判断隐式Intent是否有响应

PackageManager manager = getContext().getPackageManager();
if (manager.queryIntentActivities(intent, 0).size() > 0) {
　　startActivity(intent);
}

// Verify that the intent will resolve to an activity
if (sendIntent.resolveActivity(getPackageManager()) != null) {
    startActivity(sendIntent);
}