如何更改Java程序单个部分的外观

Question

因此，我正在制作一个程序选择工具，目前，我只喜欢Java外观就喜欢所有外观。我唯一想更改的是Windows的JFileChooser外观。当我打电话给filechooser并告诉它更改外观时，它什么也没做。当我在程序启动时调用它时，它会使按钮显得糟糕。所以谷歌没有任何东西，我不知道如何使它工作。请帮忙！让我知道哪些代码将是相关且有用的。提前致谢！

编辑：所以这是JFileChooser及其启动方式的一些代码关系：

public class Start(){
    public static JButton assignButton = new JButton(new AbstractAction(
        "Assign") {
    public void actionPerformed(ActionEvent e) {
        AssignWindow.run();
    }
});
}

public class AssignmentWindow(){
   public static void run() {
    Dialogs.assignmentInfo();

    bgImage = aw.getImage("files/background.png");

            //aw is the object of this class
    aw.makeFrame();     //makes the jframe for all the buttons to sit.
    aw.setGraphics();   //assigns a different graphics variable

    aw.fileChooser();
}

public void fileChooser() {
    JFileChooser jfc = new JFileChooser();
    jfc.setFileSelectionMode(JFileChooser.FILES_AND_DIRECTORIES);

            // here is where i want to set the look and feel....

    if (jfc.showDialog(null, "Select") == JFileChooser.APPROVE_OPTION) {
        File file = jfc.getSelectedFile();
        fileDir = file.getPath();
    } else {
        Dialogs.msg("You cancled selecting a file. Returning to file frame...");
        AssignWindow.destroy();
    }
}
}

Answer 1

所有需要做的就是在创建JFileChooser对象时更改UIManager，然后将其设置回之前的状态，或者您可以仅捕获Exception，但这是一个不好的做法。

public void stuff(){
    JFileChooser chooser = null;
    LookAndFeel previousLF = UIManager.getLookAndFeel();
    try {
        UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
        chooser = new JFileChooser();
        UIManager.setLookAndFeel(previousLF);
    } catch (IllegalAccessException | UnsupportedLookAndFeelException | InstantiationException | ClassNotFoundException e) {}
    //Add whatever other settings you want to the method
    chooser.showOpenDialog(frame);
}