Android中如何监听GPS开启和关闭

有时须要监听GPS的开关(这种需求并很少见)。实现的思路是监听表明 GPS 开关的 URI 的数据是否有发生变化

GPS的开关是系统设置，android.provider.Settings.Secure 表明了app能够读取但不能修改的系统设置。能够从这个类中获取到表明GPS开关的URI。

关键代码以下

getContentResolver()
			.registerContentObserver(
					Settings.Secure
							.getUriFor(Settings.System.LOCATION_PROVIDERS_ALLOWED),
					false, mGpsMonitor);

完整的代码以下：

public class MyActivity extends Activity {

	private final ContentObserver mGpsMonitor = new ContentObserver(null) {
		@Override
		public void onChange(boolean selfChange) {
			super.onChange(selfChange);

			boolean enabled = mLocationManager
					.isProviderEnabled(LocationManager.GPS_PROVIDER);
			System.out.println("gps enabled? " + enabled);
		}
	};

	private LocationManager mLocationManager;

	@Override
	protected void onCreate(Bundle savedInstanceState) {
		super.onCreate(savedInstanceState);
		mLocationManager = (LocationManager) getSystemService(LOCATION_SERVICE);
	}

	protected void onStart() {
		getContentResolver()
				.registerContentObserver(
						Settings.Secure
								.getUriFor(Settings.System.LOCATION_PROVIDERS_ALLOWED),
						false, mGpsMonitor);
	};

	@Override
	protected void onStop() {
		super.onStop();
		getContentResolver().unregisterContentObserver(mGpsMonitor);
	}
}