扩展您的Mapfragemnt作为Fragemnt ..不作为FragmentActivity ...

Extend your Mapfragemnt as Fragemnt.. Not as FragmentActivity...

然后在你的主要活动，请拨打下方code ...

Then in your main activity, call the below code...

FragmentManager fragmentManager = getSupportFragmentManager();
            FragmentTransaction fragmentTransaction = fragmentManager.beginTransaction();
            fragmentTransaction.replace(R.id.content_frame, MapActivity());
            fragmentTransaction.commit();

R.id.content_frame是里面的FrameLayout您MainActivity.xml ...

R.id.content_frame is the framelayout inside your MainActivity.xml...

我不知道什么是你给它的，因为的FrameLayout你没有张贴MainActivity.xml的ID

I dont know what is the id you gave it to that framelayout since you didnt post the MainActivity.xml