUri method which sounded nice, but it doesn't work and coding it also feels strange... Thats what I did:

    // Create a content resolver and add a listener
    ContentResolver resolver = getContentResolver();
    resolver.addStatusChangeListener(ContentResolver.SYNC_OBSERVER_TYPE_SETTINGS | ContentResolver.SYNC_OBSERVER_TYPE_PENDING | ContentResolver.SYNC_OBSERVER_TYPE_ACTIVE, new MyObserver());

    // I somehow need to get an instance of Cursor to use setNotificationUri in the next step...
    Cursor cursor2 = resolver.query(Settings.System.CONTENT_URI, null, null, null, null);

    // For testing purposes monitor all system settings
    cursor2.setNotificationUri(resolver, Settings.System.CONTENT_URI);

监听器：

public class MyObserver implements SyncStatusObserver {

public void onStatusChanged(int which) {
    Log.d("TEST", "status changed, which = " + which);

}
}

嗯，很明显听者得到从来没有所谓，我找不到在logcat中指定的测试标签的条目）：（​​用于测试我手动更改亮度从手册中的Andr​​oid设置菜单设置为自动）。任何暗示什么，我做错了什么？任何其他更好的方法来监视Android系统设置？

Well, obviously the listener gets never called, I can't find an entry with the specified TEST tag in logcat ): (For testing I manually changed the brightness setting from manual to automatic in the android settings menu). Any hint what I am doing wrong? Any other, better way to monitor Android system settings?

感谢您的任何提示！

推荐答案

在这里是如何可以做到的，伟大工程：的如何实现一个Android ContentObserver 。注意不是某些设置先写入/当用户presses在他改变一些系统preference屏幕返回键reallly变了！

here is how it can be done, works great: How to implement an Android ContentObserver. note than some settings are first written / reallly changed when the user presses the back key in the system preference screen where he changed something!