Swing，添加JTextField，将我的JPanel删除。

Having a strange problem. I'm learning Java Swing right now, and have a basic frame with a set size. I added buttons, and then radio buttons, and everything was fine. I add a JTextField and everything goes blank on the Frame until I manually resize it and then everything appears. I've tried messing around with Grids and GridBagConstraints and nothing seems to be helping, but I don't have a very good handle on working with those just yet. Everything is sized correctly I believe, but the box opens up blank and then when I change the size even by a single pixel in any direction, everything shows up fine.

有一个奇怪的问题。我现在正在学习Java Swing，并且有一个具有设置大小的基本框架。我添加了按钮，然后是单选按钮，一切都很好。我添加了一个JTextField，所有的东西都在这个框架上空白，直到我手动调整它的大小，然后一切都出现了。我尝试过用网格和网格约束来解决问题，似乎没有什么帮助，但是我还没有很好的处理这些问题。我相信所有的东西都是正确的，但是盒子是空白的，当我改变大小的时候，哪怕是一个像素的方向，一切都会好起来的。

Here is my code so far:

下面是我的代码:

import javax.swing.*;

import java.awt.*;

public class Test {

    private JFrame f; //frame
    private JPanel p; //window
    private JButton b1; //button
    private JButton b2; //button
    private JButton b3; //button
    private JButton b4; //button
    private JRadioButton rad1;
    private JRadioButton rad2;
    private String radBut1 = "Checking";
    private String radBut2 = "Savings";
    private JTextField textField;


public Test(){

    gui();

}

public void gui(){      

    f = new JFrame("ATM Machine");
    f.setVisible(true);
    f.setSize(350,200);
    f.setLocationRelativeTo(null);
    //f.setResizable(false);
    f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

    p = new JPanel();

    b1 = new JButton("Withdraw From");
    b2 = new JButton("Deposit To");
    b3 = new JButton("Transfer To");
    b4 = new JButton("Balance Of");

    b1.setPreferredSize(new Dimension(150,25));
    b2.setPreferredSize(new Dimension(150,25));
    b3.setPreferredSize(new Dimension(150,25));
    b4.setPreferredSize(new Dimension(150,25));

    p.add(b1);
    p.add(b2);
    p.add(b3);
    p.add(b4);

    rad1 = new JRadioButton(radBut1);
    rad2 = new JRadioButton(radBut2);






    ButtonGroup radioGroup = new ButtonGroup();
    radioGroup.add(rad1);
    radioGroup.add(rad2);

    p.add(rad1);
    p.add(rad2);

    textField = new JTextField(25);

    p.add(textField);


    f.add(p);




}

public static void main(String[] args) {

    new Test();


}

}

So basically it needs to look like 2 buttons on top, 2 buttons underneath those buttons, 2 radio buttons under those, and then finally the TextField under the radio buttons.

基本上它需要看起来像两个按钮在上面，两个按钮在这些按钮下面，两个在这些按钮下面，最后是在单选按钮下的TextField。

I would appreciate any help.

我很感激你的帮助。

Thanks!

谢谢!

1 个解决方案

#1

Components should be added to the frame BEFORE making the frame visible.

在使框架可见之前，应该将组件添加到框架中。

f = new JFrame("ATM Machine");
//f.setVisible(true);
...
f.add(p);
f.setVisible(true);

and have a basic frame with a set size.

并且有一个基本的框架和一个固定的大小。

Don't set the size of the frame. Let Swing determine the size of each component and the size of the frame. So really the code should be:

不要设置框架的大小。让Swing确定每个组件的大小和框架的大小。所以代码应该是:

f.add(p);
f.pack();
f.setVisible(true);

Don't set the preferredSize() of your buttons. If you want all the buttons to be the same size, then use a GridLayout on a separate panel:

不要设置按钮的优先级()。如果您希望所有按钮的大小相同，则在单独的面板上使用GridLayout:

JPanel buttons = new JPanel( new GridLayout(0, 4) );
buttons.add(b1);
buttons.add(b2);
...

Then you add the buttons panel to the frame.

然后将按钮面板添加到框架中。

Also, you need to change the layout manager. Right now you are using a FlowLayout and the layout only appears to work correctly. If you resize the frame components will flow to another line. Maybe you need to use a BoxLayout.

另外，您需要更改布局管理器。现在您正在使用一个流布局，而布局只显示正确工作。如果您调整框架组件的大小，则会流向另一行。也许你需要使用一个方框布局。

Read the Swing tutorial on Using Layout Manager for more information.

阅读Swing教程，使用布局管理器获取更多信息。

#1