集成地圖SDK

國內常用的地圖SDK就是百度和高德了，二者的用法大同小異，可按照官網上的開發指南一步步來。下面是我在集成地圖SDK時遇到的問題說明：
1、點擊基本地圖功能選項，不能打開地圖，彈出“key驗證出錯！請在AndroidManifest.xml文件中檢查key設置的”的紅色字提示。查看日志提示“galaxy lib host missing meta-data,make sure you know the right way to integrate galaxy”
該問題是因為key值對應的簽名與app打包用的簽名不一致。app在開發時與發布時有兩個不同的簽名，開發時用的是ADT默認簽名，查看默認簽名的SHA1值可依次選擇“Window”->“Preferences”->“Android”->“Build SHA1 fingerprint”。app發布時的簽名是密鑰文件的簽名，查看發布簽名的SHA1值可依次選擇“File”->“Export”->“Export Android Application”->“Next”後選擇密鑰文件並輸入密碼與app輸出路徑->在“Certificate fingerprints”下查看SHA1值。
2、百度地圖SDK3.6及以上版本找不到overlayutil包。
這是因為新版SDK的jar包不再包含這部分源碼，得到官方demo的src目錄下獲取源碼加入到開發者自己的工程中，源碼路徑為：BaiduMap_AndroidMapSDK_v3.7.1_Sample\BaiduMapsApiDemo\src\com\baidu\mapapi
3、在一個工程中同時包含了百度地圖和高德地圖的sdk，編譯時報錯“Found duplicate file for APK: assets/lineDashTexture.png”。
這是因為百度和高德的sdk，其jar包存在同名文件“assets/lineDashTexture.png”，所以無法通過編譯。即百度sdk與高德sdk是互斥的，不能同時存在於同個工程中，必須分開來使用。

顯示地圖和定位

對於一個地圖SDK來說，首先要顯示地圖，然後定位到當前城市。

這方面百度地圖和高德地圖的處理代碼差不多，下面是兩種地圖sdk顯示並定位的代碼例子：
百度地圖

	// 以下主要是定位用到的代碼
	private MapView mMapView;
	private BaiduMap mMapLayer;
	private LocationClient mLocClient;
	private boolean isFirstLoc = true;// 是否首次定位

	private void initLocation() {
		mMapView = (MapView) findViewById(R.id.bmapView);
		// 先隱藏地圖，待定位到當前城市時再顯示
		mMapView.setVisibility(View.INVISIBLE);
		mMapLayer = mMapView.getMap();
		mMapLayer.setOnMapClickListener(this);
		// 開啟定位圖層
		mMapLayer.setMyLocationEnabled(true);
		mLocClient = new LocationClient(this);
		// 設置定位監聽器
		mLocClient.registerLocationListener(new MyLocationListenner());
		LocationClientOption option = new LocationClientOption();
		option.setOpenGps(true);// 打開gps
		option.setCoorType("bd09ll"); // 設置坐標類型
		option.setScanSpan(1000);
		option.setIsNeedAddress(true); // 設置true才能獲得詳細的地址信息
		// 設置定位參數
		mLocClient.setLocOption(option);
		// 開始定位
		mLocClient.start();
		 //獲取最近一次的位置
		// mLocClient.getLastKnownLocation();
	}

	public class MyLocationListenner implements BDLocationListener {

		@Override
		public void onReceiveLocation(BDLocation location) {
			// map view 銷毀後不在處理新接收的位置
			if (location == null || mMapView == null) {
				Log.d(TAG, "location is null or mMapView is null");
				return;
			}
			m_latitude = location.getLatitude();
			m_longitude = location.getLongitude();
			String position = String.format("當前位置：%s|%s|%s|%s|%s|%s|%s",
					location.getProvince(), location.getCity(),
					location.getDistrict(), location.getStreet(),
					location.getStreetNumber(), location.getAddrStr(),
					location.getTime());
			loc_position.setText(position);
			MyLocationData locData = new MyLocationData.Builder()
					.accuracy(location.getRadius())
					// 此處設置開發者獲取到的方向信息，順時針0-360
					.direction(100).latitude(m_latitude)
					.longitude(m_longitude).build();
			mMapLayer.setMyLocationData(locData);
			if (isFirstLoc) {
				isFirstLoc = false;
				LatLng ll = new LatLng(m_latitude, m_longitude);
				MapStatusUpdate update = MapStatusUpdateFactory.newLatLngZoom(ll, 14);
				mMapLayer.animateMapStatus(update);
				// 定位到當前城市時再顯示圖層
				mMapView.setVisibility(View.VISIBLE);
			}
		}

		public void onReceivePoi(BDLocation poiLocation) {
		}
	}

高德地圖

	// 以下主要是定位用到的代碼
	private MapView mMapView;
	private AMap mMapLayer;
	private AMapLocationClient mLocClient;
	private boolean isFirstLoc = true;// 是否首次定位

	private void initLocation(Bundle savedInstanceState) {
		mMapView = (MapView) findViewById(R.id.amapView);
		mMapView.onCreate(savedInstanceState);
		// 先隱藏地圖，待定位到當前城市時再顯示
		mMapView.setVisibility(View.INVISIBLE);
		if (mMapLayer == null) {
			mMapLayer = mMapView.getMap();
		}
		mMapLayer.setOnMapClickListener(this);
		// 開啟定位圖層
		mMapLayer.setMyLocationEnabled(true);
		mMapLayer.setMyLocationType(AMap.LOCATION_TYPE_LOCATE);
		mLocClient = new AMapLocationClient(this.getApplicationContext());
		// 設置定位監聽器
		mLocClient.setLocationListener(new MyLocationListenner());
		AMapLocationClientOption option = new AMapLocationClientOption();
		option.setLocationMode(AMapLocationMode.Battery_Saving);
		option.setNeedAddress(true); // 設置true才能獲得詳細的地址信息
		// 設置定位參數
		mLocClient.setLocationOption(option);
		// 開始定位
		mLocClient.startLocation();
		 //獲取最近一次的位置
		// mLocClient.getLastKnownLocation();
	}

	public class MyLocationListenner implements AMapLocationListener {

		@Override
		public void onLocationChanged(AMapLocation location) {
			// map view 銷毀後不在處理新接收的位置
			if (location == null || mMapView == null) {
				Log.d(TAG, "location is null or mMapView is null");
				return;
			}
			m_latitude = location.getLatitude();
			m_longitude = location.getLongitude();
			String position = String.format("當前位置：%s|%s|%s|%s|%s|%s|%s",
					location.getProvince(), location.getCity(),
					location.getDistrict(), location.getStreet(),
					location.getAdCode(), location.getAddress(),
					location.getTime());
			loc_position.setText(position);
			if (isFirstLoc) {
				isFirstLoc = false;
				LatLng ll = new LatLng(m_latitude, m_longitude);
                CameraUpdate update = CameraUpdateFactory.newLatLngZoom(ll, 12);
				mMapLayer.moveCamera(update);
				// 定位到當前城市時再顯示圖層
				mMapView.setVisibility(View.VISIBLE);
			}
		}
	}

POI搜索

POI即地圖注點，它是“Point of Interest”的縮寫，在地圖上標注地點名稱、類別、經度、緯度等信息，是一個帶位置信息的地圖標注。POI搜索是地圖sdk的一個重要應用，根據關鍵字搜索並在地圖上顯示POI結果，這是智能出行的基礎。


下面是使用百度地圖搜索POI的截圖：



下面是兩種地圖sdk進行POI搜索的代碼例子：
百度地圖

	// 以下主要是POI搜索用到的代碼
	private PoiSearch mPoiSearch = null;
	private SuggestionSearch mSuggestionSearch = null;
	private AutoCompleteTextView mKey = null;
	private EditText mScope = null;
	private Button btn_search, btn_nextpage, btn_cleardata;
	private ArrayAdapter sugAdapter = null;
	private int load_Index = 0;

	private void initMap() {
		mPoiSearch = PoiSearch.newInstance();
		mPoiSearch.setOnGetPoiSearchResultListener(this);
		mSuggestionSearch = SuggestionSearch.newInstance();
		mSuggestionSearch.setOnGetSuggestionResultListener(this);
		mScope = (EditText) findViewById(R.id.poi_city);
		mKey = (AutoCompleteTextView) findViewById(R.id.poi_searchkey);
		btn_search = (Button) findViewById(R.id.search);
		btn_nextpage = (Button) findViewById(R.id.map_next_data);
		btn_cleardata = (Button) findViewById(R.id.map_clear_data);
		btn_search.setOnClickListener(this);
		btn_nextpage.setOnClickListener(this);
		btn_cleardata.setOnClickListener(this);
		sugAdapter = new ArrayAdapter(this, R.layout.spinner_dropdown_item);
		mKey.setAdapter(sugAdapter);

		// 當輸入關鍵字變化時，動態更新建議列表
		mKey.addTextChangedListener(new TextWatcher() {

			@Override
			public void afterTextChanged(Editable arg0) {
			}

			@Override
			public void beforeTextChanged(CharSequence arg0, int arg1,
					int arg2, int arg3) {
			}

			@Override
			public void onTextChanged(CharSequence cs, int arg1, int arg2,
					int arg3) {
				if (cs.length() <= 0) {
					return;
				}
				String city = mScope.getText().toString();
				// 使用建議搜索服務獲取建議列表，結果在onGetSuggestionResult中更新
				mSuggestionSearch
						.requestSuggestion((new SuggestionSearchOption())
								.keyword(cs.toString()).city(city));
			}
		});
	}

	@Override
	public void onGetSuggestionResult(SuggestionResult res) {
		if (res == null || res.getAllSuggestions() == null) {
			return;
		} else {
			sugAdapter.clear();
			for (SuggestionResult.SuggestionInfo info : res.getAllSuggestions()) {
				if (info.key != null) {
					sugAdapter.add(info.key);
				}
			}
			sugAdapter.notifyDataSetChanged();
		}
	}

	// 影響搜索按鈕點擊事件
	public void searchButtonProcess(View v) {
		Log.d(TAG, "editCity=" + mScope.getText().toString()
				+ ", editSearchKey=" + mKey.getText().toString()
				+ ", load_Index=" + load_Index);
		String keyword = mKey.getText().toString();
		if (search_method == SEARCH_CITY) {
			String city = mScope.getText().toString();
			mPoiSearch.searchInCity((new PoiCitySearchOption()).city(city)
					.keyword(keyword).pageNum(load_Index));
		} else if (search_method == SEARCH_NEARBY) {
			LatLng position = new LatLng(m_latitude, m_longitude);
			int radius = Integer.parseInt(mScope.getText().toString());
			mPoiSearch.searchNearby((new PoiNearbySearchOption())
					.location(position).keyword(keyword).radius(radius)
					.pageNum(load_Index));
		}
	}

	public void goToNextPage(View v) {
		load_Index++;
		searchButtonProcess(null);
	}

	public void onGetPoiResult(PoiResult result) {
		if (result == null
				|| result.error == SearchResult.ERRORNO.RESULT_NOT_FOUND) {
			Toast.makeText(this, "未找到結果", Toast.LENGTH_LONG).show();
			return;
		} else if (result.error == SearchResult.ERRORNO.NO_ERROR) {
			mMapLayer.clear();
			PoiOverlay overlay = new MyPoiOverlay(mMapLayer);
			mMapLayer.setOnMarkerClickListener(overlay);
			List poiList = result.getAllPoi();
			overlay.setData(result);
			overlay.addToMap();
			overlay.zoomToSpan();
//			for (PoiInfo poi : poiList) {
//			String detail = String.format(
//					"uid=%s,city=%s,name=%s,phone=%s, address=%s", poi.uid,
//					poi.city, poi.name, poi.phoneNum, poi.address);
//			Log.d(TAG, detail); // 坐標為poi.location（LatLng結構）
//			}
		} else if (result.error == SearchResult.ERRORNO.AMBIGUOUS_KEYWORD) {
			// 當輸入關鍵字在本市沒有找到，但在其他城市找到時，返回包含該關鍵字信息的城市列表
			String strInfo = "在";
			for (CityInfo cityInfo : result.getSuggestCityList()) {
				strInfo += cityInfo.city + ",";
			}
			strInfo += "找到結果";
			Toast.makeText(this, strInfo, Toast.LENGTH_LONG).show();
		}
	}

	public void onGetPoiDetailResult(PoiDetailResult result) {
		if (result.error != SearchResult.ERRORNO.NO_ERROR) {
			Toast.makeText(this, "抱歉，未找到結果", Toast.LENGTH_SHORT).show();
		} else {
			Log.d(TAG,
					"name=" + result.getName() + ",address="
							+ result.getAddress() + ",detail_url="
							+ result.getDetailUrl() + ",shop_hours="
							+ result.getShopHours() + ",telephone="
							+ result.getTelephone() + ",price="
							+ result.getPrice() + ",type=" + result.getType()
							+ ",tag=" + result.getTag());
			Toast.makeText(this, result.getName() + ": " + result.getAddress(),
					Toast.LENGTH_SHORT).show();
		}
	}

	private class MyPoiOverlay extends PoiOverlay {

		public MyPoiOverlay(BaiduMap baiduMap) {
			super(baiduMap);
		}

		@Override
		public boolean onPoiClick(int index) {
			super.onPoiClick(index);
			PoiInfo poi = getPoiResult().getAllPoi().get(index);
			mPoiSearch.searchPoiDetail((new PoiDetailSearchOption()).poiUid(poi.uid));
			return true;
		}
	}

高德地圖

	// 以下主要是POI搜索用到的代碼
	private PoiSearch mPoiSearch = null;
	private AutoCompleteTextView mKey = null;
	private EditText mScope = null;
	private Button btn_search, btn_nextpage, btn_cleardata;
	private ArrayAdapter sugAdapter = null;
	private int load_Index = 0;

	private void initMap() {
		mScope = (EditText) findViewById(R.id.poi_city);
		mKey = (AutoCompleteTextView) findViewById(R.id.poi_searchkey);
		btn_search = (Button) findViewById(R.id.search);
		btn_nextpage = (Button) findViewById(R.id.map_next_data);
		btn_cleardata = (Button) findViewById(R.id.map_clear_data);
		btn_search.setOnClickListener(this);
		btn_nextpage.setOnClickListener(this);
		btn_cleardata.setOnClickListener(this);
		sugAdapter = new ArrayAdapter(this, R.layout.spinner_dropdown_item);
		mKey.setAdapter(sugAdapter);

		// 當輸入關鍵字變化時，動態更新建議列表
		mKey.addTextChangedListener(new TextWatcher() {

			@Override
			public void afterTextChanged(Editable arg0) {
			}

			@Override
			public void beforeTextChanged(CharSequence arg0, int arg1,
					int arg2, int arg3) {
			}

			@Override
			public void onTextChanged(CharSequence cs, int arg1, int arg2,
					int arg3) {
				if (cs.length() <= 0) {
					return;
				}
				String city = mScope.getText().toString();
				// 使用建議搜索服務獲取建議列表，結果在onGetInputtips中更新
			    InputtipsQuery inputquery = new InputtipsQuery(cs.toString(), city);
			    Inputtips inputTips = new Inputtips(GaodeActivity.this, inputquery);
			    inputTips.setInputtipsListener(GaodeActivity.this);
			    inputTips.requestInputtipsAsyn();
			}
		});
	}

	@Override
	public void onGetInputtips(List tipList, int rCode) {
		if (rCode != 1000) {
			Toast.makeText(this, "推薦文字錯誤代碼是"+rCode, Toast.LENGTH_LONG).show();
		} else {
			sugAdapter.clear();
			for (Tip info : tipList) {
				if (info.getName() != null) {
					sugAdapter.add(info.getName());
				}
			}
			sugAdapter.notifyDataSetChanged();
		}
	}

	// 影響搜索按鈕點擊事件
	public void searchButtonProcess(View v) {
		Log.d(TAG, "editCity=" + mScope.getText().toString()
				+ ", editSearchKey=" + mKey.getText().toString()
				+ ", load_Index=" + load_Index);
		String keyword = mKey.getText().toString();
		if (search_method == SEARCH_CITY) {
			String city = mScope.getText().toString();
			PoiSearch.Query query = new PoiSearch.Query(keyword, null, city);
			query.setPageSize(10);
			query.setPageNum(load_Index);
			mPoiSearch = new PoiSearch(this, query);
			mPoiSearch.setOnPoiSearchListener(this);
			mPoiSearch.searchPOIAsyn();
		} else if (search_method == SEARCH_NEARBY) {
			LatLonPoint position = new LatLonPoint(m_latitude, m_longitude);
			int radius = Integer.parseInt(mScope.getText().toString());
			PoiSearch.Query query = new PoiSearch.Query(keyword, null, "福州");
			query.setPageSize(10);
			query.setPageNum(load_Index);
			mPoiSearch = new PoiSearch(this, query);
			SearchBound bound = new SearchBound(position, radius);
			mPoiSearch.setBound(bound);
			mPoiSearch.setOnPoiSearchListener(this);
			mPoiSearch.searchPOIAsyn();
		}
	}

	public void goToNextPage(View v) {
		load_Index++;
		searchButtonProcess(null);
	}

	@Override
	public void onPoiSearched(PoiResult result, int rCode) {
		if (rCode != 1000) {
			Toast.makeText(this, "POI錯誤代碼是"+rCode, Toast.LENGTH_LONG).show();
		} else if (result == null || result.getQuery() == null) {
			Toast.makeText(this, "未找到結果", Toast.LENGTH_LONG).show();
			return;
		} else {
			mMapLayer.clear();
			List poiList = result.getPois();
			// 當搜索不到poiitem數據時，會返回含有搜索關鍵字的城市信息
			List suggestionCities = result.getSearchSuggestionCitys();
			if (poiList!=null && poiList.size()>0) {
				PoiOverlay poiOverlay = new PoiOverlay(mMapLayer, poiList);
				//從地圖上移除原POI信息
				poiOverlay.removeFromMap();
				//往地圖添加新POI信息
				poiOverlay.addToMap();
				poiOverlay.zoomToSpan();
				//給POI添加監聽器。在點擊POI時提示POI信息
				mMapLayer.setOnMarkerClickListener(new OnMarkerClickListener() {
					@Override
					public boolean onMarkerClick(Marker marker) {
						marker.showInfoWindow();
						return true;
					}
				});
//				for (PoiItem poi : poiList) {
//					String detail = String.format(
//							"uid=%s,city=%s,name=%s,phone=%s, address=%s", poi.getPoiId(),
//							poi.getCityName(), poi.getTitle(), poi.getTel(), poi.getAdName());
//					Log.d(TAG, detail); // 坐標為poi.location（LatLng結構）
//				}
			} else if (suggestionCities != null && suggestionCities.size() > 0) {
				String infomation = "推薦城市\n";
				for (int i = 0; i < suggestionCities.size(); i++) {
					SuggestionCity city = suggestionCities.get(i);
					infomation += "城市名稱:" + city.getCityName() + "城市區號:"
							+ city.getCityCode() + "城市編碼:"
							+ city.getAdCode() + "\n";
				}
				Toast.makeText(this, infomation, Toast.LENGTH_LONG).show();
			} else {
				Toast.makeText(this, "結果記錄數為0", Toast.LENGTH_LONG).show();
			}
			return;
		}
	}

	@Override
	public void onPoiItemSearched(PoiItem paramPoiItem, int paramInt) {
		// TODO Auto-generated method stub
		
	}

測距、測面積

測量距離和測量面積是地圖sdk的又一個應用，除了在地圖上添加標注之外，就是要用到數學的兩個公式。
其中測距用的是勾股定理（又名商高定理）：勾股定理是一個基本的幾何定理：一個直角三角形，兩直角邊的平方和等於斜邊的平方。如果直角三角形兩直角邊為a和b，斜邊為c，那麼a*a+b*b=c*c
測面積用的是海倫公式（又名秦九韶公式）：海倫公式是利用三角形的三個邊長直接求三角形面積的公式，表達式為：S=√p(p-a)(p-b)(p-c)。基於海倫公式，可以推導出根據多邊形各邊長求多邊形面積的公式，即S = 0.5 * ( (x0*y1-x1*y0) + (x1*y2-x2*y1) + ... + (xn*y0-x0*yn) )


兩種地圖sdk在測量上的數學原理是一樣的，只在添加地圖標注上有些小差異，下面是使用高德地圖進行測量的截圖：



下面是兩種地圖sdk進行測量的代碼例子：
百度地圖

	// 下面是在地圖上添加繪圖操作
	private static int lineColor = 0x55FF0000;
	private static int arcColor = 0xbb00FFFF;
	private static int textColor = 0x990000FF;
	private static int polygonColor = 0x77FFFF00;
	private static int radius = 100;
	private ArrayList posArray = new ArrayList();
	boolean is_polygon = false;

	private void addDot(LatLng pos) {
		if (is_polygon == true && posArray.size() > 1
				&& MapUtil.isInsidePolygon(pos, posArray) == true) {
			Log.d(TAG, "isInsidePolygon");
			LatLng centerPos = MapUtil.getCenterPos(posArray);
			OverlayOptions ooText = new TextOptions().bgColor(0x00ffffff)
					.fontSize(26).fontColor(textColor).text("標題")// .rotate(-30)
					.position(centerPos);
			mMapLayer.addOverlay(ooText);
			return;
		}
		if (is_polygon == true) {
			Log.d(TAG, "is_polygon == true");
			posArray.clear();
			is_polygon = false;
		}
		boolean is_first = false;
		LatLng thisPos = pos;
		if (posArray.size() > 0) {
			LatLng firstPos = posArray.get(0);
			int distance = (int) Math.round(MapUtil.getShortDistance(
					thisPos.longitude, thisPos.latitude, firstPos.longitude,
					firstPos.latitude));
			//多次點擊起點，要忽略之
			if (posArray.size()==1 && distance<=0) {
				return;
			} else if (posArray.size() > 1) {
				LatLng lastPos = posArray.get(posArray.size()-1);
				int lastDistance = (int) Math.round(MapUtil.getShortDistance(
						thisPos.longitude, thisPos.latitude, lastPos.longitude,
						lastPos.latitude));
				//重復響應當前位置的點擊，要忽略之
				if (lastDistance <= 0) {
					return;
				}
			}
			if (distance < radius * 2) {
				thisPos = firstPos;
				is_first = true;
			}
			Log.d(TAG, "distance="+distance+", radius="+radius+", is_first="+is_first);

			// 畫直線
			LatLng lastPos = posArray.get(posArray.size() - 1);
			List points = new ArrayList();
			points.add(lastPos);
			points.add(thisPos);
			OverlayOptions ooPolyline = new PolylineOptions().width(2)
					.color(lineColor).points(points);
			mMapLayer.addOverlay(ooPolyline);

			// 下面計算兩點之間距離
			distance = (int) Math.round(MapUtil.getShortDistance(
					thisPos.longitude, thisPos.latitude, lastPos.longitude,
					lastPos.latitude));
			String disText = "";
			if (distance > 1000) {
				disText = Math.round(distance * 10 / 1000) / 10d + "公裡";
			} else {
				disText = distance + "米";
			}
			LatLng llText = new LatLng(
					(thisPos.latitude + lastPos.latitude) / 2,
					(thisPos.longitude + lastPos.longitude) / 2);
			OverlayOptions ooText = new TextOptions().bgColor(0x00ffffff)
					.fontSize(24).fontColor(textColor).text(disText)// .rotate(-30)
					.position(llText);
			mMapLayer.addOverlay(ooText);
		}
		if (is_first != true) {
			// 畫圓圈
			OverlayOptions ooCircle = new CircleOptions().fillColor(lineColor)
					.center(thisPos).stroke(new Stroke(2, 0xAAFF0000)).radius(radius);
			mMapLayer.addOverlay(ooCircle);
			// 畫圖片標記
			BitmapDescriptor bitmapDesc = BitmapDescriptorFactory
					.fromResource(R.drawable.icon_geo);
			OverlayOptions ooMarker = new MarkerOptions().draggable(false)
					.visible(true).icon(bitmapDesc).position(thisPos);
			mMapLayer.addOverlay(ooMarker);
			mMapLayer.setOnMarkerClickListener(new OnMarkerClickListener() {
				@Override
				public boolean onMarkerClick(Marker marker) {
					LatLng markPos = marker.getPosition();
					addDot(markPos);
					return true;
				}
			});
		} else {
			Log.d(TAG, "posArray.size()="+posArray.size());
			//可能存在地圖與標記同時響應點擊事件的情況
			if (posArray.size() < 3) {
				posArray.clear();
				is_polygon = false;
				return;
			}
			// 畫多邊形
			OverlayOptions ooPolygon = new PolygonOptions().points(posArray)
					.stroke(new Stroke(1, 0xFF00FF00))
					.fillColor(polygonColor);
			mMapLayer.addOverlay(ooPolygon);
			is_polygon = true;

			// 下面計算多邊形的面積
			LatLng centerPos = MapUtil.getCenterPos(posArray);
			double area = Math.round(MapUtil.getArea(posArray));
			String areaText = "";
			if (area > 1000000) {
				areaText = Math.round(area * 100 / 1000000) / 100d + "平方公裡";
			} else {
				areaText = (int) area + "平方米";
			}
			OverlayOptions ooText = new TextOptions().bgColor(0x00ffffff)
					.fontSize(26).fontColor(textColor).text(areaText)// .rotate(-30)
					.position(centerPos);
			mMapLayer.addOverlay(ooText);
		}
		posArray.add(thisPos);
		if (posArray.size() >= 3) {
			// 畫弧線
			OverlayOptions ooArc = new ArcOptions()
					.color(arcColor)
					.width(2)
					.points(posArray.get(posArray.size() - 1),
							posArray.get(posArray.size() - 2),
							posArray.get(posArray.size() - 3));
			mMapLayer.addOverlay(ooArc);
		}
	}

	@Override
	public void onMapClick(LatLng arg0) {
		addDot(arg0);
	}

	@Override
	public boolean onMapPoiClick(MapPoi arg0) {
		addDot(arg0.getPosition());
		return false;
	}

高德地圖

	// 下面是在地圖上添加繪圖操作
	private static int lineColor = 0x55FF0000;
	private static int arcColor = 0xbb00FFFF;
	private static int textColor = 0x990000FF;
	private static int polygonColor = 0x77FFFF00;
	private static int radius = 100;
	private ArrayList posArray = new ArrayList();
	boolean is_polygon = false;

	private void addDot(LatLng pos) {
		if (is_polygon == true && posArray.size() > 1
				&& MapUtil.isInsidePolygon(pos, posArray) == true) {
			Log.d(TAG, "isInsidePolygon");
			LatLng centerPos = MapUtil.getCenterPos(posArray);
			TextOptions ooText = new TextOptions().backgroundColor(0x00ffffff)
					.fontSize(26).fontColor(textColor).text("標題")// .rotate(-30)
					.position(centerPos);
			mMapLayer.addText(ooText);
			return;
		}
		if (is_polygon == true) {
			Log.d(TAG, "is_polygon == true");
			posArray.clear();
			is_polygon = false;
		}
		boolean is_first = false;
		LatLng thisPos = pos;
		if (posArray.size() > 0) {
			LatLng firstPos = posArray.get(0);
			int distance = (int) Math.round(MapUtil.getShortDistance(
					thisPos.longitude, thisPos.latitude, firstPos.longitude,
					firstPos.latitude));
			//多次點擊起點，要忽略之
			if (posArray.size()==1 && distance<=0) {
				return;
			} else if (posArray.size() > 1) {
				LatLng lastPos = posArray.get(posArray.size()-1);
				int lastDistance = (int) Math.round(MapUtil.getShortDistance(
						thisPos.longitude, thisPos.latitude, lastPos.longitude,
						lastPos.latitude));
				//重復響應當前位置的點擊，要忽略之
				if (lastDistance <= 0) {
					return;
				}
			}
			if (distance < radius * 2) {
				thisPos = firstPos;
				is_first = true;
			}
			Log.d(TAG, "distance="+distance+", radius="+radius+", is_first="+is_first);

			// 畫直線
			LatLng lastPos = posArray.get(posArray.size() - 1);
			List points = new ArrayList();
			points.add(lastPos);
			points.add(thisPos);
			PolylineOptions ooPolyline = new PolylineOptions().width(2)
					.color(lineColor).addAll(points);
			mMapLayer.addPolyline(ooPolyline);

			// 下面計算兩點之間距離
			distance = (int) Math.round(MapUtil.getShortDistance(
					thisPos.longitude, thisPos.latitude, lastPos.longitude,
					lastPos.latitude));
			String disText = "";
			if (distance > 1000) {
				disText = Math.round(distance * 10 / 1000) / 10d + "公裡";
			} else {
				disText = distance + "米";
			}
			LatLng llText = new LatLng(
					(thisPos.latitude + lastPos.latitude) / 2,
					(thisPos.longitude + lastPos.longitude) / 2);
			TextOptions ooText = new TextOptions().backgroundColor(0x00ffffff)
					.fontSize(24).fontColor(textColor).text(disText)// .rotate(-30)
					.position(llText);
			mMapLayer.addText(ooText);
		}
		if (is_first != true) {
			// 畫圓圈
			CircleOptions ooCircle = new CircleOptions().fillColor(lineColor)
					.center(thisPos).strokeWidth(2).strokeColor(0xAAFF0000).radius(radius);
			mMapLayer.addCircle(ooCircle);
			// 畫圖片標記
			BitmapDescriptor bitmapDesc = BitmapDescriptorFactory
					.fromResource(R.drawable.icon_geo);
			MarkerOptions ooMarker = new MarkerOptions().draggable(false)
					.visible(true).icon(bitmapDesc).position(thisPos);
			mMapLayer.addMarker(ooMarker);
			mMapLayer.setOnMarkerClickListener(new OnMarkerClickListener() {
				@Override
				public boolean onMarkerClick(Marker marker) {
					LatLng markPos = marker.getPosition();
					addDot(markPos);
					marker.showInfoWindow();
					return true;
				}
			});
		} else {
			Log.d(TAG, "posArray.size()="+posArray.size());
			//可能存在地圖與標記同時響應點擊事件的情況
			if (posArray.size() < 3) {
				posArray.clear();
				is_polygon = false;
				return;
			}
			// 畫多邊形
			PolygonOptions ooPolygon = new PolygonOptions().addAll(posArray)
					.strokeColor(0xFF00FF00).strokeWidth(1)
					.fillColor(polygonColor);
			mMapLayer.addPolygon(ooPolygon);
			is_polygon = true;

			// 下面計算多邊形的面積
			LatLng centerPos = MapUtil.getCenterPos(posArray);
			double area = Math.round(MapUtil.getArea(posArray));
			String areaText = "";
			if (area > 1000000) {
				areaText = Math.round(area * 100 / 1000000) / 100d + "平方公裡";
			} else {
				areaText = (int) area + "平方米";
			}
			TextOptions ooText = new TextOptions().backgroundColor(0x00ffffff)
					.fontSize(26).fontColor(textColor).text(areaText)// .rotate(-30)
					.position(centerPos);
			mMapLayer.addText(ooText);
		}
		posArray.add(thisPos);
		if (posArray.size() >= 3) {
			// 畫弧線
			ArcOptions ooArc = new ArcOptions()
					.strokeColor(arcColor)
					.strokeWidth(2)
					.point(posArray.get(posArray.size() - 1),
							posArray.get(posArray.size() - 2),
							posArray.get(posArray.size() - 3));
			mMapLayer.addArc(ooArc);
		}
	}

	@Override
	public void onMapClick(LatLng arg0) {
		addDot(arg0);
	}