java - 如何更改边框颜色运行时？

Question

我正在尝试更改 JScrollPane 的边框颜色:

JScrollPane scroll = new JScrollPane (textPane, JScrollPane.VERTICAL_SCROLLBAR_AS_NEEDED, JScrollPane.HORIZONTAL_SCROLLBAR_NEVER);
Color color = new Color(150, 255, 243);
scroll.setBorder(new CompoundBorder(new EmptyBorder(3, 3, 4, 4), new LineBorder(color, 7)));

//some other code

//if smth happens then:

color = Color.red;

但是我的“滚动条”总是一样的..我怎样才能看到边框颜色的变化？

Answer 1

因为lineColor字段是 protected ，Java42有一个更简单的方法来覆盖示例中的paintBorder()方法。所以简单地做:

@Override
public void paintBorder(final Component c, final Graphics g, final int x, final int y, final int width, final int height) {
    super.lineColor = color;
    super.paintBorder(c, g, x, y, width, height);
}