我想从 GUI 线程设置一个 HandlerThread。一段时间后，当在 GUI 上单击按钮时，它会运行 callHello()，然后将消息发送到位于非 GUI 线程上的 HelloLogger 对象，该对象异步记录“Hello World”。我已经尝试了很多东西，有些无限期地阻塞，有些永远不会收到消息等等。下面的代码或多或少与我得到的一样接近，请有人修改它以使其工作？
public class HandlerThreadExample {
private MyHandlerThread mMyHandlerThread;
private Looper mLooper;
private Handler mHandler;
public HandlerThreadExample(){
mMyHandlerThread = new MyHandlerThread();
mMyHandlerThread.start();
mLooper = mMyHandlerThread.getLooper();
}
public void callHello() {
mHandler.sendEmptyMessage(1);
}
private class MyHandlerThread extends HandlerThread {
private HelloLogger mHelloLogger;
private Handler mHandler;
public MyHandlerThread() {
super("The MyHandlerThread thread", HandlerThread.NORM_PRIORITY);
}
public void run (){
mHelloLogger = new HelloLogger();
mHandler = new Handler(getLooper()){
public void handleMessage(Message msg){
mHelloLogger.logHello();
}
};
super.run();
}
}
private class HelloLogger {
public HelloLogger (){
}
public void logHello(){
Log.d("HandlerThreadExample", "Hello World");
}
}
}
找到的最佳示例：
- 处理线程测试
- 如何创建一个 Looper 线程，然后立即向它发送消息？
- 使用 Handler 进行异步调用
- HandlerThread vs Executor - 什么时候比另一个更合适？
- HandlerThread 优于其他类似类的最佳使用
- Android 处理线程
- 处理线程示例
- Android：在主线程和工作线程之间传递数据
- Java 同步
- 使用活动线程队列和 Handler 类在线程之间发送消息
- Loopers 和处理程序简介
- developer.android：指定要在线程上运行的代码
至少现在我可以关闭该死的标签
解决方案由 pskink 提供帮助
public class HandlerThreadExample2 {
private static int MSG_START_HELLO = 0;
private static int MSG_HELLO_COMPLETE = 1;
private HandlerThread ht;
private Handler mHtHandler;
private Handler mUiHandler;
private boolean helloReady = false;
public HandlerThreadExample2(){
ht = new HandlerThread("The new thread");
ht.start();
Log.d(App.TAG, "UI: handler thread started");
mUiHandler = new Handler(){
public void handleMessage(Message msg){
if (msg.what == MSG_HELLO_COMPLETE){
Log.d(App.TAG, "UI Thread: received notification of sleep completed ");
helloReady = true; }
}
};
mHtHandler = new Handler(ht.getLooper()){
public void handleMessage (Message msg){
if (msg.what == MSG_START_HELLO){
Log.d(App.TAG, "handleMessage " + msg.what + " in " + Thread.currentThread() + " now sleeping");
try {
Thread.sleep(2000);
} catch (InterruptedException e) {
e.printStackTrace();
}
Log.d(App.TAG, "Woke up, notifying UI thread...");
mUiHandler.sendEmptyMessage(MSG_HELLO_COMPLETE);
}
}
};
}
public void sendLongHello(){
if (helloReady){
Log.d(App.TAG, "sending hello " + Thread.currentThread());
mHtHandler.sendEmptyMessage(MSG_START_HELLO);
helloReady = false;
} else {
Log.e(App.TAG, "Cannot do hello yet - not ready");
}
}
}