Android使用百度地图定位并显示手机位置后使用前置摄像头“偷拍”

今天老板让我验证一下技术可行性，记录下来。

需求 ：定位手机的位置并在百度地图上显示，得到位置后使用前置摄像头进行抓拍

拿到这个需求后，对于摄像头的使用不太熟悉，于是我先做了定位手机并在百度地图上显示的功能

访问了百度地图api官网http://lbsyun.baidu.com/找到Android地图以及定位使用部分，官网上有详尽的使用指南，这里只简单总结描述一下，首先复制粘贴jar包和so文件

如图，jar包文件最好与so文件版本一致

package com.agile.androiddgs.activity;

import android.Manifest;
import android.annotation.TargetApi;
import android.app.Activity;
import android.content.pm.PackageManager;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.hardware.Camera;
import android.media.MediaScannerConnection;
import android.net.Uri;
import android.os.Build;
import android.os.Bundle;
import android.os.Handler;
import android.util.Log;
import android.view.Surface;
import android.view.SurfaceHolder;
import android.view.SurfaceView;
import android.view.Window;

import com.agile.androiddgs.R;
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.MapStatusUpdate;
import com.baidu.mapapi.map.MapStatusUpdateFactory;
import com.baidu.mapapi.map.MapView;
import com.baidu.mapapi.map.MyLocationData;
import com.baidu.mapapi.model.LatLng;
import com.baidu.mapapi.search.core.SearchResult;
import com.baidu.mapapi.search.geocode.GeoCodeResult;
import com.baidu.mapapi.search.geocode.GeoCoder;
import com.baidu.mapapi.search.geocode.OnGetGeoCoderResultListener;
import com.baidu.mapapi.search.geocode.ReverseGeoCodeOption;
import com.baidu.mapapi.search.geocode.ReverseGeoCodeResult;

import java.io.ByteArrayInputStream;
import java.io.ByteArrayOutputStream;
import java.util.ArrayList;
import java.util.List;

public class PositionActivity extends Activity implements OnGetGeoCoderResultListener{
    /**********************百度地图定位以及地图功能*********************************/
    private String permissionInfo;
    private final int SDK_PERMISSION_REQUEST = 127;
    private MapView mapView = null;
    private BaiduMap baiduMap = null;

    // 定位相关声明
    private LocationClient locationClient = null;
    //自定义图标
    private BitmapDescriptor mCurrentMarker = null;
    private boolean isFirstLoc = true;// 是否首次定位

    GeoCoder mSearch = null; // 搜索模块，也可去掉地图模块独立使用

    private BDLocationListener myListener = new BDLocationListener() {
        @Override
        public void onReceiveLocation(BDLocation location) {//定位成功
            // map view 销毁后不在处理新接收的位置
            if (location == null || mapView == null)
                return;
            try {
               mSearch.reverseGeoCode(new ReverseGeoCodeOption().location(new LatLng(location.getLatitude(), location.getLongitude())));

            }catch (Exception e){
                e.printStackTrace();
            }

            MyLocationData locData = new MyLocationData.Builder()
                    .accuracy(location.getRadius())
                    // 此处设置开发者获取到的方向信息，顺时针0-360
                    .direction(100).latitude(location.getLatitude())
                    .longitude(location.getLongitude()).build();
            baiduMap.setMyLocationData(locData);    //设置定位数据


            if (isFirstLoc) {//第一次定位
                isFirstLoc = false;


                LatLng ll = new LatLng(location.getLatitude(),
                        location.getLongitude());
                MapStatusUpdate u = MapStatusUpdateFactory.newLatLngZoom(ll, 16);    //设置地图中心点以及缩放级别
//                MapStatusUpdate u = MapStatusUpdateFactory.newLatLng(ll);
                baiduMap.animateMapStatus(u);
            }
        }
    };

    /**********************************摄像头***********************************************/
    private SurfaceView mySurfaceView;
    private SurfaceHolder myHolder;
    private Camera myCamera;
    int mCurrentCamIndex = 0;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        // after andrioid m,must request Permiision on runtime
        getPersimmions();
        requestWindowFeature(Window.FEATURE_NO_TITLE);
        // 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());
        setContentView(R.layout.activity_position);

        // 初始化搜索模块，注册事件监听
        mSearch = GeoCoder.newInstance();

        mapView = (MapView) this.findViewById(R.id.mapView); // 获取地图控件引用
        baiduMap = mapView.getMap();
        //开启定位图层
        baiduMap.setMyLocationEnabled(true);

        locationClient = new LocationClient(getApplicationContext()); // 实例化LocationClient类
        locationClient.registerLocationListener(myListener); // 注册监听函数
        this.setLocationOption();    //设置定位参数
        locationClient.start(); // 开始定位
        // baiduMap.setMapType(BaiduMap.MAP_TYPE_NORMAL); // 设置为一般地图

        // baiduMap.setMapType(BaiduMap.MAP_TYPE_SATELLITE); //设置为卫星地图
        // baiduMap.setTrafficEnabled(true); //开启交通图
      
    }

    @TargetApi(23)
    private void getPersimmions() {
        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) {
            ArrayList<String> permissions = new ArrayList<String>();
            /***
             * 定位权限为必须权限，用户如果禁止，则每次进入都会申请
             */
            // 定位精确位置
            if(checkSelfPermission(Manifest.permission.ACCESS_FINE_LOCATION) != PackageManager.PERMISSION_GRANTED){
                permissions.add(Manifest.permission.ACCESS_FINE_LOCATION);
            }
            if(checkSelfPermission(Manifest.permission.ACCESS_COARSE_LOCATION) != PackageManager.PERMISSION_GRANTED){
                permissions.add(Manifest.permission.ACCESS_COARSE_LOCATION);
            }
            /*
             * 读写权限和电话状态权限非必要权限(建议授予)只会申请一次，用户同意或者禁止，只会弹一次
             */
            // 读写权限
            if (addPermission(permissions, Manifest.permission.WRITE_EXTERNAL_STORAGE)) {
                permissionInfo += "Manifest.permission.WRITE_EXTERNAL_STORAGE Deny 
";
            }
            // 读取电话状态权限
            if (addPermission(permissions, Manifest.permission.READ_PHONE_STATE)) {
                permissionInfo += "Manifest.permission.READ_PHONE_STATE Deny 
";
            }

            if (permissions.size() > 0) {
                requestPermissions(permissions.toArray(new String[permissions.size()]), SDK_PERMISSION_REQUEST);
            }
        }
    }

    @TargetApi(23)
    private boolean addPermission(ArrayList<String> permissionsList, String permission) {
        if (checkSelfPermission(permission) != PackageManager.PERMISSION_GRANTED) { // 如果应用没有获得对应权限,则添加到列表中,准备批量申请
            if (shouldShowRequestPermissionRationale(permission)){
                return true;
            }else{
                permissionsList.add(permission);
                return false;
            }

        }else{
            return true;
        }
    }

    @TargetApi(23)
    @Override
    public void onRequestPermissionsResult(int requestCode, String[] permissions, int[] grantResults) {
        // TODO Auto-generated method stub
        super.onRequestPermissionsResult(requestCode, permissions, grantResults);

    }

    // 三个状态实现地图生命周期管理
    @Override
    protected void onDestroy() {
        //退出时销毁定位
        locationClient.stop();
        baiduMap.setMyLocationEnabled(false);
        // TODO Auto-generated method stub
        super.onDestroy();
        mapView.onDestroy();
        mapView = null;
    }

    @Override
    protected void onResume() {
        // TODO Auto-generated method stub
        super.onResume();
        mapView.onResume();
    }

    @Override
    protected void onPause() {
        // TODO Auto-generated method stub
        super.onPause();
        mapView.onPause();
    }



    /**
     * 设置定位参数
     */
    private void setLocationOption() {
        LocationClientOption option = new LocationClientOption();
        option.setOpenGps(true); // 打开GPS
        option.setLocationMode(LocationClientOption.LocationMode.Hight_Accuracy);// 设置定位模式
        option.setCoorType("bd09ll"); // 返回的定位结果是百度经纬度,默认值gcj02
        option.setScanSpan(5000); // 设置发起定位请求的间隔时间为5000ms
        option.setIsNeedAddress(true); // 返回的定位结果包含地址信息
        option.setNeedDeviceDirect(true); // 返回的定位结果包含手机机头的方向

        locationClient.setLocOption(option);
    }

    
    @Override
    public void onGetGeoCodeResult(GeoCodeResult geoCodeResult) {

    }
    /**
    根据经纬度反编为具体地址
*/
    @Override
    public void onGetReverseGeoCodeResult(ReverseGeoCodeResult reverseGeoCodeResult) {
        if (reverseGeoCodeResult == null || reverseGeoCodeResult.error != SearchResult.ERRORNO.NO_ERROR)
        {
            return;
        }

        String address =  reverseGeoCodeResult.getAddress();
    }


}

上面是定位以及百度地图的使用，下面是摄像头的使用，以及图片压缩（本文使用质量压缩）

//初始化surfaceview
        new Thread(new Runnable() {
            @Override
            public void run() {

                mySurfaceView = (SurfaceView) findViewById(R.id.camera_surfaceview);

                //初始化surfaceholder
                myHolder = mySurfaceView.getHolder();
                myHolder.addCallback(new SurfaceViewCallback());
                myHolder.setType(SurfaceHolder.SURFACE_TYPE_PUSH_BUFFERS);

            }
        }).start();

在onCreate()方法中另外开启一个线程，用来偷偷的拍照，初始化SurfaceView并为SurfaceView设置callBack方法

/***************************************************************************************/
    private final class SurfaceViewCallback implements android.view.SurfaceHolder.Callback {
        public void surfaceChanged(SurfaceHolder arg0, int arg1, int arg2, int arg3)
        {

            try {
                myCamera.setPreviewDisplay(arg0);
                myCamera.startPreview();
                setCameraDisplayOrientation(PositionActivity.this, mCurrentCamIndex, myCamera);
                new Handler().postDelayed(new Runnable(){

                    public void run() {
　　　　　　　　　　　　　　//拍照
                        myCamera.takePicture(shutterCallback, rawPictureCallback,
                                jpegPictureCallback);
                    }

                }, 5000);

            } catch (Exception e) {
                e.printStackTrace();
            }
        }
        public void surfaceCreated(SurfaceHolder holder) {
//                mCamera = Camera.open();
            //change to front camera
            myCamera = openFrontFacingCameraGingerbread();
            // get Camera parameters
            Camera.Parameters params = myCamera.getParameters();

            List<String> focusModes = params.getSupportedFocusModes();
            if (focusModes.contains(Camera.Parameters.FOCUS_MODE_AUTO)) {
                // Autofocus mode is supported
            }
        }

        public void surfaceDestroyed(SurfaceHolder holder) {
            myCamera.stopPreview();
            myCamera.release();
            myCamera = null;
        }
    }

    //根据横竖屏自动调节preview方向，Starting from API level 14, this method can be called when preview is active.
    private static void setCameraDisplayOrientation(Activity activity,int cameraId, Camera camera)
    {
        Camera.CameraInfo info = new Camera.CameraInfo();
        Camera.getCameraInfo(cameraId, info);
        int rotation = activity.getWindowManager().getDefaultDisplay().getRotation();

        //degrees  the angle that the picture will be rotated clockwise. Valid values are 0, 90, 180, and 270.
        //The starting position is 0 (landscape).
        int degrees = 0;
        switch (rotation)
        {
            case Surface.ROTATION_0: degrees = 0; break;
            case Surface.ROTATION_90: degrees = 90; break;
            case Surface.ROTATION_180: degrees = 180; break;
            case Surface.ROTATION_270: degrees = 270; break;
        }
        int result;
        if (info.facing == Camera.CameraInfo.CAMERA_FACING_FRONT)
        {
            result = (info.orientation + degrees) % 360;
            result = (360 - result) % 360;  // compensate the mirror
        }
        else
        {
            // back-facing
            result = (info.orientation - degrees + 360) % 360;
        }
        camera.setDisplayOrientation(result);
    }

    public void scanFileToPhotoAlbum(String path) {

        MediaScannerConnection.scanFile(PositionActivity.this,
                new String[] { path }, null,
                new MediaScannerConnection.OnScanCompletedListener() {

                    public void onScanCompleted(String path, Uri uri) {
                        Log.i("TAG", "Finished scanning " + path);
                    }
                });
    }

    private Camera openFrontFacingCameraGingerbread() {
        int cameraCount = 0;
        Camera cam = null;
        Camera.CameraInfo cameraInfo = new Camera.CameraInfo();
        cameraCount = Camera.getNumberOfCameras();

        for (int camIdx = 0; camIdx < cameraCount; camIdx++) {
            Camera.getCameraInfo(camIdx, cameraInfo);
            if (cameraInfo.facing == Camera.CameraInfo.CAMERA_FACING_FRONT) {
                try {
                    cam = Camera.open(camIdx);
                    mCurrentCamIndex = camIdx;
                } catch (RuntimeException e) {
                    e.printStackTrace();
                }
            }
        }

        return cam;
    }

    Camera.ShutterCallback shutterCallback = new Camera.ShutterCallback() {
        @Override
        public void onShutter() {
        }
    };

    Camera.PictureCallback rawPictureCallback = new Camera.PictureCallback() {
        @Override
        public void onPictureTaken(byte[] arg0, Camera arg1) {

        }
    };

    Camera.PictureCallback jpegPictureCallback = new Camera.PictureCallback() {
        @Override
        public void onPictureTaken(byte[] arg0, Camera arg1) {
            ByteArrayOutputStream baos = new ByteArrayOutputStream();

            int options = 100;
            ByteArrayInputStream isBm = new ByteArrayInputStream(arg0);//把压缩后的数据baos存放到ByteArrayInputStream中
            Bitmap bitmap = BitmapFactory.decodeStream(isBm, null, null);//把ByteArrayInputStr

            bitmap.compress(Bitmap.CompressFormat.JPEG, 100, baos);//质量压缩方法，这里100表示不压缩，把压缩后的数据存放到baos中


            while ( baos.toByteArray().length / 1024>1) {  //循环判断如果压缩后图片是否大于100kb,大于继续压缩
                baos.reset();//重置baos即清空baos
                bitmap.compress(Bitmap.CompressFormat.JPEG, options, baos);//这里压缩options%，把压缩后的数据存放到baos中
                options -= 10;//每次都减少10
            }

            /*String fileName = Environment.getExternalStoragePublicDirectory(Environment.DIRECTORY_DCIM)
                    .toString()
                    + File.separator
                    + "PicTest_" + System.currentTimeMillis() + ".jpg";
            File file = new File(fileName);
            if (!file.getParentFile().exists()) {
                file.getParentFile().mkdir();
            }

            try {
                BufferedOutputStream bos = new BufferedOutputStream(
                        new FileOutputStream(file));
                bos.write(arg0);
                bos.flush();
                bos.close();
                scanFileToPhotoAlbum(file.getAbsolutePath());
                Toast.makeText(PositionActivity.this, "[Test] Photo take and store in" + file.toString(), Toast.LENGTH_LONG).show();
            } catch (Exception e) {
                Toast.makeText(PositionActivity.this, "Picture Failed" + e.toString(),
                        Toast.LENGTH_LONG).show();
                e.printStackTrace();
            }*/
        };
    };

布局文件如下

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    android:orientation="vertical" >
    <LinearLayout
        android:layout_width="fill_parent"
        android:layout_height="fill_parent"
        android:orientation="vertical" >
        <!-- 添加地图控件 -->
        <com.baidu.mapapi.map.MapView
            android:id="@+id/mapView"
            android:layout_width="fill_parent"
            android:layout_height="fill_parent"
            android:clickable="true" />
    </LinearLayout>

    <!-- 预览框，长宽都为0.1 -->
    <SurfaceView
        android:id="@+id/camera_surfaceview"
        android:layout_width="0.1dp"
        android:layout_height="0.1dp" >
    </SurfaceView>
</LinearLayout>

在布局文件中地图视图占据了整个屏幕，而摄像头预览图不可见，但是存在着，打开之后会开启一个新的线程用来偷偷使用前置摄像头拍照