GroupLayout: Vertical and Horizontal Groups

问题

I'm attempting to create a small Jpanel with a GroupLayout infront of it. Having followed the documentation as much as possible as well as looked at a number of StackOverflow questions, I'm still stuck.

The error is as follows:

Exception in thread "AWT-EventQueue-0" java.lang.IllegalStateException: javax.swing.JButton[,0,0,0x0,invalid,alignmentX=0.0,alignmentY=0.5,border=com.apple.laf.AquaButtonBorder$Dynamic@5eef2e7c,flags=288,maximumSize=,minimumSize=,preferredSize=,defaultIcon=,disabledIcon=,disabledSelectedIcon=,margin=javax.swing.plaf.InsetsUIResource[top=0,left=2,bottom=0,right=2],paintBorder=true,paintFocus=true,pressedIcon=,rolloverEnabled=false,rolloverIcon=,rolloverSelectedIcon=,selectedIcon=,text=Invest,defaultCapable=true] is not attached to a vertical group

I know that the problem is related to where the buttons are being attached. After all the error says it explicitly. However, I just can't figure out in what manner I'm supposed to attach them. Any ideas?

    JPanel panel = new JPanel();

    GroupLayout layout = new GroupLayout(panel);
    panel.setLayout(layout);


    panel.setMinimumSize(new Dimension(2000,100));      
    panel.setBorder(BorderFactory.createTitledBorder((cdo.getTicker()) + " : (" + cdo.getCurrency() + ")"));


    layout.setVerticalGroup(
            layout.createSequentialGroup()
            .addGroup(layout.createParallelGroup(GroupLayout.Alignment.BASELINE)
                    .addComponent(new JButton("Invest")))                       
                    .addGroup(layout.createParallelGroup(GroupLayout.Alignment.BASELINE)
                            .addComponent(new JButton("Ignore")))
                            .addGroup(layout.createParallelGroup(GroupLayout.Alignment.BASELINE)
                                    .addComponent(new JButton("Article")))

            );


    layout.setHorizontalGroup(
            layout.createSequentialGroup()
            .addGroup(layout.createParallelGroup(GroupLayout.Alignment.LEADING)
                    .addComponent(new JButton("Invest"))
                    .addComponent(new JButton("Ignore"))
                    .addComponent(new JButton("Article"))
                    )
            );

回答1:

new JButton("Invest") creates a new button, which is different from the button previously created using new JButton("Invest").

Move the initializations of the buttons before the layout:

JButton investButton = new JButton("Invest");
JButton articleButton = new JButton("Article");
JButton ignoreButton = new JButton("Ignore");

layout.setVerticalGroup(
    layout.createSequentialGroup()
        .addGroup(layout.createParallelGroup(GroupLayout.Alignment.BASELINE)
            .addComponent(investButton))                       
        .addGroup(layout.createParallelGroup(GroupLayout.Alignment.BASELINE)
            .addComponent(ignoreButton))
        .addGroup(layout.createParallelGroup(GroupLayout.Alignment.BASELINE)
            .addComponent(articleButton)));

layout.setHorizontalGroup(
    layout.createSequentialGroup()
        .addGroup(layout.createParallelGroup(GroupLayout.Alignment.LEADING)
            .addComponent(investButton)
            .addComponent(ignoreButton)
            .addComponent(articleButton)));

来源：https://stackoverflow.com/questions/18159812/grouplayout-vertical-and-horizontal-groups

标签

java

swing

grouplayout