通过包名获取 启动的 intent （推荐使用）
public static Intent getMainIntent(Context context, String packageName) {
return context.getPackageManager().getLaunchIntentForPackage(packageName);
}
Intent intent = getMainIntent(getApplicationContext(), "com.zuimeia.suite.lockscreen.international");
intent.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
intent.putExtra(EXTRA_LAYOUT_ID, themeid);
startActivity(intent);
通过包名和MainActivity 名字来启动：
Intent intent = new Intent(Intent.ACTION_MAIN);
intent.addCategory(Intent.CATEGORY_LAUNCHER);
ComponentName cn = new ComponentName(packageName, className);
intent.setComponent(cn);
startActivity(intent);
