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(Stringe1,Conponetc1,intpad,Stringe2,Componetc2)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。
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:
importjava.awt.Container; importjava.awt.event.WindowAdapter; importjava.awt.event.WindowEvent; importjavax.swing.JButton; importjavax.swing.JFrame; importjavax.swing.JLabel; importjavax.swing.JScrollPane; importjavax.swing.JTextArea; importjavax.swing.JTextField; importjavax.swing.Spring; importjavax.swing.SpringLayout; publicclassSpringLayout_3extendsJFrame{ privatestaticfinallongserialVersionUID=-6045918631932051025L; publicSpringLayout_3(){ //TODOAuto-generatedconstructorstub Containercontainer=getContentPane(); SpringLayoutspringLayout=newSpringLayout(); container.setLayout(springLayout); JLabeltopicLabel=newJLabel("主题:"); JLabelcontentLabel=newJLabel("内容:"); finalJTextFieldtextField=newJTextField(30); JTextAreatextArea=newJTextArea(3,30); JScrollPanescrollPane=newJScrollPane(); scrollPane.setViewportView(textArea); textArea.setLineWrap(true); finalJButtonconfirmButton=newJButton("取消"); JButtoncancelButton=newJButton("确认"); Springst=Spring.constant(10); Springst2=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,container); 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); //makethetextfieldfocusedeverytimethewindowisactivated addWindowFocusListener(newWindowAdapter(){ @Override publicvoidwindowGainedFocus(WindowEvente){ //TODOAuto-generatedmethodstub textField.requestFocus(); } }); } publicstaticvoidmain(String[]args){ //TODOAuto-generatedmethodstub SpringLayout_3frame=newSpringLayout_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。
感谢大家对毛票票的支持!