JFrame的setUndecorated(true)内容未显示

时间:2019-03-29 13:01:45

标签: java swing

我正在用Java swing创建一个gui,应该在LCD触摸屏上实现。 gui将占据所有屏幕,并且不应关闭。因此,“ setUndecorated(true)”必不可少。 问题,当我使用它时,框架的所有内容均未显示,当我将鼠标移到按钮上时,仅显示按钮。然后,当我最大化和最小化框架时,所有内容都会出现。 这是我正在使用的代码:

public static void main(String[] args) {

    //Création de notre JFrame
    fenetre = new JFrame();
    fenetre.setTitle("IHM");
    fenetre.setSize(800, 600);
    fenetre.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    fenetre.setLocationRelativeTo(null);

    support = new JPanel();

///////Adding content to the JPanel()/////////////

    fenetre.setContentPane(support);
    fenetre.setUndecorated(true);
    fenetre.setVisible(true);

}

到目前为止,我发现的唯一解决方案是在将框架设置为可见后更改框架的大小:

fenetre.setSize(801, 601);
fenetre.setSize(800, 600);

但是我并没有真正解决问题,只是解决它。

(编辑) 我对那些不完整代码的要求。 这是一个完整的示例,您可以测试自己。 首先使用undecored设置为false对其进行测试,然后尝试使用undecored设置为true并通过最大化和最小化gui可视化窗口的内容。 最后,尝试使用代码底部的快速修复。

代码:

package test;

import java.awt.Color;
import java.awt.GridBagConstraints;
import java.awt.GridBagLayout;
import java.awt.Insets;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;

import javax.swing.JButton;
import javax.swing.JComboBox;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;

public class test {

    //Declarations
    private static JFrame fenetre;
    private static JPanel support;
    private static JLabel l1, l2;
    private static JComboBox<String> c1, c2;
    private static JButton b1, b2;

    //List to initiate the comboBoxes
    private static String[] listC1 = {"Peter", "Alex", "Jhon", "Bran"};
    private static String[] listC2 = {"10", "20", "32", "45"};

    public static void main(String[] args) {

        //Initialisation of the JFrame
        fenetre = new JFrame();
        fenetre.setTitle("IHM");
        fenetre.setSize(800, 600);
        fenetre.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        fenetre.setLocationRelativeTo(null);

        //Initialisation of the JPanel
        support = new JPanel();
        support.setBackground(Color.red);
        support.setPreferredSize(fenetre.getSize());

        //Initialisation of the components
        l1 = new JLabel("What's my name");
        l2 = new JLabel("What's my age");
        c1 = new JComboBox<String>(listC1);
        c2 = new JComboBox<String>(listC2);
        b1 = new JButton("validate name");
        b2 = new JButton("validate age");

        //Creating layout
        support.setLayout(new GridBagLayout());
        GridBagConstraints gbc = new GridBagConstraints();

        //Adding components
        gbc.fill = GridBagConstraints.BOTH;
        gbc.insets = new Insets(20, 20, 0, 0);
        gbc.gridx = 0;
        gbc.gridy = 0;
        support.add(l1, gbc);
        gbc.gridy = 1;
        support.add(c1, gbc);
        gbc.insets = new Insets(20, 20, 20, 0);
        gbc.gridy = 2;
        support.add(b1, gbc);

        gbc.insets = new Insets(20, 20, 0, 20);
        gbc.gridx = 1;
        gbc.gridy = 0;
        support.add(l2, gbc);
        gbc.gridy = 1;
        support.add(c2, gbc);
        gbc.insets = new Insets(20, 20, 20, 20);
        gbc.gridy = 2;
        support.add(b2, gbc);

        //Adding Listeners
        b1.addActionListener(new ActionListener() {
            public void actionPerformed(ActionEvent e) {
                System.out.println("My name is " + c1.getSelectedItem());
            }
        });

        b2.addActionListener(new ActionListener() {
            public void actionPerformed(ActionEvent e) {
                System.out.println("My age is " + c2.getSelectedItem());
            }
        });

        //Adding the JPanel to the content pane of the JFrame
        fenetre.setContentPane(support);

        //Setting undecorated true (switch between true and false for testing)
        fenetre.setUndecorated(false);
        fenetre.setVisible(true);

        //Quick fix, uncomment to test
        //fenetre.setSize(801, 601);
        //fenetre.setSize(800, 600);

    }
}

2 个答案:

答案 0 :(得分:0)

您没有在JPanel中添加任何按钮,那么您希望它如何显示它们?

无论哪种方式,下面都是显示按钮的简单示例:

JFrame fenetre = new JFrame();
fenetre.setTitle("IHM");
fenetre.setExtendedState(JFrame.MAXIMIZED_BOTH);
fenetre.setDefaultCloseOperation(JFrame.DO_NOTHING_ON_CLOSE);
fenetre.setLocationRelativeTo(null);

JPanel support = new JPanel();
JButton button = new JButton("button");
support.add(button);
fenetre.setContentPane(support);
fenetre.setVisible(true);

请注意,您应该使用正确的layout

我还添加了setExtendedState(JFrame.MAXIMIZED_BOTH)来填充屏幕,并添加了setDefaultCloseOperation(JFrame.DO_NOTHING_ON_CLOSE),因为您不希望关闭屏幕。

答案 1 :(得分:0)

  

问题,当我使用它时,框架的所有内容均未显示,当我将鼠标移到按钮上时,仅显示按钮。

在显示框架之前,应将组件添加到面板/框架中。

如果将组件添加到可见框架,则基本逻辑是:

panel.add(...);
panel.revalidate(); // to invoke the layout manager
panel.repaint(); // make sure panel is repainted