change default Home Application

from: http://stackoverflow.com/questions/3836215/android-change-default-home-application

Method installPackageMethod = null;
Method deletePackageMethod = null;
Method setPreferredActivityMethod = null;
Method replacePreferredActivityMethod = null;
Object pm = null;


    @Override
public void onCreate() {
    super.onCreate();
        if (pm == null)
        pm = getPackageManager();
    try {
        if (setPreferredActivityMethod == null)
            setPreferredActivityMethod = pm.getClass().getMethod(
                    "addPreferredActivity", IntentFilter.class, int.class,
                    ComponentName[].class, ComponentName.class);
    } catch (NoSuchMethodException e) {
        e.printStackTrace();
    }
}


private final class ServiceHandler extends Handler {
    private Context context;

    public ServiceHandler(Looper looper, Context ctx) {
        super(looper);
        context = ctx;
    }

    @Override
    public void handleMessage(Message msg) {
        Intent intent = (Intent) msg.getData().getParcelable(
                UPDATER_SERVICE_ACTION);
        int request = intent.getIntExtra(
                REQUEST_KEY,
                REQUEST_UNKNOWN);
        Bundle bundle = intent.getExtras();

        switch (request) {
        case INSTALL_APPLICATION: {
            if (bundle != null) {
                String appPath = bundle
                        .getString(APP_PATH_KEY);
                if (appPath != null) {
                    LogUtil.e(TAG, "try to install " + appPath);

                    try {
                        am.installPackage(appPath);
                    } catch (Exception e) {
                        e.printStackTrace();
                    }

                    LogUtil.e(TAG, "install of " + appPath + " done");
                }
            }
            break;
        }
        case UNISTALL_PACKAGE: {
            if (bundle != null) {
                String packagename = bundle
                        .getString(PACKAGE_NAME_KEY);
                if (packagename != null) {
                    LogUtil.e(TAG, "unistall " + packagename);

                    try {
                        deletePackageMethod
                                .invoke(pm, packagename, null, 0);
                    } catch (Exception e) {
                        e.printStackTrace();
                    }
                }
            }
            break;
        }
        case SET_PREFERRED_LAUNCHER: {
            if (bundle != null) {
                String package_name = bundle
                        .getString(PREFERRED_PACKAGE_KEY);
                if (package_name == null) {
                    LogUtil.e(TAG,
                            "WARNING: setDefaultActivity cannot continue, package is NULL");
                    return;
                }
                String activity_name = bundle
                        .getString(PREFERRED_ACTIVITY_KEY);
                if (activity_name == null) {
                    LogUtil.e(TAG,
                            "WARNING: setDefaultActivity cannot continue, activity is NULL");
                    return;
                }

                LogUtil.e(TAG, "setDefaultActivity activity="
                        + activity_name + " package=" + package_name);

                IntentFilter filter = new IntentFilter(
                        "android.intent.action.MAIN");
                filter.addCategory("android.intent.category.HOME");
                filter.addCategory("android.intent.category.DEFAULT");
                ComponentName[] components = new ComponentName[] {
                        new ComponentName("com.android.launcher",
                                "com.android.launcher2.Launcher"),
                        new ComponentName(package_name, activity_name) };
                ComponentName activity = new ComponentName(package_name,
                        activity_name);
                try {
                    setPreferredActivityMethod.invoke(pm, filter,
                            IntentFilter.MATCH_CATEGORY_EMPTY, components,
                            activity);
                } catch (Exception e) {
                    e.printStackTrace();
                }
            }
        }
        }

    }

}