How to delete cache-folder of app?

Question

I read through the Android documentation of the cache (see Data Storage Documentation) but I didn't got how I can clean the whole folder.

So how can I delete the cache-folder of my app? It's in this path:

/Android/data/de.stepforward/cache/

Answer 1

Put this code in onDestroy() to clear app cache:

void onDestroy() { super.onDestroy();

    try {
        trimCache(this);
       // Toast.makeText(this,"onDestroy " ,Toast.LENGTH_LONG).show();
    } catch (Exception e) {
        // TODO Auto-generated catch block
        e.printStackTrace();
    }

}

public static void trimCache(Context context) {
    try {
       File dir = context.getCacheDir();
       if (dir != null && dir.isDirectory()) {
          deleteDir(dir);
       }
    } catch (Exception e) {
       // TODO: handle exception
    }
 }

 public static boolean deleteDir(File dir) {
    if (dir != null && dir.isDirectory()) {
       String[] children = dir.list();
       for (int i = 0; i < children.length; i++) {
          boolean success = deleteDir(new File(dir, children[i]));
          if (!success) {
             return false;
          }
       }
    }

    // The directory is now empty so delete it
    return dir.delete();
 }

Answer 2

You can use the code referenced here:

https://stackoverflow.com/a/7600257/327011

File cacheDir = context.getCacheDir();

File[] files = cacheDir.listFiles();

if (files != null) {
    for (File file : files)
       file.delete();
}

Answer 3

Kotlin:

You can make use of File.deleteRecursively() from the standard library to remove all sub directories as well

To delete the whole cache directory of the app:

context.cacheDir.deleteRecursively()

To delete a specific directory in the cache including its sub directories

File(context.cacheDir, "child directory name").deleteRecursively()

Thanks for the suggestion @elyeante

Answer 4

Rather than rolling your own utility methods, you may want to consider using the apache commons FileUtils library. It contains a lot of useful File manipulation methods and makes operations like this very trivial.

Here are the JavaDocs

And here is an example:

try {
    FileUtils.deleteDirectory(context.getCacheDir());
} catch (IOException e) {
    Log.e(LOGTAG,"Error deleting cache dir", e);
}

Alternately, rather than deleting the whole cache directory, you may want to create subdirectories within the app's cache directory for specific data. Than you can delete those specific directories when required (e.g. on user logout).