第一次开始片段后，地图不显示位置按钮

Question

  

我有一个名为TestMap的地图片段。当它首先加载时   时间，它从方法显示当前位置和位置按钮   setMyLocationButtonEnabled(true)。当它首先加载后   时间不显示当前位置和位置按钮.........              知道为什么吗？

... TestMap

 package com.example.map;

import com.google.android.gms.maps.GoogleMap;
import com.google.android.gms.maps.SupportMapFragment;

import android.os.Bundle;
import android.support.v4.app.Fragment;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.Toast;

public class TestMap extends Fragment{
    public  GoogleMap gmap;
    View view;

    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
    }

    public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState){

        view = inflater.inflate(R.layout.findmap, container, false);
        initializemap();
        gmap.setMyLocationEnabled(true);
        // gmap.getUiSettings().setMyLocationButtonEnabled(true);

        return view;
    }

    private void initializemap() {
        // TODO Auto-generated method stub
        if(gmap == null){
            gmap = ((SupportMapFragment) getFragmentManager().findFragmentById(R.id.mapView))
                    .getMap();
        }
        if (gmap == null) {
            Toast.makeText(getActivity(),
                    "Sorry! unable to create maps", Toast.LENGTH_SHORT)
                    .show();
        }   
    }

    public void onResume(){
        super.onResume();
        // initializemap();
    }

    public void onDestroyView() {
        super.onDestroyView();
        SupportMapFragment f = (SupportMapFragment) getFragmentManager().findFragmentById(R.id.mapView);
        if (f != null){ 
            getFragmentManager().beginTransaction().remove(f).commitAllowingStateLoss();
        } 
    } 

}

Answer 1

setMyLocationButtonEnabled()默认为true。

     // Show current location    
        gmap.setMyLocationEnabled(true);
     //  Location button
     //comment this line gmap.getUiSettings().setMyLocationButtonEnabled(true);