Question

我正在尝试从活动中加载地图片段。

活动代码：

package com.example.project;

import android.app.ListActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.Adapter;
import android.widget.AdapterView;
import android.widget.AdapterView.OnItemClickListener;
import android.widget.ListView;
import android.widget.Toast;

public class VehicleListActivity extends ListActivity {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        // TODO Auto-generated method stub
        super.onCreate(savedInstanceState);
        setContentView(R.layout.list_viewer);

        ListView list = getListView();
        ListAdapter adapter = new ListAdapter(getApplicationContext());

        list.setAdapter(adapter);
        list.setItemsCanFocus(true);

        list.setOnItemClickListener
        (
                new OnItemClickListener()
                {

                    @Override
                    public void onItemClick(AdapterView<?> arg0, View arg1,
                            int arg2, long arg3) {
                        // TODO Auto-generated method stub
                        Toast.makeText(getApplicationContext(), "you hav clicked", Toast.LENGTH_LONG).show();

                        Adapter adapter = arg0.getAdapter();
                        String vehicleNumber = ((VehicleDetails) adapter.getItem(arg2)).getVehicleNumber();
                        double latitude = ((VehicleDetails) adapter.getItem(arg2)).getLatitude();
                        double longitude = ((VehicleDetails) adapter.getItem(arg2)).getLongitude();

                        Bundle data = new Bundle();
                        data.putString("VEHICLE_No", vehicleNumber);
                        data.putDouble("LATITUDE", latitude);
                        data.putDouble("LONGITUDE", longitude);

                        MapLoaderFragment map = new MapLoaderFragment();
                        map.setArguments(data);

                    }

                }
        );
    }

}

片段类代码：

package com.example.project;

import com.google.android.gms.common.GooglePlayServicesNotAvailableException;
import com.google.android.gms.maps.CameraUpdateFactory;
import com.google.android.gms.maps.GoogleMap;
import com.google.android.gms.maps.MapView;
import com.google.android.gms.maps.MapsInitializer;
import com.google.android.gms.maps.model.BitmapDescriptorFactory;
import com.google.android.gms.maps.model.CameraPosition;
import com.google.android.gms.maps.model.LatLng;
import com.google.android.gms.maps.model.Marker;
import com.google.android.gms.maps.model.MarkerOptions;

import android.os.Bundle;
import android.support.v4.app.Fragment;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;

public class MapLoaderFragment extends Fragment {
	
	MapView mapView;
	GoogleMap map;
	
	public MapLoaderFragment()
	{
	}
	
	@Override
	public void onCreate(Bundle savedInstanceState)
	{
		super.onCreate(savedInstanceState);
	}

	@Override
	public View onCreateView(LayoutInflater inflater, ViewGroup container,
			Bundle savedInstanceState) {
		// TODO Auto-generated method stub
		
		String vehicleNumber = getArguments().getString("VEHICLE_NO");
		double latitude = getArguments().getDouble("LATITUDE");
		double longitude = getArguments().getDouble("LONGITUDE");
		
		View view = inflater.inflate(R.layout.map_fragment, container, false);
		
		mapView = (MapView) view.findViewById(R.id.map);
		mapView.onCreate(savedInstanceState);
		
		map = mapView.getMap();
		
		try {
			MapsInitializer.initialize(this.getActivity());
		} catch (GooglePlayServicesNotAvailableException e) {
			e.printStackTrace();
		}
		
		LatLng position = new LatLng(latitude, longitude);
		Marker marker = map.addMarker(new MarkerOptions());
		marker.setTitle(vehicleNumber);
		marker.setPosition(position);
		marker.setIcon(BitmapDescriptorFactory.fromResource(R.drawable.car));
		
		CameraPosition cameraPosition = new CameraPosition.Builder().target(
				position).zoom(15).build();
		map.animateCamera(CameraUpdateFactory.newCameraPosition(cameraPosition));
		
		return view;
	}

	@Override
	public void onDestroy() {
		// TODO Auto-generated method stub
		mapView.onDestroy();
		super.onDestroy();
	}

	@Override
	public void onResume() {
		// TODO Auto-generated method stub
		mapView.onResume();
		super.onResume();
	}

}

这是我到目前为止所做的。在主要活动中我加载列表，添加点击监听器列表。从点击我试图通过发送纬度经度和车辆号码加载地图。

MainActivity.xml代码：

<?xml version="1.0" encoding="utf-8"?>
<ListView xmlns:android="http://schemas.android.com/apk/res/android"
    android:id="@android:id/list"
    android:layout_width="match_parent"
    android:layout_height="match_parent" />

地图片段代码：

<?xml version="1.0" encoding="utf-8"?>    
<fragment
    xmlns:android="http://schemas.android.com/apk/res/android"
    android:id="@+id/map"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    class="com.google.android.gms.maps.SupportMapFragment" />

Answer 1

主要有两种方法可以将片段用于活动。

静态：在活动的布局文件中声明片段。

或者

动态：以编程方式将片段添加到现有。

在您的代码中似乎您没有以编程方式插入片段，那么您的问题将在您的xml布局中。

此处的基本示例：http://developer.android.com/guide/components/fragments.html

Answer 2

您没有将MapLoaderFragment放置到任何片段容器中。通常，您的XML布局文件中将有一个容器来容纳该片段，然后在您将拥有的调用活动中

MapLoaderFragment map = new MapLoaderFragment();
map.setArguments(data);
...
FragmentManager fm = getFragmentManager();
fm.beginTransaction()
.add(container, map)
.commit();

片段没有膨胀

2 个答案: