How to programmatically clear application data

I am developing automated tests for an android application (using Robotium). In order to ensure the consistency and reliability of tests开发者_高级运维, I would like to start each test with clean state (of the application under test). In order to do so, I need to clear the app data. This can be done manually in Settings/Applications/Manage Applications/[My App]/Clear data

What is the recommended way to get this done programmatically?

You can use the package-manager tool to clear data for installed apps (similar to pressing the 'clear data' button in the app settings on your device). So using adb you could do:

adb shell pm clear my.wonderful.app.package

Following up to @edovino's answer, the way of clearing all of an application's preferences programmatically would be

private void clearPreferences() {
    try {
        // clearing app data
        Runtime runtime = Runtime.getRuntime();
        runtime.exec("pm clear YOUR_APP_PACKAGE_GOES HERE");

    } catch (Exception e) {
        e.printStackTrace();
    }
}

Warning: the application will force close.

you can clear SharedPreferences app-data with this

Editor editor = 
context.getSharedPreferences(PREF_FILE_NAME, Context.MODE_PRIVATE).edit();
editor.clear();
editor.commit();

and for clearing app db, this answer is correct -> Clearing Application database

From API version 19 it is possible to call ActivityManager.clearApplicationUserData().

((ActivityManager) context.getSystemService(Context.ACTIVITY_SERVICE)).clearApplicationUserData();

Check this code to:

@Override
protected void onDestroy() {
// closing Entire Application
    android.os.Process.killProcess(android.os.Process.myPid());
    Editor editor = getSharedPreferences("clear_cache", Context.MODE_PRIVATE).edit();
    editor.clear();
    editor.commit();
    trimCache(this);
    super.onDestroy();
}


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;
            }
        }
    }

    // <uses-permission
    // android:name="android.permission.CLEAR_APP_CACHE"></uses-permission>
    // The directory is now empty so delete it

    return dir.delete();
}

If you have just a couple of shared preferences to clear, then this solution is much nicer.

@Override
protected void setUp() throws Exception {
    super.setUp();
    Instrumentation instrumentation = getInstrumentation();
    SharedPreferences preferences = instrumentation.getTargetContext().getSharedPreferences(...), Context.MODE_PRIVATE);
    preferences.edit().clear().commit();
    solo = new Solo(instrumentation, getActivity());
}

Using Context,We can clear app specific files like preference,database file. I have used below code for UI testing using Espresso.

    @Rule
    public ActivityTestRule<HomeActivity> mActivityRule = new ActivityTestRule<>(
            HomeActivity.class);

    public static void clearAppInfo() {
        Activity mActivity = testRule.getActivity();
        SharedPreferences prefs =
                PreferenceManager.getDefaultSharedPreferences(mActivity);
        prefs.edit().clear().commit();
        mActivity.deleteDatabase("app_db_name.db");
    }

if android version is above kitkat you may use this as well

public void onClick(View view) {

    Context context = getApplicationContext(); // add this line
    if (Build.VERSION_CODES.KITKAT <= Build.VERSION.SDK_INT) {
        ((ActivityManager) context.getSystemService(ACTIVITY_SERVICE))
            .clearApplicationUserData();
        return;
    }

What is the recommended way to get this done programmatically?

The only possible option is to run ADB command adb shell pm clear package before the test. The biggest problem is that it's kind of headache combining tests execution and shell commands.

However, we (at Mediafe) came with some solution that can work for you on regular unrooted device. All you need to do is to add an annotation. All the rest is done by running simple bash script.

Just add @ClearData annotation before ANY of your tests and tada