[android] Clear Application's Data Programmatically

I'm just putting the tutorial from the link ihrupin posted here in this post.

package com.hrupin.cleaner;

import java.io.File;

import android.app.Application;
import android.util.Log;

public class MyApplication extends Application {

    private static MyApplication instance;

    @Override
    public void onCreate() {
        super.onCreate();
        instance = this;
    }

    public static MyApplication getInstance() {
        return instance;
    }

    public void clearApplicationData() {
        File cacheDirectory = getCacheDir();
        File applicationDirectory = new File(cacheDirectory.getParent());
        if (applicationDirectory.exists()) {
            String[] fileNames = applicationDirectory.list();
            for (String fileName : fileNames) {
                if (!fileName.equals("lib")) {
                    deleteFile(new File(applicationDirectory, fileName));
                }
            }
        }
    }

    public static boolean deleteFile(File file) {
        boolean deletedAll = true;
        if (file != null) {
            if (file.isDirectory()) {
                String[] children = file.list();
                for (int i = 0; i < children.length; i++) {
                    deletedAll = deleteFile(new File(file, children[i])) && deletedAll;
                }
            } else {
                deletedAll = file.delete();
            }
        }

        return deletedAll;
    }
}

So if you want a button to do this you need to call MyApplication.getInstance(). clearApplicationData() from within an onClickListener

Update: Your SharedPreferences instance might hold onto your data and recreate the preferences file after you delete it. So your going to want to get your SharedPreferences object and

prefs.edit().clear().commit();

Update:

You need to add android:name="your.package.MyApplication" to the application tag inside AndroidManifest.xml if you had not done so. Else, MyApplication.getInstance() returns null, resulting a NullPointerException.