结合运行Service（后完成（））/回调处理程序 [英] binding to running Service (after finish() ) / callback Handler
问题描述
同样一个关于本地服务的问题。我如何（重新）绑定到现有服务，之后的onDestroy（）？
的问题：
我绑定到服务，并开始从活动服务。我张贴Runnable对象到活页夹，回调（更新进度）上的用户界面。当我关闭这个活动，操作系统可能结束生命周期和销毁活动，呼吁的onDestroy（），对不对？我模拟这个，调用完成（）中的onPause（）方法。所以一旦我重新启动该活动，怎么我绑定到相同的服务了吗？我认为，服务是Singelton，但是当我试图重新绑定，我得到另一种粘合剂的参考。因此， binder.callbackHandler.post（binder.progressHandler）; 仍具有参考旧粘合剂/回调/ progressHandler，不是我的新的。
连服的构造函数被再次调用！
有没有什么解决办法有一个进度条，得到更新由回调对象的服务（工作）。关闭/的onDestroy（）的活动。回来，然后继续进度？
我的code是相当大的，但重建的Szenario：
公共类的MyService延伸服务{
私人最终LocalBinder粘合剂=新LocalBinder（）;
公共类LocalBinder扩展粘合剂实现TestRunServiceBinder {
私人处理器的callbackHandler;
私人ServiceStartActivity.RunOnServiceProgress onProgress;
@覆盖
公共无效setActivityCallbackHandler（处理器的MessageHandler）{
的callbackHandler =的MessageHandler;
}
@覆盖
公共无效setServiceProgressHandler（RunOnServiceProgress可运行）{
onProgress =可运行;
}
公共无效DoSomething的（）{
_干点什么（）;
};
私人无效_doSomething（）{
而（...）{
//这样做几次（可能需要长达10分钟）
binder.callbackHandler.post（binder.progressHandler）;
等待（）
}
}
}
_
公共类ServiceStartActivity {
私人最终处理程序的MessageHandler =新的处理程序（）;
私人ServiceConnection mTestServiceConnection =新ServiceConnection（）{
@覆盖
公共无效onServiceDisconnected（组件名名）{
testRunBinder = NULL;
}
@覆盖
公共无效onServiceConnected（组件名名称，服务的IBinder）{
testRunBinder =（TestRunServiceBinder）服务;
testRunBinder.setActivityCallbackHandler（MessageHandler的）;
testRunBinder.setServiceProgressHandler（新RunOnServiceProgress（））;
}
};
@覆盖
保护无效的OnStart（）{
super.onStart（）;
//绑定到服务
最终意图serviceIntent =新的意图（ServiceStartActivity.this，
MyService.class）;
getApplicationContext（）。bindService（serviceIntent，
mTestServiceConnection，Context.BIND_AUTO_CREATE）;
}
@覆盖
保护无效的onStop（）{
super.onStop（）;
。getApplicationContext（）unbindService（mTestServiceConnection）;
}
公共类RunOnServiceProgress实现Runnable {
@覆盖
公共无效的run（）{
//做一些事情上的用户界面！
}
}
}
解决方案
我现在
startService（serviceIntent）; 您使用绑定到服务之前， getApplicationContext（）bindService（serviceIntent，mTestServiceConnection，Context.BIND_AUTO_CREATE ）;
原因：：当你开始使用服务bindService（），就变成了绑定服务的
只运行只要其他应用程序组件绑定到它。
如果你以一个服务 startService（）将
可以在后台运行下去，
所以，如果你有例如一个progessbar上的用户界面，并且希望它继续更新，你应该开始你的服务，并绑定与undbind它onResume（）/的onPause（）。但要carfull：既然你手动启动该服务，您也应该停止手动。要做到这一点最简单的方法是调用 stopSelf（）一旦业务做了它的工作。
该soultion涵盖如与一个活动的适当结合一个progresss条相同的服务，即使该活动被破坏或改变方向时后。
Again a question about LocalServices. How do I (re-)bind to an existing Service, after onDestroy()?
The Problem:
I'm binding to a Service and Starting the service from an Activity. I'm Posting runnable Objects to the Binder, for a callback (updating a progressbar) on the UI. When I close this Activity, the OS could end the lifecycle and Destroy the Activity, calling onDestroy(), right? I simulate this, calling finish() in onPause() method. So once I restart the Activity, how to I bind to the SAME Service again? I thought that Services are Singelton, but when I'm trying to re-bind, I get another binder reference. So binder.callbackHandler.post(binder.progressHandler); still has the reference to the old binder/callback/progressHandler, not to my new one.
Even the Constructor of the Service is called again!
Is there any solution to have a progressbar, getting updated by callback objects from the service (working). Closing/onDestroy() the Activity. Come back, and continue the progressbar?
My code is quite large, but recreated the Szenario:
public class MyService extends Service {
private final LocalBinder binder = new LocalBinder();
public class LocalBinder extends Binder implements TestRunServiceBinder {
private Handler callbackHandler;
private ServiceStartActivity.RunOnServiceProgress onProgress;
@Override
public void setActivityCallbackHandler(Handler messageHandler) {
callbackHandler = messageHandler;
}
@Override
public void setServiceProgressHandler(RunOnServiceProgress runnable) {
onProgress = runnable;
}
public void doSomething(){
_doSomething();
};
private void _doSomething(){
while(...){
//do this a couple of times (could take up to 10min)
binder.callbackHandler.post(binder.progressHandler);
wait()
}
}
}
_
public class ServiceStartActivity{
private final Handler messageHandler = new Handler();
private ServiceConnection mTestServiceConnection = new ServiceConnection() {
@Override
public void onServiceDisconnected(ComponentName name) {
testRunBinder = null;
}
@Override
public void onServiceConnected(ComponentName name, IBinder service) {
testRunBinder = (TestRunServiceBinder) service;
testRunBinder.setActivityCallbackHandler(messageHandler);
testRunBinder.setServiceProgressHandler(new RunOnServiceProgress());
}
};
@Override
protected void onStart() {
super.onStart();
// bind to the Service
final Intent serviceIntent = new Intent(ServiceStartActivity.this,
MyService.class);
getApplicationContext().bindService(serviceIntent,
mTestServiceConnection, Context.BIND_AUTO_CREATE);
}
@Override
protected void onStop() {
super.onStop();
getApplicationContext().unbindService(mTestServiceConnection);
}
public class RunOnServiceProgress implements Runnable {
@Override
public void run() {
//do something on the UI!
}
}
}
I got it now. The solution is to explicit call startService(serviceIntent); before you bind to the Service using getApplicationContext().bindService(serviceIntent,mTestServiceConnection, Context.BIND_AUTO_CREATE);
Reason: When you start a Service with bindService(), it becomes a Bound Service an
runs only as long as another application component is bound to it.
If you start a Service with startService() it can
can run in the background indefinitely,
So if you have e.g. a progessbar on the UI, and you want it to continue updating it, you should start your Service, and bind and undbind it in onResume() / onPause(). But be carfull: Since you started the Service manually, You should also stop it manually. The simplest way to do this is call stopSelf() once the Service did it's work.
This soultion covers a proper binding from an Activity with e.g. an progresss bar to the same Service even after the activity is destroyed or after an orientation change.
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