Question

我有JFileChooser并添加了2个文件扩展名过滤器，如下所示：

openFileChooser = new JFileChooser();
openFileChooser.setCurrentDirectory(new File("D:/"));
openFileChooser.setFileFilter(new FileNameExtensionFilter("OUT Files", "out"));
openFileChooser.setFileFilter(new FileNameExtensionFilter("PRN Files", "prn"));

如果我有.out文件，则我的逻辑有效，但是当我选择.prn文件时，.out文件的逻辑适用于.prn文件。我的问题是如何捕获哪种类型以及if（.out文件）->做其他事情（.prn文件）->做些什么？

Answer 1

我无法清楚地理解您的问题/问题，因此，我将为您提供一个带有2个过滤器的文件选择器示例，可能会对您有所帮助。以下JFileChooser允许用户仅选择 Mp3 和 Mp4 文件（在您的情况下是.out / .prn文件？）。阅读代码中的注释。

import java.io.File;

import javax.swing.JFileChooser;
import javax.swing.filechooser.FileFilter;

public class FileChooserExample {
    public static void main(String[] args) {
        String home = System.getProperty("user.home");
        File desktop = new File(home, "Desktop");
        JFileChooser chooser = new JFileChooser(desktop);
        // Add filter for mp3 files.
        chooser.addChoosableFileFilter(new FileFilter() {

            @Override
            public String getDescription() {
                return "Mp3 Files";
            }

            @Override
            public boolean accept(File f) {
                // Show only mp3 Files(which can be selected) and folders (which can be OPENED)
                return isMp3(f) || f.isDirectory();
            }
        });
        // Add filter for mp4 files.
        chooser.addChoosableFileFilter(new FileFilter() {

            @Override
            public String getDescription() {
                return "Mp4 Files";
            }

            @Override
            public boolean accept(File f) {
                // Show only mp4 Files(which can be selected) and folders (which can be OPENED)
                return isMp4(f) || f.isDirectory();
            }
        });
        // Only files allowed. If it is a directory, do not select it but open it to
        // choose files
        chooser.setFileSelectionMode(JFileChooser.FILES_ONLY);
        // Remove the "All files" filter. We want only our custom file filters to take
        // action.
        chooser.setAcceptAllFileFilterUsed(false);
        if (chooser.showOpenDialog(null) == JFileChooser.APPROVE_OPTION) {
            File selectedFile = chooser.getSelectedFile();
            if (isMp3(selectedFile)) {
                System.out.println("This is an mp3 file, and i wanna dance.");
            } else if (isMp4(selectedFile)) {
                System.out.println("This is an mp4 file, and i wanna grab pop corn.");
            }
        }
    }

    private static boolean isMp4(File f) {
        return f.getName().toLowerCase().endsWith(".mp4");
    }

    private static boolean isMp3(File f) {
        return f.getName().toLowerCase().endsWith(".mp3");
    }
}

如何捕获FileNameExtensionFilter并为其创建逻辑？

1 个答案: