是否可以在运行时更改组件样式？

Question

我使用swing + nimbus来设计我的组件.我想用"Nimbus.Overrides"在运行时更改组件的样式.

private void SetExceptionState() {
    //password.setBackground(new Color(200,0,0,120));
    UIDefaults overrides = new UIDefaults();
    overrides.put("PasswordField.background", Color.red);
    password.putClientProperty("Nimbus.Overrides", overrides);
    password.revalidate();
    password.updateUI();
}

private void ResetExceptionState() {
    //password.setBackground(Color.white);
    UIDefaults overrides = new UIDefaults();
    overrides.put("PasswordField.background", Color.white);
    password.putClientProperty("Nimbus.Overrides", overrides);
}

我第一次设置覆盖,让我们说它使用SetExceptionState()方法.我得到一个红色背景.我第二次使用这个没有任何反应.看起来,覆盖只被评估一次.

我想要的是引入一个新的密码字段状态和它的风格不同.有没有可能这样做？

最好的祝福,

Yggdrasil的

Answer 1

是的,这是可能的,Nimbus实际上听取了"Nimbus.Overrides"的变化 - 只是:它不会卸载一些属性,如果它们是!instanceof UIResource背景,前景,字体的情况至少(也可能是其他人)

在你的上下文中,你最初安装了一个RED的非资源,有效地告诉laf不再触摸它 - 它符合:-)

我能使其工作的唯一方法是在设置新覆盖之前使背景为空,如:

private void setExceptionState(JComponent password) {
    password.setBackground(null);
    UIDefaults overrides = new UIDefaults();
    overrides.put("PasswordField.background", Color.RED);
    password.putClientProperty("Nimbus.Overrides", overrides);
}

private void resetExceptionState(JComponent password) {
    password.setBackground(null);
    UIDefaults overrides = new UIDefaults();
    overrides.put("PasswordField.background", Color.WHITE);
    password.putClientProperty("Nimbus.Overrides", overrides);
}

更新

实际上,上面没有回答真正的问题:

引入密码字段的新状态并将其样式区分开来

Nimbus确实允许添加自定义状态(虽然结果有些不可预测,因为经常与Synth的那个不受爱的最小的孩子;-)走的路是

• 实现自定义状态
• 使用ui-defaults注册additonal状态
• 根据需要附加该状态的属性

所有这些配置都必须在安装LAF 之后和第一个JPasswordField实例化之前完成,如果在运行时切换LAF,很可能(没有测试)会出现问题.

protected void installCustomPasswordFieldState() {
    // implement a custom state
    State<JPasswordField> state = new State<JPasswordField>("Invalid") {

        @Override
        protected boolean isInState(JPasswordField c) {
            Object invalid = c.getClientProperty("Invalid");
            return Boolean.TRUE.equals(invalid);
        }

    };
    UIDefaults defaults = UIManager.getLookAndFeelDefaults();
    // register available states 
    // note: couldn't find a way to grab the already available states
    // so this is guesswork
    defaults.put("PasswordField.States", "Enabled, Focused, Invalid");
    // install the custom state
    defaults.put("PasswordField.Invalid", state);
    // install the properties for the custom state
    // note: background has no effect
    defaults.put("PasswordField[Invalid].background", 
            Color.RED); 
    javax.swing.Painter<JComponent> p = new javax.swing.Painter<JComponent>() {

        @Override
        public void paint(Graphics2D g, JComponent object, int width, int height) {
            g.setColor(Color.RED);
            // this is crude - overpainting the complete area, do better!
            g.fillRect(0, 0, width, height);
        }

    };
    // using a painter has an effect 
    defaults.put("PasswordField[Invalid].backgroundPainter", p);
}

// example usage, toggling
// a new property (for simplicity implemented as clientProperty
// to toggle the invalid state
Action reset = new AbstractAction("reset") {
    @Override
    public void actionPerformed(ActionEvent e) {
        boolean isInvalid = Boolean.TRUE.equals(field.getClientProperty("Invalid")); 
        if (isInvalid) {
            field.putClientProperty("Invalid", null); 
        } else {
            field.putClientProperty("Invalid", Boolean.TRUE); 
        }
        field.repaint();
    }
};