在 Java 中显示弹出消息窗口？
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Display pop-up message window in Java?
提问by Howcan
I read about JDialogs and JOptionPane messages but I still can't get it to work. I have a GUI class that extends JFrame. All I want to do is have a popup at the beginning of my program which informs the user about a couple of things. In my main I create the following gui:
我阅读了 JDialogs 和 JOptionPane 消息，但我仍然无法让它工作。我有一个扩展 JFrame 的 GUI 类。我想要做的就是在我的程序开始时弹出一个窗口，通知用户一些事情。在我的主要我创建以下gui：
GUI g = new GUI();
Right after that I was to display the window. I have tried the following in the main method:
在那之后，我要显示窗口。我在主要方法中尝试了以下内容：
JOptionPane.showMessageDialog(g, "work?");
JOptionPane.showMessageDialog(frame, "work?"); //(frame was used in documentation example so I tried it)
I also tried to add the pop up into the GUI class with the following
我还尝试使用以下内容将弹出窗口添加到 GUI 类中
JOptionPane.showMessageDialog(this, "work?"); //(I'm not exactly sure what the Frame Owner parameter is supposed to be, unless I'm confusing this with JDialog.)
In any case, how would I make this window appear? Every single one of the methods I tried compiled, and nothing happened.
无论如何，我将如何使这个窗口出现？我尝试编译的每一种方法都没有发生。
public class GUI extends JFrame implements ActionListener{
private Container background;
private static buttons etc...
private static JLabel disp,edisp;
private static JTextArea info;
//setting up the GUI for my program, adding action listeners, I can post more if necessary
}
And then I have the main where I want to call the pop up window
然后我有我想调用弹出窗口的主要内容
public static void main(String[] args){
GUI g = new GUI();
JOptionPane.showMessageDialog(g,"Work?");
}
回答by Otanan
Make sure that these are called near the beginning, be it in the main method or not. Also, try just setting the first parameter as null. So it reads:
确保这些在开头附近被调用，无论是否在 main 方法中。另外，尝试将第一个参数设置为 null。所以它写道：
JOptionPane.showMessageDialog(null,"Work?");
Also, remember to import it!
还有，记得导入哦！
