[Baidu map development 4] implementation of basic Baidu map operations

Preface:

[Baidu map development 4] Baidu map basic operation functions to explain (blog address: http://blog.csdn.net/developer_jiangqq), reprint please note.

Author: hmjiangqq

Email: jiangqqlmj@163.com

In the previous article, we learned about [Baidu map development 3] Baidu map UI control function (click to jump). Today, we will continue to look at the implementation of some basic operation functions of Baidu map;

(1) Basic Introduction:

Some basic operations and control of Baidu map include map scaling, rotation, overlooking, single-click, long-press, and other control events. To implement the preceding three functions, MapController class and single-click, mapView's listening event processing interface MKMapTouchListener is used for long-press events.

(2) control class, interface Basic Introduction 1: MapController: Map Operation Controller. Today we mainly use the following methods:

①: Public float setZoom (float zoomLevel): sets the zoom level of the map. The value range is [3, 19].

②: Public void setRotation (int rotate): sets the Rotation Angle of the map.

③: Public void setOverlooking (int voidlook): sets the view angle of a map.

2: MKMapTouchListener: the map Click Event listener interface. The main methods are as follows:

①: Void onMapClick (GeoPoint point): Click an event on the map and call back the coordinates of the clicked map.

②: Void onMapDoubleClick (GeoPoint point): double-click the map event, and calls back the coordinates of the double-click map.

③: Void onMapLongClick (GeoPoint point): Specifies the coordinates of the long-pressed map.

(3) how to use the event listener:

You only need to register the MKMapTouchListener listener in the MapView object, click it, double-click it, and long-Press the event method. The implementation method is as follows:

/*** Set the map Click Event listener */mapTouchListener = new MKMapTouchListener () {@ Overridepublic void onMapClick (GeoPoint point) {touchType = "click"; currentPt = point; updateMapState () ;}@ Overridepublic void onMapDoubleClick (GeoPoint point) {touchType = "double-click"; currentPt = point; updateMapState () ;}@ Overridepublic void onMapLongClick (GeoPoint point) {touchType = "Long press"; currentPt = point; updateMapState () ;}}; // register the mMapView event for the map. regMapTouchListner (mapTouchListener );

(4) let's take a look at the demo example in Baidu map SDK (the comments in the Code have been added in detail on this basis)

1: MyApplication. java: Set BMapManager global variables and verify the key. The Code is as follows:

Package com. ztt. baidumap. ui; import android. app. application; import android. content. context; import android. util. log; import android. widget. toast; import com. baidu. mapapi. BMapManager; import com. baidu. mapapi. MKGeneralListener; import com. baidu. mapapi. map. MKEvent;/*** Custom Application for key identification and verification (using a singleton) * @ author Jiangqq * @ time 2014/03/15 */public class MyApplication extends Application {public static MyApplication instance = null; BMapManager mBMapManager = null; public boolean m_bKeyRight = true; public static final String strKey = "vUAGbPwLpolIqiwWisnQPeIE"; // public static MyApplication getInstance () applied for on the Baidu map Official Website () {return instance;} @ Overridepublic void onCreate () {super. onCreate (); instance = this; // initialize and verify the initEngineManager (this) when the APP starts );} /*** verify key * @ param pContext */private void initEngineM Anager (Context pContext) {if (mBMapManager = null) {mBMapManager = new BMapManager (pContext);} if (! MBMapManager. init (strKey, new MyGeneralListener () {Toast. makeText (MyApplication. getInstance (), "BMapManager initialization error! ", Toast. LENGTH_LONG ). show () ;}// common event listening, used to handle common network errors, authorization verification errors, and other static class MyGeneralListener implements MKGeneralListener {@ Override public void onGetNetworkState (int iError) {if (iError = MKEvent. ERROR_NETWORK_CONNECT) {Toast. makeText (MyApplication. getInstance (), "your network has an error! ", Toast. LENGTH_LONG). show ();} else if (iError = MKEvent. ERROR_NETWORK_DATA) {Toast. makeText (MyApplication. getInstance ()," enter the correct search conditions! ", Toast. LENGTH_LONG ). show ();} else {Log. d ("zttjiangqq", "iError =" + iError );}//...} @ Override public void onGetPermissionState (int iError) {// a non-zero value indicates that the key verification fails if (iError! = 0) {// Authorization Key error: Toast. makeText (MyApplication. getInstance (), "Please go to DemoApplication. enter the correct authorization Key in the java file and check whether your network connection is normal! Error: "+ iError, Toast. LENGTH_LONG ). show (); MyApplication. getInstance (). m_bKeyRight = false;} else {MyApplication. getInstance (). m_bKeyRight = true; Toast. makeText (MyApplication. getInstance (), "key Authentication successful", Toast. LENGTH_LONG ). show ();}}}}

2: Layout file:

<? Xml version = "1.0" encoding = "UTF-8"?> <LinearLayout xmlns: android = "http://schemas.android.com/apk/res/android" android: orientation = "vertical" android: layout_width = "fill_parent" android: layout_height = "fill_parent"> <LinearLayout android: orientation = "horizontal" android: layout_width = "fill_parent" android: layout_height = "50dip"> <Button android: id = "@ + id/zoombutton" android: layout_width = "fill_parent" android: layout_height = "wrap_content" android: layout_weight = "1" android: background = "@ drawable/button_style" android: text = "zoom"/> <EditText android: id = "@ + id/zoomlevel" android: layout_width = "fill_parent" android: layout_height = "wrap_content" android: layout_weight = "1" android: text = "10"/> <Button android: id = "@ + id/rotatebutton" android: layout_width = "fill_parent" android: layout_height = "wrap_content" android: layout_weight = "1" android: background = "@ drawable/button_style" android: text = "Rotate"/> <EditText android: id = "@ + id/rotateangle" android: text = "90" android: layout_width = "fill_parent" android: layout_height = "wrap_content" android: layout_weight = "1"/> <Button android: id = "@ + id/overlookbutton" android: layout_width = "fill_parent" android: layout_height = "wrap_content" android: layout_weight = "1" android: background = "@ drawable/button_style" android: text = "overlooking"/> <EditText android: id = "@ + id/overlookangle" android: text = "-30" android: layout_width = "fill_parent" android: layout_height = "wrap_content" android: layout_weight = "1"/> </LinearLayout> <TextView android: id = "@ + id/state" android: text = "click, long press, and double-click a map to get the longitude and latitude and MAP status" android: layout_width = "fill_parent" android: layout_height = "wrap_content" android: lines = "3"/> <RelativeLayout android: orientation = "vertical" android: layout_width = "fill_parent" android: layout_height = "fill_parent"> <com. baidu. mapapi. map. mapView android: id = "@ + id/bmapView" android: layout_width = "fill_parent" android: layout_height = "fill_parent" android: clickable = "true"/> <Button android: id = "@ + id/savescreen" android: layout_width = "wrap_content" android: layout_height = "wrap_content" android: layout_alignParentTop = "true" android: layout_alignParentRight = "true" android: layout_marginTop = "10dip" android: background = "@ drawable/button_style" android: text = ""/> </RelativeLayout> </LinearLayout>

3: function implementation Activity code:

Package com. ztt. baidumap. ui; import java. io. file; import java. io. fileNotFoundException; import java. io. fileOutputStream; import java. io. IOException; import android. app. activity; import android. graphics. bitmap; import android. OS. bundle; import android. view. view; import android. view. view. onClickListener; import android. widget. button; import android. widget. editText; import android. widget. textView; import android. w Idget. toast; import com. baidu. mapapi. BMapManager; import com. baidu. mapapi. map. MKMapTouchListener; import com. baidu. mapapi. map. MKMapViewListener; import com. baidu. mapapi. map. mapController; import com. baidu. mapapi. map. mapPoi; import com. baidu. mapapi. map. mapView; import com. baidu. platform. comapi. basestruct. geoPoint;/*** demonstrate map scaling, rotation, and view control */public class MapControlDemo extends Activity {/*** MapView is the main map control */p Rivate MapView mMapView = null;/*** map control using MapController */private MapController mMapController = null;/*** MKMapViewListener is used to process map Event Callback */MKMapViewListener mMapListener = null; /*** capture screen coordinates */MKMapTouchListener mapTouchListener = null;/*** click the current vertex */private GeoPoint currentPt = null; /*** control Button */private Button zoomButton = null; // scale private Button rotateButton = null; // rotate private Button overl OokButton = null; // overlooking private Button saveScreenButton = null; // *****/private String touchType = null; /*** panel used to display the MAP status */private TextView mStateBar = null; @ Override public void onCreate (Bundle savedInstanceState) {super. onCreate (savedInstanceState);/*** before using the map sdk, initialize BMapManager. * BMapManager is global and can be shared by multiple mapviews. It needs to be created before the map module is created. * If the map module is still in use, BMapManager should not destroy */MyApplication app = (MyApplication) this. getApplication (); if (app. mBMapManager = null) {app. mBMapManager = new BMapManager (getApplicationContext ();/*** initialize BMapManager */app if BMapManager is not initialized. mBMapManager. init (MyApplication. strKey, new MyApplication. myGeneralListener ();}/*** because MapView is initialized in setContentView (), it must be */setContentView (R. layout. activity_mapcontrol); mMapView = (MapView) findViewByI D (R. id. bmapView);/*** get map controller */mMapController = mMapView. getController ();/*** sets whether the map responds to the click event. */mMapController. enableClick (true);/*** set the map zoom level */mMapController. setZoom (12); mStateBar = (TextView) findViewById (R. id. state);/*** initialize the map event listener */initListener ();/*** move the map to Tiananmen * use Baidu longitude and latitude coordinates, you can use http://api.map.baidu.com/lbsapi/getpoint/index.htmlto query geographic coordinates * if you need to display the location of other coordinate systems on baidu map, please send an email to mapapi @ baidu. Com application coordinate conversion interface */double cLat = 39.945; double cLon = 116.404; GeoPoint p = new GeoPoint (int) (cLat * 1E6), (int) (cLon * 1E6); mMapController. setCenter (p);}/*** add listener event */private void initListener () {/*** set map Click Event listener */mapTouchListener = new MKMapTouchListener () {@ Overridepublic void onMapClick (GeoPoint point) {touchType = "click"; currentPt = point; updateMapState () ;}@ Overridepublic void onMapDoub LeClick (GeoPoint point) {touchType = "double-click"; currentPt = point; updateMapState () ;}@ Overridepublic void onMapLongClick (GeoPoint point) {touchType = "Long press"; currentPt = point; updateMapState () ;}}; // register the mMapView event for the map. regMapTouchListner (mapTouchListener);/*** set map event listening */mMapListener = new MKMapViewListener () {@ Overridepublic void onMapMoveFinish () {/*** callback for Processing Map movement completed here * after scaling and translation operations are completed, this callback is triggered */updateMapState () ;}@ Overridepublic void onClickMapPoi (MapPoi mapPoiInfo) {/*** process the basemap poi click event here * display the basemap poi name and move it to this point * set: mMapController. enableClick (true); this callback can be triggered **/} @ Overridepublic void onGetCurrentMap (Bitmap B) {/*** when mMapView is called. after getCurrentMap (), this callback will be triggered * can be saved to the storage device */File file = new File ("/mnt/sdcard/test.png"); FileOutputStream out; try {out = new FileOutputStream (file); if (B. compress (Bitmap. compressFor Mat. PNG, 70, out) {out. flush (); out. close ();} Toast. makeText (MapControlDemo. this, "screen succeeded, image exists:" + file. toString (), Toast. LENGTH_SHORT ). show ();} catch (FileNotFoundException e) {e. printStackTrace ();} catch (IOException e) {e. printStackTrace () ;}@ Overridepublic void onMapAnimationFinish () {/*** after the map completes the animation-carrying operation (for example, animationTo, this callback is triggered */updateMapState () ;}@ Overridepublic void onMapLoadFinish (){ // TODO Auto-generated method stub }}; mMapView. regMapViewListener (MyApplication. getInstance (). mBMapManager, mMapListener);/*** set the Button listener */zoomButton = (Button) findViewById (R. id. zoombutton); rotateButton = (Button) findViewById (R. id. rotatebutton); overlookButton = (Button) findViewById (R. id. overlookbutton); saveScreenButton = (Button) findViewById (R. id. savescreen); OnClickListener onClickListener = new OnCl IckListener () {@ Overridepublic void onClick (View view) {if (view. equals (zoomButton) {perfomZoom ();} else if (view. equals (rotateButton) {perfomRotate ();} else if (view. equals (overlookButton) {perfomOverlook ();} else if (view. equals (saveScreenButton) {//, save the image mMapView in MKMapViewListener. getCurrentMap (); Toast. makeText (MapControlDemo. this, "screenshots... ", Toast. LENGTH_SHORT ). show () ;}updatemapstate ();} }; ZoomButton. setOnClickListener (onClickListener); rotateButton. setOnClickListener (onClickListener); overlookButton. setOnClickListener (onClickListener); saveScreenButton. setOnClickListener (onClickListener);}/*** process scaling * sdk scaling level range: [3.0, 19.0] */private void perfomZoom () {EditText t = (EditText) findViewById (R. id. zoomlevel); try {float zoomLevel = Float. parseFloat (t. getText (). toString (); // sets the map zoom level MMapController. setZoom (zoomLevel);} catch (NumberFormatException e) {Toast. makeText (this, "enter the correct zoom level", Toast. LENGTH_SHORT ). show () ;}/ *** handle rotation * Rotation Angle Range:-180 ~ 180, unit: degrees counter-clockwise rotation */private void perfomRotate () {EditText t = (EditText) findViewById (R. id. rotateangle); try {int rotateAngle = Integer. parseInt (t. getText (). toString (); // sets the map Rotation Angle mMapController. setRotation (rotateAngle);} catch (NumberFormatException e) {Toast. makeText (this, "enter the correct Rotation Angle", Toast. LENGTH_SHORT ). show () ;}/ *** process the top-down list *. The top-down range is-45 ~ 0, unit: Degree */private void perfomOverlook () {EditText t = (EditText) findViewById (R. id. overlookangle); try {int overlookAngle = Integer. parseInt (t. getText (). toString (); // you can specify a map to look down at mMapController. setOverlooking (overlookAngle);} catch (NumberFormatException e) {Toast. makeText (this, "enter the correct corner", Toast. LENGTH_SHORT ). show () ;}/ *** update MAP status display panel */private void updateMapState () {if (mStateBar = null) {return;} String state = ""; if (currentPt = null) {state = "click, long press, double-click map to get latitude and longitude and MAP status";} else {state = String. format (touchType + ", current longitude: % f current latitude: % f", currentPt. getLongitudeE6 () * 1E-6, currentPt. getLatitudeE6 () * 1E-6);} state + = "\ n"; state + = String. format ("zoom level = %. 1f rotate angle = % d overlaylook angle = % d ", mMapView. getZoomLevel (), mMapView. getMapRotation (), mMapView. getMapOverlooking (); mStateBar. setText (state) ;}@ Override protected void onPause () {/*** the life cycle of MapView is synchronized with the Activity. MapView must be called when the activity is suspended. onPause () */mMapView. onPause (); super. onPause () ;}@ Override protected void onResume () {/*** the life cycle of MapView is synchronized with the Activity. When the activity is restored, MapView must be called. onResume () */mMapView. onResume (); super. onResume () ;}@ Override protected void onDestroy () {/*** the life cycle of MapView is synchronized with the Activity. When the activity is destroyed, MapView must be called. destroy () */mMapView. destroy (); super. onDestroy () ;}@ Override protected void onSaveInstanceState (Bundle outState) {super. onSaveInstanceState (outState); mMapView. onSaveInstanceState (outState) ;}@ Override protected void onRestoreInstanceState (Bundle savedInstanceState) {super. onRestoreInstanceState (savedInstanceState); mMapView. onRestoreInstanceState (savedInstanceState );}}

4: run:

[Note] the configuration of AndroidManifest. xml is the same as that in the previous article.