Java 如何创建动态大小的JScrollPane w/JPanel作为客户端?
在我的代码中,用户可以使用菜单向主JPanel添加新按钮。JPanel利用FlowLayout表单,因此根据窗口的大小,每行上的数量或按钮都会发生变化,以适应最佳视图。。。在我介绍JScrollPane之前,情况就是这样。现在我有两个问题:Java 如何创建动态大小的JScrollPane w/JPanel作为客户端?,java,swing,scroll,jscrollpane,Java,Swing,Scroll,Jscrollpane,在我的代码中,用户可以使用菜单向主JPanel添加新按钮。JPanel利用FlowLayout表单,因此根据窗口的大小,每行上的数量或按钮都会发生变化,以适应最佳视图。。。在我介绍JScrollPane之前,情况就是这样。现在我有两个问题: 一旦用户将窗口大小重新调整为首选大小或更低,每行上的#个按钮将停止更改*以前没有这个问题,即使设置了首选大小 我只能滚动查看JPanel首选大小范围内的按钮。放置在外部的任何内容都无法查看,并且不会增加JScrollPane范围的大小 代码如下: packa
package testit;
import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.Dimension;
import java.awt.FlowLayout;
import java.awt.Insets;
import java.awt.Toolkit;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.KeyEvent;
import javax.swing.ImageIcon;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JMenu;
import javax.swing.JMenuBar;
import javax.swing.JMenuItem;
import javax.swing.JPanel;
import javax.swing.JScrollPane;
import javax.swing.KeyStroke;
import javax.swing.border.LineBorder;
class TestIt extends JFrame implements ActionListener {
//Main window frame, content panel and scroll pane
private JFrame main_frame;
private JPanel main_panel;
private JScrollPane main_scroll;
//Screen size
private Dimension screen = Toolkit.getDefaultToolkit().getScreenSize();
public TestIt() {
//Set up the main frame
main_frame = new JFrame("Test Program");
main_frame.setLayout(new BorderLayout());
main_frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
main_frame.setIconImage(
new ImageIcon("src/testit/resources/img/app_icon.gif").getImage());
//Set up the content panel and add it to the scroll pane
main_panel = new JPanel();
main_panel.setLayout(new FlowLayout());
main_panel.setPreferredSize(
new Dimension(screen.width/10 * 6, screen.height/10 * 6));
main_scroll = new JScrollPane(main_panel);
//Add the menu bar and the scroll pane to the main frame
main_frame.add(main_scroll, BorderLayout.CENTER);
main_frame.setJMenuBar(createMenuBar());
//Display the main GUI
main_frame.pack();
main_frame.setLocationRelativeTo(null);
main_frame.setVisible(true);
}
private JMenuBar createMenuBar() {
//Create the top menu bar
JMenuBar top_menu_bar = new JMenuBar();
//Create the menu
JMenu main_menu = new JMenu ("Menu");
main_menu.setMnemonic(KeyEvent.VK_M);
top_menu_bar.add(main_menu);
//Create the menu items and add them to the menu
JMenuItem menu_item;
menu_item = new JMenuItem("Add New");
menu_item.setMnemonic(KeyEvent.VK_N);
menu_item.setAccelerator(
KeyStroke.getKeyStroke(KeyEvent.VK_N, ActionEvent.ALT_MASK));
menu_item.setActionCommand("new");
menu_item.addActionListener(this);
main_menu.add(menu_item);
menu_item = new JMenuItem("Save");
menu_item.setMnemonic(KeyEvent.VK_S);
menu_item.setAccelerator(
KeyStroke.getKeyStroke(KeyEvent.VK_S, ActionEvent.ALT_MASK));
menu_item.setActionCommand("save");
menu_item.addActionListener(this);
main_menu.add(menu_item);
menu_item = new JMenuItem("Exit");
menu_item.setMnemonic(KeyEvent.VK_X);
menu_item.setAccelerator(
KeyStroke.getKeyStroke(KeyEvent.VK_X, ActionEvent.ALT_MASK));
menu_item.setActionCommand("exit");
menu_item.addActionListener(this);
main_menu.add(menu_item);
//Return the assembled menu bar
return top_menu_bar;
}
@Override
public void actionPerformed(ActionEvent e) {
switch (e.getActionCommand()) {
case "new":
createThumb();
break;
case "save":
break;
default:
quit();
break;
}
}
private void createThumb() {
//Width and height for the thumbnail button
final int H = 170;
final int W = 150;
//Set up the thumbnail button
ImageIcon image = new ImageIcon("src/testit/resources/img/test.gif");
JButton thumb = new JButton(image);
thumb.setMargin(new Insets(0, 0, 0, 0));
thumb.setBorder(new LineBorder(Color.BLACK));
thumb.setBackground(Color.BLACK);
thumb.setPreferredSize(new Dimension(W, H));
thumb.addActionListener(new ActionListener() {
@Override
public void actionPerformed(ActionEvent e) {
openNewFrame();
}
});
main_panel.add(thumb);
main_panel.validate();
}
private void openNewFrame() {
JFrame new_window = new JFrame();
new_window.setPreferredSize(new Dimension(400, 800));
new_window.pack();
new_window.setLocationRelativeTo(null);
new_window.setVisible(true);
}
private void quit() {
System.exit(0);
}
//Create an instance of the program
private static void runIt() {
TestIt program = new TestIt();
}
public static void main(String [] args) {
javax.swing.SwingUtilities.invokeLater(new Runnable() {
@Override
public void run() {
runIt();
}
});
}
}
我尝试了很多方法,我一直在挖掘Javadoc。。。。我已经阅读了很多内容和教程,但仍然无法使我的滚动/重新调整大小工作。当您设置组件的首选大小时,您可以修改其大小,因此它不会在JScrollPane中展开。一个解决方案是不这样做,不固定容纳JButtons的容器的大小 e、 g
我喜欢!不过,有一个问题是,当我增加窗口的宽度时,它会增加按钮的宽度。这是因为GridLayout与FlowLayout的本质不同吗?有没有办法防止GridLayout拉伸拇指?我猜将Resizeable设置为false或强制设置最大宽度可以做到这一点。。。但我想知道是否还有其他方法?
import java.awt.BorderLayout;
import java.awt.Dimension;
import java.awt.GridLayout;
import java.awt.Toolkit;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.KeyEvent;
import javax.swing.*;
@SuppressWarnings("serial")
public class TestIt2 extends JPanel {
private static final Dimension THUMB_SIZE = new Dimension(170, 150);
private Dimension screen = Toolkit.getDefaultToolkit().getScreenSize();
private JPanel thumbPanel = new JPanel(new GridLayout(0, 6, 5, 5));
public TestIt2() {
JPanel holderPanel = new JPanel(new BorderLayout());
holderPanel.add(thumbPanel, BorderLayout.NORTH);
holderPanel.add(Box.createGlue(), BorderLayout.CENTER);
setLayout(new BorderLayout());
add(new JScrollPane(holderPanel), BorderLayout.CENTER);
}
public JMenuBar createMenuBar() {
JMenuBar top_menu_bar = new JMenuBar();
JMenu main_menu = new JMenu("Menu");
main_menu.setMnemonic(KeyEvent.VK_M);
top_menu_bar.add(main_menu);
JMenuItem menu_item;
menu_item = new JMenuItem("Add New");
menu_item.setMnemonic(KeyEvent.VK_N);
menu_item.setAccelerator(KeyStroke.getKeyStroke(KeyEvent.VK_N,
ActionEvent.ALT_MASK));
menu_item.setActionCommand("new");
menu_item.addActionListener(new ActionListener() {
@Override
public void actionPerformed(ActionEvent arg0) {
createThumb();
}
});
main_menu.add(menu_item);
return top_menu_bar;
}
protected void createThumb() {
JButton thumb = new JButton("Thumb");
thumb.setPreferredSize(THUMB_SIZE);
thumbPanel.add(thumb);
revalidate();
repaint();
}
@Override
public Dimension getPreferredSize() {
return new Dimension(screen.width / 10 * 6,
screen.height / 10 * 6);
}
private static void createAndShowGui() {
TestIt2 mainPanel = new TestIt2();
JFrame frame = new JFrame("TestIt2");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.getContentPane().add(mainPanel);
frame.setJMenuBar(mainPanel.createMenuBar());
frame.pack();
frame.setLocationByPlatform(true);
frame.setVisible(true);
}
public static void main(String[] args) {
SwingUtilities.invokeLater(new Runnable() {
public void run() {
createAndShowGui();
}
});
}
}