在KeyListener的文本字段不点火时preSS进入 [英] KeyListener in Textfield not firing when press enter
问题描述
我试图做一个程序,它可以在Java转换到华氏摄氏度。在节目我有2个标签和1文本字段输入。我想使转换温度,当用户键入温度和presses <大骨节病>输入骨节病>。要做到这一点,我添加了一个按键侦听到我的文本字段,但它不工作。当我preSS <大骨节病>输入骨节病>监听器不火的。
I'm trying to make a program that can converts fahrenheit to celcius in java. In program i have 2 Labels and 1 TextField for input. I want to make convert temperature when user types the temperature and presses Enter. To do that, i added a key listener to my textfield but it doesn't work. When i press Enter listener don't fire at all.
这是我的code。
public class TempConv extends JFrame{
private JLabel info;
private JLabel result;
private JTextField input;
private String outcome;
public TempConv(){
super("Temperature Converter");
setLayout(new BorderLayout());
info = new JLabel("Enter Fahrenheit Temperature");
add(info, BorderLayout.NORTH);
input = new JTextField(12);
add(input, BorderLayout.CENTER);
result = new JLabel("Temperature in Celcius is: " + outcome);
add(result, BorderLayout.SOUTH);
input.addKeyListener(
new KeyListener(){
public void keyPressed(KeyEvent e){
if(e.getKeyChar() == KeyEvent.VK_ENTER){
outcome = input.getText();
}
}
}
);
}
public static void main(String[] args) {
TempConv ftc = new TempConv();
ftc.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
ftc.setLocationRelativeTo(null);
ftc.setSize(370, 100);
ftc.setVisible(true);
}
}
编辑:它的工作原理与ActionListener的,但我需要用匿名类来做到这一点。如果没有匿名类它<大骨节病>输入骨节病>闪光。
It works with ActionListener but i need to do it with anonymous class. Without anonymous class it fires with Enter.
推荐答案
尝试e.getKey code()而不是e.getKeyChar()。恒KeyEvent.VK_ENTER是一个int,而不是一个字符。
Try e.getKeyCode() instead of e.getKeyChar(). The constant KeyEvent.VK_ENTER is an int, not a char.
在换句话说:
if(e.getKeyCode() == KeyEvent.VK_ENTER){
outcome = input.getText();
}
而不是
if(e.getKeyChar() == KeyEvent.VK_ENTER){
outcome = input.getText();
}
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