Java Swing中如何识别触发PropertyChangeListener的具体组件

方法1：通过PropertyChangeEvent的source传递触发组件 #

修改ThemeManager的主题设置方法，允许传入触发变更的组件，并在触发事件时将该组件作为事件源（或保留原source，将组件存入事件的userData）：

public class ThemeManager {
    private String theme;
    // ... 其他成员

    public void setTheme(String newTheme, Component triggerComponent) {
        String oldTheme = this.theme;
        this.theme = newTheme;
        // 触发事件时携带触发组件
        firePropertyChange("theme", oldTheme, newTheme);
        // 若需保留ThemeManager作为source，可改用自定义事件传递组件
    }
}

在触发主题变更的组件（如单选按钮）的监听器中，调用setTheme时传入自身：

settingsLightThemeRadioButton.addActionListener(e -> {
    themeManager.setTheme("light", settingsLightThemeRadioButton);
});

最后在ThemeManagerFrame的propertyChange方法中获取触发组件：

@Override
public void propertyChange(PropertyChangeEvent evt) {
    if ("theme".equals(evt.getPropertyName())) {
        String newTheme = (String) evt.getNewValue();
        // 获取触发组件
        Component trigger = (Component) evt.getSource();
        System.out.println("Theme changed by: " + trigger.getName());
        
        // 同步ButtonGroup示例：根据触发组件更新其他组的选中状态
        if (trigger == settingsLightThemeRadioButton) {
            otherButtonGroup.getElements().asIterator().forEach(btn -> {
                if ("light".equals(btn.getActionCommand())) {
                    btn.setSelected(true);
                }
            });
        }
        // ... 其他UI更新逻辑
    }
}

方法2：自定义事件类携带触发组件 #

若需保留ThemeManager作为事件源，可自定义PropertyChangeEvent子类存储触发组件：

public class ThemeChangeEvent extends PropertyChangeEvent {
    private final Component triggerComponent;

    public ThemeChangeEvent(Object source, String propertyName, Object oldValue, Object newValue, Component triggerComponent) {
        super(source, propertyName, oldValue, newValue);
        this.triggerComponent = triggerComponent;
    }

    public Component getTriggerComponent() {
        return triggerComponent;
    }
}

修改ThemeManager的触发逻辑：

public void setTheme(String newTheme, Component triggerComponent) {
    String oldTheme = this.theme;
    this.theme = newTheme;
    firePropertyChange(new ThemeChangeEvent(this, "theme", oldTheme, newTheme, triggerComponent));
}

在监听器中强转事件获取组件：

@Override
public void propertyChange(PropertyChangeEvent evt) {
    if ("theme".equals(evt.getPropertyName()) && evt instanceof ThemeChangeEvent) {
        ThemeChangeEvent themeEvent = (ThemeChangeEvent) evt;
        String newTheme = (String) themeEvent.getNewValue();
        Component trigger = themeEvent.getTriggerComponent();
        
        System.out.println("Theme changed by: " + (trigger != null ? trigger.getName() : "Unknown"));
        // 同步ButtonGroup逻辑...
    }
}

方法3：在触发源直接同步组件 #

如果不需要在全局监听器中识别组件，可在触发主题变更的组件监听器中直接同步其他ButtonGroup，避免后续监听器处理：

settingsLightThemeRadioButton.addActionListener(e -> {
    // 先同步另一个ButtonGroup的选中状态
    otherButtonGroup.setSelected(settingsLightThemeRadioButton.getModel(), true);
    // 再通知主题变更
    themeManager.setTheme("light");
});

内容的提问来源于stack exchange，提问作者IssaKass