不能更新外观和感觉吗?

I have a program that I want to be able to switch between "day" and "night" modes, with the "night" mode having 50% gray backgrounds on everything. I'm doing this by calling UIManager.put(key, new color) for all of the "background" keys from this page:

我有一个程序，我希望能够在“白天”和“夜”模式之间切换，“夜”模式有50%的灰色背景。我是通过调用UIManager来实现的。从这一页的“背景”键中输入(键，新颜色):

http://alvinalexander.com/java/java-uimanager-color-keys-list

Then I use SwingUtilities.updateComponentTreeUI() in conjunction with java.awt.Window.getWindows() to get existing windows to pick up the change.

然后，我使用swinguse . updatecomponenttreeui()和java.awt.Window.getWindows()来获取现有的窗口来获取更改。

When I switch modes, newly-created windows will have the proper background, so the first part works. However, existing windows are behaving oddly: they flash to the new color for a moment, and then switch back. Thus e.g. if I start up the program in Day mode, then the main program window is effectively stuck in Day mode, and vice versa.

当我切换模式时，新创建的窗口会有合适的背景，所以第一部分工作。然而，现有的windows操作系统却表现得很奇怪:它们在一瞬间闪现出新的颜色，然后切换回来。因此，如果我在Day模式下启动程序，那么主程序窗口就会在Day模式中被有效地卡住，反之亦然。

I attempted to make an example program. It doesn't behave exactly like my existing program, but it still behaves oddly: the look and feel can only be modified once. After that, new changes are ignored:

我试图做一个示例程序。它的行为与我现有的程序不一样，但它仍然表现得很奇怪:外观和感觉只能修改一次。在那之后，新的变化被忽略了:

import java.awt.Color;
import java.awt.Dimension;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.Frame;
import javax.swing.JLabel;
import java.awt.GridLayout;
import java.util.Random;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.SwingUtilities;
import javax.swing.UIManager;


public class Demo {
   public static void main(String[] args) {
      new Demo();
   }

   public Demo() {
      JFrame frame = new JFrame("Look and feel test");
      frame.setLayout(new GridLayout(3, 3));
      // Fill in non-central locations in the layout.
      // Hacky way to keep the button from monopolizing the frame
      for (int i = 0; i < 4; ++i) {
         frame.add(new JLabel(""));
      }
      JButton button = new JButton("Set new LAF");
      button.addActionListener(new ActionListener() {
         @Override
         public void actionPerformed(ActionEvent e) {
            setNewLAF();
         }
      });
      frame.add(button);
      // Fill in non-central locations in the layout.
      for (int i = 0; i < 4; ++i) {
         frame.add(new JLabel(""));
      }
      frame.setMinimumSize(new Dimension(400, 400));
      frame.show();
      System.out.println("Initial frame background is " + frame.getBackground());
   }

   public void setNewLAF() {
      Random rng = new Random();
      Color newBackground = new Color(rng.nextInt(255),
            rng.nextInt(255), rng.nextInt(255));
      System.out.println("New color is " + newBackground);
      UIManager.put("Panel.background", newBackground);
      for (Frame f : Frame.getFrames()) {
         SwingUtilities.updateComponentTreeUI(f);
         System.out.println("Frame now has background " + f.getBackground());     
      }
   }
}

This produces output such as:

这产生的输出如下:

Initial frame background is com.apple.laf.AquaImageFactory$SystemColorProxy[r=238,g=238,b=238]
New color is java.awt.Color[r=243,g=209,b=134]
Frame now has background java.awt.Color[r=243,g=209,b=134]
New color is java.awt.Color[r=205,g=141,b=58]
Frame now has background java.awt.Color[r=243,g=209,b=134]
New color is java.awt.Color[r=141,g=22,b=92]
Frame now has background java.awt.Color[r=243,g=209,b=134]

Thanks for any advice you'd care to share.

谢谢你给我的建议。

2 个解决方案

#1

it still behaves oddly: the look and feel can only be modified once.

它仍然表现得很奇怪:外观和感觉只能被修改一次。

Color newBackground = new Color(rng.nextInt(255),rng.nextInt(255), rng.nextInt(255));

You need to use:

你需要使用:

Color newBackground = new ColorUIResource(rng.nextInt(255),rng.nextInt(255), rng.nextInt(255));

The updateComponentTreeUI() only replaces resources that are part of the UI. You do this by wrapping the Color in a ColorUIResource.

updateComponentTreeUI()只是替换了UI中一部分的资源。您可以通过在ColorUIResource中包装颜色来实现这一点。

#2

Why don't you replace your UIManager based code with something like this?

你为什么不把你的UIManager代码替换成这样?

public void setNewLAF(JFrame frame) {
    Random rng = new Random();
    Color newBackground = new Color(rng.nextInt(255), rng.nextInt(255),
            rng.nextInt(255));
    System.out.println("New color is " + newBackground);
    frame.setBackground(newBackground);
    frame.getContentPane().setBackground(newBackground);
}

It might not work well with your case (e.g., if you have many frames) but I think that you can probably just dump your frames into an ArrayList<JFrame> and iterate over them.

它可能不适用于您的情况(例如，如果您有许多帧)，但是我认为您可能只是将您的框架转储到一个ArrayList 并遍历它们。

Also, just to let you know: show() is deprecated. Use setVisible(true).

另外，只是让您知道:show()是不赞成的。使用setVisible(true)。

#1