How to keep the backlight on(Android,Qt 5.1 RC1)?

[peterlin82]

I develop android app with Qt 5.1.0 RC1.
I want to keep the backlight on.

#include <android/native_activity.h>
 
ANativeActivity *theActivity;
ANativeActivity_setWindowFlags(theActivity,AWINDOW_FLAG_KEEP_SCREEN_ON,0);

#include <android/native_activity.h>

ANativeActivity *theActivity;
ANativeActivity_setWindowFlags(theActivity,AWINDOW_FLAG_KEEP_SCREEN_ON,0);

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but compile error:
undefined reference to 'ANativeActivity_setWindowFlags'

Someone can help me?
thanks a lot.

[gabizzz]

add #include <android/window.h>