如何使用/定位在谷歌文档和服务广播文档中描述的LocalBroadcastManager ?
我试着谷歌它,但没有可用的代码开始?
文档说,我应该使用它,如果我想做广播内部与我的应用程序的进程,但我不知道在哪里寻找这个。
任何帮助/评论?
更新:我知道如何使用广播,但不知道如何在我的项目中获得LocalBroadcastManager。
如何使用/定位在谷歌文档和服务广播文档中描述的LocalBroadcastManager ?
我试着谷歌它,但没有可用的代码开始?
文档说,我应该使用它,如果我想做广播内部与我的应用程序的进程,但我不知道在哪里寻找这个。
任何帮助/评论?
更新:我知道如何使用广播,但不知道如何在我的项目中获得LocalBroadcastManager。
当前回答
接收端:
First register LocalBroadcast Receiver Then handle incoming intent data in onReceive. @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); LocalBroadcastManager lbm = LocalBroadcastManager.getInstance(this); lbm.registerReceiver(receiver, new IntentFilter("filter_string")); } public BroadcastReceiver receiver = new BroadcastReceiver() { @Override public void onReceive(Context context, Intent intent) { if (intent != null) { String str = intent.getStringExtra("key"); // get all your data from intent and do what you want } } };
发送端:
Intent intent = new Intent("filter_string");
intent.putExtra("key", "My Data");
// put your all data using put extra
LocalBroadcastManager.getInstance(this).sendBroadcast(intent);
其他回答
我还是要回答这个问题。以防有人需要。
ReceiverActivity.java
一个监视名为“custom-event-name”的事件通知的活动。
@Override
public void onCreate(Bundle savedInstanceState) {
...
// Register to receive messages.
// We are registering an observer (mMessageReceiver) to receive Intents
// with actions named "custom-event-name".
LocalBroadcastManager.getInstance(this).registerReceiver(mMessageReceiver,
new IntentFilter("custom-event-name"));
}
// Our handler for received Intents. This will be called whenever an Intent
// with an action named "custom-event-name" is broadcasted.
private BroadcastReceiver mMessageReceiver = new BroadcastReceiver() {
@Override
public void onReceive(Context context, Intent intent) {
// Get extra data included in the Intent
String message = intent.getStringExtra("message");
Log.d("receiver", "Got message: " + message);
}
};
@Override
protected void onDestroy() {
// Unregister since the activity is about to be closed.
LocalBroadcastManager.getInstance(this).unregisterReceiver(mMessageReceiver);
super.onDestroy();
}
SenderActivity.java
第二个活动发送/广播通知。
@Override
public void onCreate(Bundle savedInstanceState) {
...
// Every time a button is clicked, we want to broadcast a notification.
findViewById(R.id.button_send).setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
sendMessage();
}
});
}
// Send an Intent with an action named "custom-event-name". The Intent sent should
// be received by the ReceiverActivity.
private void sendMessage() {
Log.d("sender", "Broadcasting message");
Intent intent = new Intent("custom-event-name");
// You can also include some extra data.
intent.putExtra("message", "This is my message!");
LocalBroadcastManager.getInstance(this).sendBroadcast(intent);
}
使用上面的代码,每次按钮都是R.id。button_send被点击,Intent被广播并被ReceiverActivity中的mMessageReceiver接收。
调试输出应该是这样的:
01-16 10:35:42.413: D/sender(356): Broadcasting message
01-16 10:35:42.421: D/receiver(356): Got message: This is my message!
如何将全局广播更改为局部广播
1)创建实例
LocalBroadcastManager localBroadcastManager = LocalBroadcastManager.getInstance(this);
2)用于注册BroadcastReceiver
取代
registerReceiver(new YourReceiver(),new IntentFilter("YourAction"));
与
localBroadcastManager.registerReceiver(new YourReceiver(),new IntentFilter("YourAction"));
3)用于发送广播信息
取代
sendBroadcast(intent);
与
localBroadcastManager.sendBroadcast(intent);
4)注销广播信息
取代
unregisterReceiver(mybroadcast);
与
localBroadcastManager.unregisterReceiver(mybroadcast);
一个实现LocalBroadcastManager的Activity和Service的例子可以在开发者文档中找到。我个人觉得它非常有用。
编辑:该链接已从网站上删除,但数据如下: https://github.com/carrot-garden/android_maven-android-plugin-samples/blob/master/support4demos/src/com/example/android/supportv4/content/LocalServiceBroadcaster.java
我是一名iOS开发者,所以我做了一个类似于NotificationCenter的解决方案:
object NotificationCenter {
var observers: MutableMap<String, MutableList<NotificationObserver>> = mutableMapOf()
fun addObserver(observer: NotificationObserver, notificationName: NotificationName) {
var os = observers[notificationName.value]
if (os == null) {
os = mutableListOf<NotificationObserver>()
observers[notificationName.value] = os
}
os.add(observer)
}
fun removeObserver(observer: NotificationObserver, notificationName: NotificationName) {
val os = observers[notificationName.value]
if (os != null) {
os.remove(observer)
}
}
fun removeObserver(observer:NotificationObserver) {
observers.forEach { name, mutableList ->
if (mutableList.contains(observer)) {
mutableList.remove(observer)
}
}
}
fun postNotification(notificationName: NotificationName, obj: Any?) {
val os = observers[notificationName.value]
if (os != null) {
os.forEach {observer ->
observer.onNotification(notificationName,obj)
}
}
}
}
interface NotificationObserver {
fun onNotification(name: NotificationName,obj:Any?)
}
enum class NotificationName(val value: String) {
onPlayerStatReceived("on player stat received"),
...
}
一些想要观察通知的类必须符合观察者协议:
class MainActivity : AppCompatActivity(), NotificationObserver {
override fun onCreate(savedInstanceState: Bundle?) {
...
NotificationCenter.addObserver(this,NotificationName.onPlayerStatReceived)
}
override fun onDestroy() {
...
super.onDestroy()
NotificationCenter.removeObserver(this)
}
...
override fun onNotification(name: NotificationName, obj: Any?) {
when (name) {
NotificationName.onPlayerStatReceived -> {
Log.d(tag, "onPlayerStatReceived")
}
else -> Log.e(tag, "Notification not handled")
}
}
最后,向观察者发布一些通知:
NotificationCenter.postNotification(NotificationName.onPlayerStatReceived,null)
当你玩够了LocalBroadcastReceiver的时候,我会建议你试试Green Robot的EventBus——你一定会意识到它与LBR的区别和有用性。更少的代码,可定制关于接收者的线程(UI/Bg),检查接收者的可用性,粘性事件,事件可以用作数据传递等。