使用JCheckBox帮助创建JTree

Question

我有一个不寻常的情况,我需要一个JTree,每个节点包含2个复选框和一个标签(能够添加一个监听器,以告知何时检查任何潜在的复选框).我还需要根节点具有相同的布局(我假设这意味着创建一个带有2个JCheckBox和JLabel的JPanel),如果选中了根中的一个,则可以选择树下的所有复选框.

任何指导或例子？我已经在这里查看了之前的问题和相关的例子......其中一些让我能够让树"看起来",但没有给我一个实现其背后动作的方向.

谢谢!

Answer 1

这可能是查看旧JTreeTable代码的好时机,它将为您提供在第一列中呈现的树,并且可以根据需要自由地将每个列的单元格呈现在树节点的右侧,在您的情况下放入复选框和标签,并允许您像以前一样让TableCellEditors与JTable一起使用.一个警告是,虽然该链接中的代码有效,但它有点复杂.

还有另一种选择.我在下面演示了一个更好的树表实现,称为OutlineNetBeans提供的实现(虽然您不需要使用NetBeans IDE进行开发,但您只需要jar). 本文指出了入门是多么容易.

我能够在大约30分钟内模拟Eclipse中大纲树表的快速示例(将org-netbeans-swing-outline.jar导入到我的项目中)(我输入速度慢):

private void buildFrame() {
    frame = new JFrame("Demo");
    frame.setSize(300, 300);
    addStuffToFrame();
    frame.setVisible(true);

}


private void addStuffToFrame() {
    MyTreeNode top = new MyTreeNode("top");
    createNodes(top);
    DefaultTreeModel model = new DefaultTreeModel(top);     
    //here are the netBeans tree table classes 
    OutlineModel outlineModel = 
             DefaultOutlineModel.createOutlineModel(model, new MyRowModel());
    Outline outline = new Outline();
    outline.setRootVisible(true);
    outline.setModel(outlineModel);
    frame.getContentPane().add(new JScrollPane(outline));
}

private void createNodes(MyTreeNode top) {
    MyTreeNode child = new MyTreeNode("child 2");
    top.add(new MyTreeNode("child 1"));
    child.add(new MyTreeNode("g-child1"));
    child.add(new MyTreeNode("g-child2"));
    child.add(new MyTreeNode("g-child3"));
    top.add(child);
    top.add(new MyTreeNode("child3"));
    top.add(new MyTreeNode("child4"));

}

我创建了一个TreeNode来保存Boolean与JTable内置复选框渲染机制完全互操作的s.

public class MyTreeNode extends DefaultMutableTreeNode {
    Boolean data1 = null;
    Boolean data2 = null;
    String name = null;
    MyTreeNode (String name) {
        this.name=name;
    }

    void setData1(Boolean val) {data1=val;}
    void setData2(Boolean val) {data2=val;}
    Boolean getData1() {return data1;}
    Boolean getData2() {return data2;}
    String getName() {return name;}

}

netBeans RowModel是使其成为表而不是简单JTree的关键:

public class MyRowModel implements RowModel {

    public Class getColumnClass(int col) {
        switch (col) {
        case 0: return String.class;
        case 1: return Boolean.class; //these return class definitions will
        case 2: return Boolean.class; //trigger the checkbox rendering
        default:return null;    
        }
    }

    public int getColumnCount() {
        return 3;
    }

    public String getColumnName(int col) {
        return "";
    }

    public Object getValueFor(Object node, int col) {
        MyTreeNode n = (MyTreeNode)node;
        switch (col) {
        case 0: return n.getName();
        case 1: return n.getData1();
        case 2: return n.getData2();
        default:return null;
        }
    }

    public boolean isCellEditable(Object node, int col) {
        return col > 0;
    }

    public void setValueFor(Object node, int col, Object val) {
        MyTreeNode n = (MyTreeNode)node;
        if (col == 1)      {n.setData1((Boolean)val);}
        else if (col == 2) {n.setData2((Boolean)val);}
        //EDIT:  here is a recursive method to set all children
        //       selected for one of the two checkboxes as it is 
        //       checked by the parent
        for (Enumeration children = n.children();
                       children.hasMoreElements(); ) {
            MyTreeNode child = (MyTreeNode) children.nextElement();
            setValueFor(child, col, val);
        }


    }

}

这是完成的,虽然简单的产品:

替代文字http://img17.imageshack.us/img17/6643/picture1hz.png

我更新了setValueFor迭代节点子节点的方法,并在修改父节点时将复选框设置为选中或取消选中.