How to Focus GUI.TextArea in Unity for Android

In Unity Editor, I could focus a GUI.TextArea by doing the following:

 GUI.SetNextControlName("MyTextField");
 m = GUI.TextArea(new Rect(0f, 0f, 100f, 100f), m, 64,style);
 GUI.FocusControl("MyTextField");

However, this doesn't work in Android devices. Instead, I had to tap the text area to focus it and bring up the TouchScreenKeyboard.

What should I do to programmatically set focus on GUI.TextArea for Android devices.