I need only one instance of my app in android. If I run my app after installation and go to Home screen, and again run my app (click on app's icon), second instance is opened, I need to open already running first instance not to run second instance. I don't know how to solve this.
Vyacheslav Shylkin
Use android:launchMode="singleTask" or android:launchMode="singleInstance" in your manifest.xml in your activity tag
来源：https://stackoverflow.com/questions/9467802/how-to-enable-only-one-instance-of-my-application