安卓开发_慕课网_百度地图_实现方向传感器

学习内容来自“慕课网”

这里学习百度地图方向传感器功能

就是当转动手机的时候，地图上显示个人所在位置的图标的箭头变动

学习接自前两篇

安卓开发_慕课网_百度地图

安卓开发_慕课网_百度地图_实现定位

思路：

传感器随着定位的开始而开启，随着定位的结束而结束

传感器获得位置的移动而更新方向

代码在前两篇的基础上修改

一、讲原本坐标的图标改成箭头图标

二、引入方向传感器

首先增添MainActivity.java中的自定义图标和方向传感器代码

看红色字体的部分

package com.example.map;

import com.baidu.location.BDLocation;
import com.baidu.location.BDLocationListener;
import com.baidu.location.LocationClient;
import com.baidu.location.LocationClientOption;
import com.baidu.mapapi.SDKInitializer;
import com.baidu.mapapi.map.BaiduMap;
import com.baidu.mapapi.map.BitmapDescriptor;
import com.baidu.mapapi.map.BitmapDescriptorFactory;
import com.baidu.mapapi.map.MapStatusUpdate;
import com.baidu.mapapi.map.MapStatusUpdateFactory;
import com.baidu.mapapi.map.MapView;
import com.baidu.mapapi.map.MyLocationConfiguration;
import com.baidu.mapapi.map.MyLocationConfiguration.LocationMode;
import com.baidu.mapapi.map.MyLocationData;
import com.baidu.mapapi.model.LatLng;
import com.example.map.MyOrientationListener.OnOrientationListener;
import com.example.map.R;

import android.location.Location;
import android.os.Bundle;
import android.app.Activity;
import android.content.Context;
import android.graphics.Bitmap;
import android.view.Menu;
import android.view.MenuItem;
import android.view.Window;
import android.widget.Toast;

public class MainActivity extends Activity {
    
    private MapView mMapView = null;
    private BaiduMap mBaiduMap;
    //简化代码            用于this.context=this;
    private Context context;
    //定位相关
    private LocationClient mLocationClient;
    private MyLocationListener mLocationListener;
    //是否第一次定位的标志
    private boolean isFirstIn = true;
    //定位经纬度
    private double mLatitude;
    private double mLongtitude;
    //自定义定位图标
 46     private BitmapDescriptor mIconLocation;
 47     private LocationMode mLocationMode;//控制模式
 48     private MyOrientationListener myOrientationListener;
 49     private float mCurrentX;
    
    
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
      //在使用SDK各组件之前初始化context信息，传入ApplicationContext  
        //注意该方法要再setContentView方法之前实现  
        SDKInitializer.initialize(getApplicationContext());  
        
        requestWindowFeature(Window.FEATURE_NO_TITLE);
        setContentView(R.layout.activity_main);
        this.context = this;
        initView();
        //初始化定位
        initLocation();
        
    }
    
    private void initView() {
        // TODO Auto-generated method stub
        mMapView = (MapView) findViewById(R.id.bmapView);
        mBaiduMap = mMapView.getMap();
        //设置打开时的显示比列  这里显示500m左右
        MapStatusUpdate msu = MapStatusUpdateFactory.zoomTo(15.0f); 
        mBaiduMap.setMapStatus(msu);
        }
    private void initLocation() {
        // TODO Auto-generated method stub
        mLocationClient = new LocationClient(this);
        mLocationListener = new MyLocationListener();
        mLocationClient.registerLocationListener(mLocationListener);
        LocationClientOption option = new LocationClientOption();
        option.setCoorType("bd09ll");
        option.setIsNeedAddress(true);
        option.setOpenGps(true);
        option.setScanSpan(1000);
        
        mLocationClient.setLocOption(option);
 88         
 89         // 初始化图标
 90         mIconLocation = BitmapDescriptorFactory.fromResource(R.drawable.navi_map_gps_locked);
 91         myOrientationListener = new MyOrientationListener(context);
 92         myOrientationListener.setOnOrientationListener(new OnOrientationListener()
 93         {
 94             @Override
 95             public void onOrientationChanged(float x)
 96             {
 97                 mCurrentX = x;
 98             }
 99         });
    }
    //activity销毁时百度地图也销毁
    @Override  
    protected void onDestroy() {   
        super.onDestroy();  
        //在activity执行onDestroy时执行mMapView.onDestroy()，实现地图生命周期管理  
        mMapView.onDestroy();  
    }  
    @Override
    protected void onStart() {
        // TODO Auto-generated method stub
        super.onStart();
        // 开启定位
        mBaiduMap.setMyLocationEnabled(true);
        if (!mLocationClient.isStarted())
            mLocationClient.start();
        // 开启方向传感器
117         myOrientationListener.start();
            
    }
    @Override
    protected void onStop() {
        // TODO Auto-generated method stub
        super.onStop();
        // 停止定位
        mBaiduMap.setMyLocationEnabled(false);
        mLocationClient.stop();
        // 停止方向传感器
128         myOrientationListener.stop();
    }
    @Override  
    protected void onResume() {  
        super.onResume();  
        //在activity执行onResume时执行mMapView. onResume ()，实现地图生命周期管理  
        mMapView.onResume();  
        }  
    @Override  
    protected void onPause() {  
        super.onPause();  
        //在activity执行onPause时执行mMapView. onPause ()，实现地图生命周期管理  
        mMapView.onPause();  
        }  
    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        // TODO Auto-generated method stub
        
        getMenuInflater().inflate(R.menu.main, menu);
        return true;
    }
    //菜单按钮的响应事件
    @Override
    public boolean onOptionsItemSelected(MenuItem item) {
        // TODO Auto-generated method stub
        switch (item.getItemId()) {
        case R.id.id_map_common:
            mBaiduMap.setMapType(BaiduMap.MAP_TYPE_NORMAL);
            break;
        case R.id.id_map_site:
            mBaiduMap.setMapType(BaiduMap.MAP_TYPE_SATELLITE);
            break;
        case R.id.id_map_traffic:
            if(mBaiduMap.isTrafficEnabled())
            {
                mBaiduMap.setTrafficEnabled(false);
                item.setTitle("实时交通(off)");
            }
            else
            {
                mBaiduMap.setTrafficEnabled(true);
                item.setTitle("实时交通(on)");
            }
            break;
        case R.id.id_map_location:
            //定位最新自己的位置
            centerToMyLocation();
            break;

        default:
            break;
        }
        return super.onOptionsItemSelected(item);
    }
    //进到自己的位置
    private void centerToMyLocation() {
        LatLng latLng = new LatLng(mLatitude,mLongtitude);
        
        MapStatusUpdate msu = MapStatusUpdateFactory.newLatLng(latLng);
        mBaiduMap.animateMapStatus(msu);
    }
    private class MyLocationListener implements BDLocationListener{

        @Override
        public void onReceiveLocation(BDLocation location) {
            // TODO Auto-generated method stub
            MyLocationData data = new MyLocationData.Builder()//
            .direction(mCurrentX)//
            .accuracy(location.getRadius())//
            .latitude(location.getLatitude())//
            .longitude(location.getLongitude())//
            .build();
    mBaiduMap.setMyLocationData(data);
    // 设置自定义图标
202     MyLocationConfiguration config = new MyLocationConfiguration(mLocationMode.NORMAL, true, mIconLocation);
203     mBaiduMap.setMyLocationConfigeration(config);
    //获取最新经纬度
    mLatitude = location.getLatitude();
    mLongtitude = location.getLongitude();
    //判断是否第一次定位
    if (isFirstIn)
    {
        //设置经纬度
        LatLng latLng = new LatLng(location.getLatitude(),location.getLongitude());
        
        MapStatusUpdate msu = MapStatusUpdateFactory.newLatLng(latLng);
        mBaiduMap.animateMapStatus(msu);
        //将是否第一次定位的标志 变为不是第一次定位
        isFirstIn = false;
        //显示当前定位的位置
        Toast.makeText(context, location.getAddrStr(),
                Toast.LENGTH_SHORT).show();
    }

        }
        
    }
}

添加方向传感器部分的类

MyLocationListener.java

package com.example.map;

import android.content.Context;
import android.hardware.Sensor;
import android.hardware.SensorEvent;
import android.hardware.SensorEventListener;
import android.hardware.SensorManager;

public class MyOrientationListener implements SensorEventListener
{
    private SensorManager mSensorManager;
    private Context mContext;
    //传感器
    private Sensor mSensor;
    private float lastX;

    //构造方法
    public MyOrientationListener(Context context)
    {
        this.mContext = context;
    }

    @SuppressWarnings("deprecation")
    //开始监听
    public void start()
    {
        //拿到系统服务
        mSensorManager = (SensorManager) mContext.getSystemService(Context.SENSOR_SERVICE);
        if (mSensorManager != null)
        {
            // 获得方向传感器
            mSensor = mSensorManager.getDefaultSensor(Sensor.TYPE_ORIENTATION);
        }

        if (mSensor != null)
        {
            mSensorManager.registerListener(this, mSensor,
                    SensorManager.SENSOR_DELAY_UI);
        }
    }

    //结束监听
    public void stop()
    {
        mSensorManager.unregisterListener(this);
    }

    @Override
    public void onAccuracyChanged(Sensor arg0, int arg1)
    {
        // TODO Auto-generated method stub

    }

    @SuppressWarnings(
    { "deprecation" })
    @Override
    //方向发生变化
    public void onSensorChanged(SensorEvent event)
    {
        if (event.sensor.getType() == Sensor.TYPE_ORIENTATION)
        {
            float x = event.values[SensorManager.DATA_X];

            if (Math.abs(x - lastX) > 1.0)
            {
                if (mOnOrientationListener != null)
                {
                    mOnOrientationListener.onOrientationChanged(x);
                }
            }

            lastX = x;

        }
    }

    private OnOrientationListener mOnOrientationListener;

    public void setOnOrientationListener(
            OnOrientationListener mOnOrientationListener)
    {
        this.mOnOrientationListener = mOnOrientationListener;
    }

    public interface OnOrientationListener
    {
        void onOrientationChanged(float x);
    }

}

改动以上两部分后便可以看到效果，移动手机方向，坐标箭头方向随之变化

效果图

             

坐标箭头的素材