JTree:TreeCellRenderer未按预期执行

时间:2015-05-12 00:51:25

标签: java swing fonts jtree treecellrenderer

简而言之,我希望树被渲染成第一级是粗体。

public class TreeRenderer1 extends DefaultTreeCellRenderer {

@Override
public Component getTreeCellRendererComponent(JTree tree, Object value,
        boolean sel, boolean exp, boolean leaf, int row, boolean hasFocus) {
    super.getTreeCellRendererComponent(tree, value, sel, exp, leaf, row, hasFocus);

    DefaultMutableTreeNode node = (DefaultMutableTreeNode)value;

    if (node.getLevel()==1) {
        setFont(getFont().deriveFont(Font.BOLD));
    }

    return this;
}
}

然而,这会使我树中的所有节点都变粗。有什么问题?

2 个答案:

答案 0 :(得分:3)

如果级别不是1 ...

,则重置渲染的字体状态
if (node.getLevel()==1) {
    setFont(getFont().deriveFont(Font.BOLD));
} else {
    setFont(getFont().deriveFont(Font.PLAIN));
}

渲染是共享资源,您对其进行的任何更改都会传输到要渲染的下一个元素,因此您必须始终确保在某个时刻将其设置为“默认”状态

答案 1 :(得分:2)

在您的代码中,您为级别1设置了字体粗体,但其他级别则是如此。其他条件在哪里?你能试试吗?

@Override
public Component getTreeCellRendererComponent(JTree tree, Object value,
        boolean sel, boolean exp, boolean leaf, int row, boolean hasFocus) {
    super.getTreeCellRendererComponent(tree, value, sel, exp, leaf, row, hasFocus);

    DefaultMutableTreeNode node = (DefaultMutableTreeNode)value;

    if (node.getLevel()==1) {
        setFont(getFont().deriveFont(Font.BOLD));
    } else {
        setFont(getFont().deriveFont(Font.PLAIN));
    }

    return this;
}
}