java-自定义JComboBox顶部标签
作者:互联网
希望这是一个简单的问题.
从“提供自定义渲染器”部分的http://download.oracle.com/docs/cd/E17409_01/javase/tutorial/uiswing/components/combobox.html的示例中,我可以制作一个JComboBox
Picture 3 - Text 3
-------------------
Picture 1 - Text 1
Picture 2 - Text 2
Picture 3 - Text 3
Picture 4 - Text 4
Picture 5 - Text 5
图片3-文本3是当前选择的项目.
是否可以有自定义标签?如
Text 3
-------------------
Picture 1 - Text 1
Picture 2 - Text 2
Picture 3 - Text 3
Picture 4 - Text 4
Picture 5 - Text 5
组合框处于最小化状态时不显示图像的位置.
我以前使用过JButton /未修饰的弹出式JFrame进行仿真,但想知道是否可以使用纯JComboBox
谢谢
解决方法:
Is it possible to have a custom label?
Such as…
是.使用相同的渲染器渲染下拉列表和组合框中的选定项目.当“渲染器索引”为-1时,选定的值为渲染器,因此您可以根据需要自定义渲染.就像是:
import java.awt.*;
import java.awt.event.*;
import java.util.*;
import javax.swing.*;
import javax.swing.plaf.basic.*;
public class ComboBoxItemIcon extends JFrame
{
public ComboBoxItemIcon()
{
Vector model = new Vector();
model.addElement( new Item(new ImageIcon("copy16.gif"), "copy" ) );
model.addElement( new Item(new ImageIcon("add16.gif"), "add" ) );
model.addElement( new Item(new ImageIcon("about16.gif"), "about" ) );
JComboBox comboBox;
comboBox = new JComboBox( model );
comboBox.setRenderer( new ItemRenderer() );
getContentPane().add(comboBox, BorderLayout.SOUTH );
}
class ItemRenderer extends BasicComboBoxRenderer
{
public Component getListCellRendererComponent(
JList list, Object value, int index,
boolean isSelected, boolean cellHasFocus)
{
super.getListCellRendererComponent(list, value, index,
isSelected, cellHasFocus);
Item item = (Item)value;
if (index == -1)
{
setText( item.getText() );
setIcon( null );
}
else
{
setText( item.getText() );
setIcon( item.getIcon() );
}
return this;
}
}
class Item
{
private Icon icon;
private String text;
public Item(Icon icon, String text)
{
this.icon = icon;
this.text = text;
}
public Icon getIcon()
{
return icon;
}
public String getText()
{
return text;
}
}
public static void main(String[] args)
{
JFrame frame = new ComboBoxItemIcon();
frame.setDefaultCloseOperation( EXIT_ON_CLOSE );
frame.pack();
frame.setVisible( true );
}
}
标签:jcombobox,swing,java,user-interface 来源: https://codeday.me/bug/20191209/2097597.html