java中的接口是类吗
306
2023-04-09
Java弹簧布局管理器使用方法详解
由 SpringLayout 类实现的布局管理器称为弹簧布局管理器。利用该布局管理器管理组件,当改变窗体的大小时,能够在不改变组件间相对位置的前提下自动调整组件大小,使组件依旧布满整个窗体,从而保证了窗体的整体效果。下面,通过一个实例来看看弹簧布局管理器的使用方法和效果。
弹簧布局管理器以容器和组件的边缘为操作对象,通过为组件和容器边缘以及组件和组件边缘建立约束,实现对组件布局的管理。通过方法 putConstraint(String e1,Conponet c1,int pad,String e2,Componet c2)可以为各边之间建立约束,该方法的入口参数说明如下:
c1:需要参考的组件对象;
c2:需要参考的组件对象的具体需要参考的边;
e1:被参考的组件对象;
e2:被参考的组件对象的具体被参考的边;
pad:两条边之间的距离,即两个组件之间的间距。
有点绕,其实很好理解。
MEZmcEbV 实例1:使用弹簧布局管理器。
本实例利用弹簧布局管理器实现窗体,在调整窗体的大小后,组件仍会布满整个窗体,并且组件间的相对位置并不会改变。源码:
import java.awt.Container;
import java.awt.event.WindowAdapter;
import java.awt.event.WindowEvent;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.jscrollPane;
import javax.swing.JTextArea;
import javax.swing.JTextField;
import javax.swing.Spring;
import javax.swing.SpringLayout;
public class SpringLayout_3 extends JFrame {
private static final long serialVersionUID = -6045918631932051025L;
public SpringLayout_3() {
// TODO Auto-generated constructor stub
Container container = getContentPane();
SpringLayout springLayout = new SpringLayout();
container.setLayout(springLayout);
JLabel topicLabel = new JLabel("主题 :");
JLabel contentLabel = new JLabel("内容 :");
final JTextField textField = new JTextField(30);
JTextArea textArea = new JTextArea(3, 30);
JScrollPane scrollPane = new JScrollPane();
scrollPane.setViewportView(textArea);
textArea.setLineWrap(true);
final JButton confirmButton = new JButton("取消");
JButton cancelButton = new JButton("确认");
Spring st = Spring.constant(10);
Spring st2 = Spring.constant(30);
container.add(topicLabel);
springLayout.putConstraint(SpringLayout.NORTH, topicLabel, st,
SpringLayout.NORTH, container);
springLayout.putConstraint(SpringLayout.WEST, topicLabel, st,
SpringLayout.WEST, container);
container.add(textField);
springLayout.putConstraint(SpringLayout.WEST, textField, st2,
SpringLayout.EAST, topicLabel);
springLayout.putConstraint(SpringLayout.NORTH, textField, 0,
SpringLayout.NORTH, topicLabel);
springLayout.putConstraint(SpringLayout.EAST, textField, Spring.minus(st),
SpringLayout.EAST, container);
container.add(contentLabel);
springLayout.putConstraint(SpringLayout.WEST, contentLabel, 0,
SpringLayout.WEST, topicLabel);
springLayout.putConstraint(SpringLayout.NORTH, contentLabel, st,
SpringLayout.SOUTH, topicLabel);
container.add(scrollPane);
springLayout.putConstraint(SpringLayout.NORTH, scrollPane, 0,
SpringLayout.NORTH, contentLabel);
springLayout.putConstraint(SpringLayout.WEST, scrollPane, 0,
SpringLayout.WEST, textField);
springLayout.putConstraint(SpringLayout.EAST, scrollPane, Spring.minus(st),
SpringLayout.EAST, cMEZmcEbVontainer);
container.add(confirmButton);
springLayout.putConstraint(SpringLayout.SOUTH, scrollPane, Spring.minus(st),
SpringLayout.NORTH, confirmButton);
springLayout.putConstraint(SpringLayout.EAST, confirmButton, Spring.minus(st),
SpringLayout.EAST, container);
springLayout.putConstraint(SpringLayout.SOUTH, confirmButton, Spring.minus(st),
SpringLayout.SOUTH, container);
container.add(cancelButton);
springLayout.putConstraint(SpringLayout.EAST, cancelButton, Spring.minus(st),
SpringLayout.WEST, confirmButton);
springLayout.putConstraint(SpringLayout.NORTH, cancelButton, 0,
SpringLayout.NORTH, confirmButton);
// make the text field focused every time the window is activated
addWindowFocusListener(new WindowAdapter() {
@Override
public void windowGainedFocus(WindowEvent e) {
// TODO Auto-generated method stub
textField.requestFocus();
}
});
}
public static void main(String[] args) {
// TODO Auto-generated method stub
SpringLayout_3 frame = new SpringLayout_3();
frame.setTitle("使用弹簧布局管理器");
frame.setVisible(true);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setBounds(100, 100, 600, 300);
}
}
总结
以上就是弹簧布局管理器的使用方法及实例,喜欢的同学快去试试效果吧。
感谢大家对我们的支持!
版权声明:本文内容由网络用户投稿,版权归原作者所有,本站不拥有其著作权,亦不承担相应法律责任。如果您发现本站中有涉嫌抄袭或描述失实的内容,请联系我们jiasou666@gmail.com 处理,核实后本网站将在24小时内删除侵权内容。
发表评论
暂时没有评论,来抢沙发吧~