百度地图API之Marker的使用(Android)

最近在做一个APP，其中一个功能要在地图上显示酒店位置以及显示酒店的最低价格，要用到百度地图中的Overlay。

overlay有以下几种：

　　1）Overlay：它是所有覆盖物的抽象基类，所有的覆盖物均继承此类的方法，实现用户自定义图层显示；
      2）MyLocationOverlay：一个负责显示用户当前位置的Overlay；
      3）ItemizedOverlay：它包含了一个OverlayItem列表，相当于一组分条的Overlay，通过继承此类，将一组兴趣点显示在地图上；
      4）PoiOverlay：本地搜索图层，提供某一特定地区的位置搜索服务，比如在北京市搜索“公园”，通过此图层将公园显示在地图上；
      5）RouteOverlay：步行、驾车导航线路图层，将步行、驾车出行方案的路线及关键点显示在地图上；
      6）TransitOverlay：公交换乘线路图层，将某一特定地区的公交出行方案的路线及换乘位置显示在地图上。

在3.0以后版本中百度地图api中overlay改变比较大，我刚才所说的功能在3.0以前的版本是可以通过自定义的Overlay继承ItemizedOverlay来实现，在3.0以后的版本中已经找不到ItemizedOverlay了，已经用Marker代替。官方的android demo也没有关于marker

的事例，网上资料也较少，网页版较为简单，android只能自己摸索了。

我们先来看看最终做出的效果，如下图所示：

下面是具体实现：

1.页面activity_main.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical" >
    <com.baidu.mapapi.map.MapView
        android:id="@+id/bmapView"
        android:layout_width="match_parent"
        android:layout_height="match_parent" />
</LinearLayout>

2.自定义Marker

 1 <?xml version="1.0" encoding="utf-8"?>
 2 <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
 3     android:layout_width="wrap_content"
 4     android:layout_height="wrap_content"
 5     android:orientation="vertical" >
 6     <LinearLayout
 7         android:layout_width="wrap_content"
 8         android:layout_height="wrap_content"
 9         android:background="#fea531"
10         android:gravity="center"
11         android:orientation="horizontal" >
12         <ImageView
13             android:id="@+id/img_hotel_image"
14             android:layout_width="25dp"
15             android:layout_height="25dp"
16             android:padding="2dip"
17             android:scaleType="fitXY"
18             android:src="@drawable/hotel_pic" />
19         <TextView
20             android:id="@+id/tv_hotel_price"
21             android:layout_width="wrap_content"
22             android:layout_height="wrap_content"
23             android:padding="5dip"
24             android:textColor="#ffffff"
25             android:textSize="14dp" />
26     </LinearLayout>
27     <LinearLayout
28         android:layout_width="match_parent"
29         android:layout_height="wrap_content"
30         android:gravity="center"
31         android:orientation="horizontal" >
32         <ImageView
33             android:layout_width="wrap_content"
34             android:layout_height="wrap_content"
35             android:src="@drawable/custom_marker_triangle" />
36     </LinearLayout>
37 </LinearLayout>

3.下面这段代码是关键，我们需要把自定义的view转换成Bitmap，MarkerOptions中的icon参数是Bitmap，自定义marker是很常用的，不明白百度为啥不搞个明显点方法，废了很多时间。

 1 private Bitmap getViewBitmap(View addViewContent) {
 2 
 3         addViewContent.setDrawingCacheEnabled(true);
 4 
 5         addViewContent.measure(View.MeasureSpec.makeMeasureSpec(0, View.MeasureSpec.UNSPECIFIED), View.MeasureSpec.makeMeasureSpec(0, View.MeasureSpec.UNSPECIFIED));
 6         addViewContent.layout(0, 0, addViewContent.getMeasuredWidth(), addViewContent.getMeasuredHeight());
 7 
 8         addViewContent.buildDrawingCache();
 9         Bitmap cacheBitmap = addViewContent.getDrawingCache();
10         Bitmap bitmap = Bitmap.createBitmap(cacheBitmap);
11 
12         return bitmap;
13     }

4. 下面是Activity代码，

  1 public class MainActivity extends Activity {
  2 
  3     private List<Hotel> mData;
  4     private SDKReceiver mReceiver;
  5 
  6     private MapView mMapView;
  7     private BaiduMap mBaiduMap;
  8 
  9     LocationClient mLocClient;
 10     private LocationMode mCurrentMode;
 11     public MyLocationListenner myListener = new MyLocationListenner();
 12     BitmapDescriptor mCurrentMarker;
 13 
 14     @Override
 15     protected void onCreate(Bundle savedInstanceState) {
 16         super.onCreate(savedInstanceState);
 17 
 18         SDKInitializer.initialize(getApplicationContext());
 19         setContentView(R.layout.activity_main);
 20 
 21         IntentFilter iFilter = new IntentFilter();
 22         iFilter.addAction(SDKInitializer.SDK_BROADTCAST_ACTION_STRING_PERMISSION_CHECK_ERROR);
 23         iFilter.addAction(SDKInitializer.SDK_BROADCAST_ACTION_STRING_NETWORK_ERROR);
 24         mReceiver = new SDKReceiver();
 25         registerReceiver(mReceiver, iFilter);
 26 
 27         // 地图初始化
 28         mMapView = (MapView) findViewById(R.id.bmapView);
 29         mBaiduMap = mMapView.getMap();
 30         //initLocation();
 31         mBaiduMap.setOnMarkerClickListener(new OnMarkerClickListener() {
 32             public boolean onMarkerClick(final Marker marker) {
 33                 // TO DO
 34 
 35                 return true;
 36             }
 37         });
 38         mData = getData();
 39         generateMarker();
 40 
 41     }
 42 
 43     /**
 44      * Inits the location.
 45      */
 46     private void initLocation() {
 47 
 48         // 开启定位图层
 49         mBaiduMap.setMyLocationEnabled(true);
 50         // 定位初始化
 51         mLocClient = new LocationClient(this);
 52         mLocClient.registerLocationListener(myListener);
 53         LocationClientOption option = new LocationClientOption();
 54         option.setOpenGps(true);// 打开gps
 55         option.setCoorType("bd09ll"); // 设置坐标类型
 56         option.setScanSpan(1000);
 57         mLocClient.setLocOption(option);
 58         mLocClient.start();
 59     }
 60 
 61     /**
 62      * 定位SDK监听函数
 63      */
 64     public class MyLocationListenner implements BDLocationListener {
 65         @Override
 66         public void onReceiveLocation(BDLocation location) {
 67             // map view 销毁后不在处理新接收的位置
 68             if (location == null || mMapView == null)
 69                 return;
 70             MyLocationData locData = new MyLocationData.Builder().accuracy(location.getRadius())
 71             // 此处设置开发者获取到的方向信息，顺时针0-360
 72                     .direction(100).latitude(location.getLatitude()).longitude(location.getLongitude()).build();
 73             mBaiduMap.setMyLocationData(locData);
 74 
 75             LatLng ll = new LatLng(location.getLatitude(), location.getLongitude());
 76             MapStatusUpdate u = MapStatusUpdateFactory.newLatLng(ll);
 77             mBaiduMap.animateMapStatus(u);
 78 
 79         }
 80 
 81         public void onReceivePoi(BDLocation poiLocation) {
 82         }
 83     }
 84 
 85     /**
 86      * The Class SDKReceiver.
 87      */
 88     public class SDKReceiver extends BroadcastReceiver {
 89         public void onReceive(Context context, Intent intent) {
 90             String s = intent.getAction();
 91             if (s.equals(SDKInitializer.SDK_BROADTCAST_ACTION_STRING_PERMISSION_CHECK_ERROR)) {
 92                 Toast toast = Toast.makeText(context, "key 验证出错! 请在 AndroidManifest.xml 文件中检查 key 设置", Toast.LENGTH_SHORT);
 93                 toast.setGravity(Gravity.CENTER, 0, 0);
 94                 toast.show();
 95             } else if (s.equals(SDKInitializer.SDK_BROADCAST_ACTION_STRING_NETWORK_ERROR)) {
 96                 Toast toast = Toast.makeText(context, "网络出错", Toast.LENGTH_SHORT);
 97                 toast.setGravity(Gravity.CENTER, 0, 0);
 98                 toast.show();
 99             }
100         }
101     }
102 
103     /**
104      * Gets the view bitmap.
105      *
106      * @param addViewContent
107      *            the add view content
108      * @return the view bitmap
109      */
110     private Bitmap getViewBitmap(View addViewContent) {
111 
112         addViewContent.setDrawingCacheEnabled(true);
113 
114         addViewContent.measure(View.MeasureSpec.makeMeasureSpec(0, View.MeasureSpec.UNSPECIFIED), View.MeasureSpec.makeMeasureSpec(0, View.MeasureSpec.UNSPECIFIED));
115         addViewContent.layout(0, 0, addViewContent.getMeasuredWidth(), addViewContent.getMeasuredHeight());
116 
117         addViewContent.buildDrawingCache();
118         Bitmap cacheBitmap = addViewContent.getDrawingCache();
119         Bitmap bitmap = Bitmap.createBitmap(cacheBitmap);
120 
121         return bitmap;
122     }
123 
124     /**
125      * Gets the data.
126      *
127      * @return the data
128      */
129     public List<Hotel> getData() {
130         try {
131             List<Hotel> resultList = new ArrayList<Hotel>();
132             AssetManager manager = getApplicationContext().getAssets();
133             InputStream file = manager.open("data.json");
134             byte[] data = new byte[file.available()];
135             file.read(data);
136             file.close();
137             String jsonStr = new String(data);
138             JSONObject json = JSON.parseObject(jsonStr);
139             String jsonText = json.getString("Output");
140 
141             return JSONArray.parseArray(jsonText.toString(), Hotel.class);
142 
143         } catch (IOException e) {
144             // TODO Auto-generated catch block
145             e.printStackTrace();
146             return null;
147         }
148     }
149 
150     public void generateMarker() {
151 
152         for (Iterator iterator = mData.iterator(); iterator.hasNext();) {
153             Hotel hotel = (Hotel) iterator.next();
154             LatLng ll = new LatLng(hotel.HotelLatitude, hotel.HotelLongitude);
155             View view = LayoutInflater.from(getApplicationContext()).inflate(R.layout.custom_marker, null);
156 
157             // ImageView img_hotel_image=
158             // (ImageView)view.findViewById(R.id.img_hotel_image);
159             // new
160             // DownloadImageTask(img_hotel_image).execute(hotel.getHotelImageUrl());
161 
162             TextView tv_hotel_price = (TextView) view.findViewById(R.id.tv_hotel_price);
163             tv_hotel_price.setText(new StringBuilder().append(hotel.getHotelPrice()).append("￥起"));
164             BitmapDescriptor markerIcon = BitmapDescriptorFactory.fromBitmap(getViewBitmap(view));
165 
166             Bundle bundle = new Bundle();
167             bundle.putSerializable("HOTEL", hotel);
168 
169             OverlayOptions oo = new MarkerOptions().position(ll).icon(markerIcon).zIndex(9).draggable(true).extraInfo(bundle);
170             mBaiduMap.addOverlay(oo);
171         }
172 
173     }
174 
175     @Override
176     protected void onPause() {
177         mMapView.onPause();
178         super.onPause();
179     }
180 
181     @Override
182     protected void onResume() {
183         mMapView.onResume();
184         super.onResume();
185     }
186 
187     @Override
188     protected void onDestroy() {
189         // 退出时销毁定位
190         mLocClient.stop();
191         // 关闭定位图层
192         mBaiduMap.setMyLocationEnabled(false);
193         mMapView.onDestroy();
194         mMapView = null;
195         super.onDestroy();
196     }
197 
198 }

activity代码注释不多，有不明白的地方请自行下载官方Demo来研究。

代码下载地址 http://download.csdn.net/detail/showraining/9058193