我正在做一个应用程序,它必须通过键盘读取一些字符并对其进行解释。
为了捕获密钥,我打开一个JDialog并设置一个KeyEventDispatcher,这样我就可以捕获dispatchKeyEvent方法中的字符。在JDialog中,有一个按钮可以删除KeyEventDispatcher并处理JDialog。
它有两个问题:
-第一次打开JDialog时,就像没有设置KeyEventDispatcher一样
-当我关闭和打开这个JDialog时,KeyEventDispatchers正在累积(打开第一次,没有运行;打开第二次,有一个运行,打开第三次,有两个运行,…)
KeyEventDispatchers似乎是在JDialog关闭而未删除时设置的,而不是在JDiallog打开并关闭时删除时设置。
有人能帮我了解发生了什么以及我该如何解决吗?
以下是JDialog类的简化版本(只有密钥捕获部分):
public class SequenceDialog {
private JDialog dialog;
private JButton finishButton;
private DialogKeyEventDispatcher keyEventDispatcher;
public SequenceDialog() {
initializeDialog();
}
private void initializeDialog() {
dialog = new JDialog();
finishButton = new JButton("Finish");
finishButton.addActionListener(new FinishButtonListener());
dialog.setModalityType(ModalityType.APPLICATION_MODAL);
dialog.add(finishButton);
setKeyListener();
dialog.setVisible(true);
dialog.pack();
}
/** Adds the KeyEventDispacther */
private void setKeyListener() {
keyEventDispatcher = new DialogKeyEventDispatcher();
KeyboardFocusManager manager = KeyboardFocusManager
.getCurrentKeyboardFocusManager();
manager.addKeyEventDispatcher(keyEventDispatcher);
}
private class FinishButtonListener implements ActionListener {
public void actionPerformed(ActionEvent e) {
//Removing the KeyEventDispacther
KeyboardFocusManager manager = KeyboardFocusManager
.getCurrentKeyboardFocusManager();
manager.removeKeyEventDispatcher(keyEventDispatcher);
dialog.dispose();
}
}
/** The KeyEventDispatcher to be executed */
private class DialogKeyEventDispatcher implements KeyEventDispatcher {
public boolean dispatchKeyEvent(KeyEvent e) {
if(e.getID() == KeyEvent.KEY_PRESSED) {
System.out.println(KeyEvent.getKeyText(e.getKeyCode()));
}
return false;
}
}
}
如果有另一种捕捉钥匙的方法,我会很高兴看到的。到目前为止,我已经尝试过:
- KeyListener,即使在我将其添加到JButton和contentPane时也不起作用
- KeyEventPostProcessor具有与使用KeyEventDispatcher相同的效果
- KeyBinding,不起作用,似乎不是最好的选择,因为我必须捕获键入的所有内容
无法再现未在上工作的情况。
可以复制堆叠:通过单击标题中的关闭图标关闭对话框时,不会删除分配器。在这种情况下,在对话框关闭后打印在主框中键入的笔划。
在dispose和WindowListener中(而不是在finish操作中),可以可靠地删除调度器:
private void initializeDialog() {
dialog = new JDialog() {
@Override
public void dispose() {
KeyboardFocusManager manager = KeyboardFocusManager.getCurrentKeyboardFocusManager();
manager.removeKeyEventDispatcher(keyEventDispatcher);
LOG.info("disposed: " + manager);
super.dispose();
}
};
WindowListener l = new WindowAdapter() {
@Override
public void windowClosing(WindowEvent e) {
KeyboardFocusManager manager = KeyboardFocusManager.getCurrentKeyboardFocusManager();
manager.removeKeyEventDispatcher(keyEventDispatcher);
LOG.info("closing: " + manager);
}
};
dialog.addWindowListener(l);