java - 如何请求JWindow临时焦点？ (Java 1.7)

是否可以请求JWindow临时焦点？有方法protected boolean requestFocusInWindow(boolean temporary)，但该方法受保护。

最佳答案

已经找到了解决方案-在扩展JWindow的类中创建了此方法：

@Override
public boolean requestFocusInWindow(boolean temporary) {
    return super.requestFocusInWindow(temporary);
}

现在，我可以请求扩展JWindow的组件的临时焦点。我将其用于JTextField的自定义弹出菜单，如果在可见的弹出窗口中选中，则插入符号的颜色会更改（当然-textField.setCaret(new HighlightCaret());是必需的）：

private class HighlightCaret extends DefaultCaret {

    private final Highlighter.HighlightPainter unfocusedPainter = new DefaultHighlighter.DefaultHighlightPainter(Color.RED);
    private final Highlighter.HighlightPainter focusedPainter = new DefaultHighlighter.DefaultHighlightPainter(new Color(10, 36, 106));
    private boolean isTemporary;

    private HighlightCaret() {
        setBlinkRate(500);
    }

    @Override
    protected Highlighter.HighlightPainter getSelectionPainter() {
        return isTemporary ? unfocusedPainter : focusedPainter;
    }

    @Override
    public void setSelectionVisible(boolean hasFocus) {
        super.setSelectionVisible(false);
        if (hasFocus) {
            super.setSelectionVisible(true);
        }
    }

    @Override
    public void focusGained(FocusEvent e) {
        isTemporary = false;
        super.focusGained(e);
    }

    @Override
    public void focusLost(FocusEvent e) {
        isTemporary = e.isTemporary();
        super.focusLost(e);
    }
}