标题翻译
Posting events to event queue / edt - events not passed to actionPerformed()
问题
我正在使用Java AWT事件队列进行一些测试，发布事件。
ActionEvent event = new ActionEvent(this, ActionEvent.ACTION_PERFORMED, "EVENT");
try {
Toolkit.getDefaultToolkit().getSystemEventQueue().postEvent(event);
} catch (SecurityException e) {
e.printStackTrace();
}
然后在我的JFrame中，有一个事件监听器：
public void actionPerformed(ActionEvent e) {
if (e.getActionCommand().equals("EVENT")) {
System.out.println("Event received");
}
}
问题是我在队列中发布的事件没有被分派到actionPerformed()监听器。
我进行了进一步的测试：
在我的类构造函数中：
long mask = 0xffffffffffffffffL;
Toolkit.getDefaultToolkit().addAWTEventListener(this, mask);
事件监听器：
private HashMap<Integer, Integer> seen = new HashMap<>();
@Override
public void eventDispatched(AWTEvent event) {
if (seen.containsKey(event.getID()))
seen.replace(event.getID(), seen.get(event.getID()) + 1);
else {
System.out.println(event.getID());
if (event instanceof ActionEvent)
System.out.println(((ActionEvent) event).getActionCommand());
seen.put(event.getID(), 1);
}
}
我使用了一个HashMap，因为收到的事件数量相当大，因此我只是打印出唯一的事件。
这一次，我确实得到了响应
1001
EVENT
在事件监听器eventDispatched()中，但不在actionPerformed()监听器中。
如果我从不同的线程中发布事件，例如：
Thread thread = new Thread(new Runnable() {
@Override
public void run() {
ActionEvent event = new ActionEvent(this, ActionEvent.ACTION_PERFORMED, "EVENT");
try {
Toolkit.getDefaultToolkit().getSystemEventQueue().postEvent(event);
} catch (SecurityException e) {
e.printStackTrace();
}
}
});
thread.start();
即使事件监听器也没有收到事件。
我的问题是，是否有任何方法可以将ACTION_PERFORMED事件发布到EDT（事件分派器线程）事件队列，并在actionPerformed(ActionEvent e)或其他线程的监听器中处理它？
提前谢谢！
编辑：我确实尝试过用自定义队列替换事件队列，那样可以工作，但是否有办法使用标准事件队列和EDT做同样的事情？
英文翻译
i'm doing some tests with the java awt event queue, posting events.
ActionEvent event = new ActionEvent(this, ActionEvent.ACTION_PERFORMED, "EVENT");
try {
Toolkit.getDefaultToolkit().getSystemEventQueue().postEvent(event);
} catch (SecurityException e) {
e.printStackTrace();
}
Then in my JFrame, there is a event listener:
public void actionPerformed(ActionEvent e) {
if(e.getActionCommand() == "EVENT") {
System.out.println("Event received");
}
}
the trouble is the event i've posted in the queue did not get dispatched to the actionPerformed() listener.
i did further tests:
in my class constructor:
long mask = 0xffffffffffffffffL;
Toolkit.getDefaultToolkit().addAWTEventListener(this, mask);
and the event listener:
private HashMap<Integer, Integer> seen = new HashMap<>();
@Override
public void eventDispatched(AWTEvent event) {
if(seen.containsKey(event.getID()))
seen.replace(event.getID(), seen.get(event.getID())+1);
else {
System.out.println(event.getID());
if(event instanceof ActionEvent)
System.out.println(((ActionEvent) event).getActionCommand());
seen.put(event.getID(), 1);
}
}
i used a hashmap as the number of events received is rather overwhelming, hence i simply print the unique ones.
this time round i did get a response
1001
EVENT
in the event listener eventDispatched(), but not in the action listener actionPerformed().
and if i were to post the event from a different thread e.g.
Thread thread = new Thread(new Runnable() {
@Override
public void run() {
ActionEvent event = new ActionEvent(this, ActionEvent.ACTION_PERFORMED, "EVENT");
try {
Toolkit.getDefaultToolkit().getSystemEventQueue().postEvent(event);
} catch (SecurityException e) {
e.printStackTrace();
}
}
});
thread.start();
even the event listener did not receive the event.
my question is then, is there any way that i can post an ACTION_PERFORMED event to the EDT (event dispatcher thread) event queue and have it processed in actionPerformed(ActionEvent e) or some such listeners from a different thread?
Thanks in advance!
edit: i did try to replace the event queue with a custom queue, that works, but is there a way to do the same with the standard event queue and EDT?
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