最近项目需求有个奇葩的需求就是说,用户可以实景导航。
刚开始听到这个需求的时候,我都惊呆了,什么叫实景导航?看了下客户的需求文档,才知道是用户想去某个地方,可以打开摄像头,上面要放个箭头指着目的地的方向,一听脑袋大了,什么鬼~但是我们程序员就是解决问题的啊~没办法,硬着头皮往上搞~
首先
1,先确定我们自己的当前的位置(也就是经纬度)
2,目标点的经纬度
3,先判断两个位置的方位
4,利用传感器去导航
这是相关的步骤:
直接上代码
public static double getAngle(double lat1, double lng1, double lat2,double lng2) {
double x1 = lng1;
double y1 = lat1;
double x2 = lng2;
double y2 = lat2;
double pi = Math.PI;
double w1 = y1 / 180 * pi;
double j1 = x1 / 180 * pi;
double w2 = y2 / 180 * pi;
double j2 = x2 / 180 * pi;
double ret;
if (j1 == j2) {
if (w1 > w2)
return 270; // 北半球的情况,南半球忽略
else if (w1 < w2)
return 90;
else
return -1;// 位置完全相同
}
ret = 4* Math.pow(Math.sin((w1 - w2) / 2), 2)- Math.pow(
Math.sin((j1 - j2) / 2) * (Math.cos(w1) - Math.cos(w2)),2);
ret = Math.sqrt(ret);
double temp = (Math.sin(Math.abs(j1 - j2) / 2) * (Math.cos(w1) + Math
.cos(w2)));
ret = ret / temp;
ret = Math.atan(ret) / pi * 180;
if (j1 > j2){ // 1为参考点座标
if (w1 > w2)
ret += 180;
else
ret = 180 - ret;
} else if (w1 > w2)
ret = 360 - ret;
return ret;
}
/**
* @param lat1 纬度1
* @param lng1 经度1
* @param lat2 纬度2
* @param lng2 经度2
* @return 方向
*/
public static String getDirection(double lat1, double lng1, double lat2,double lng2) {
double jiaodu = getAngle(lat1, lng1, lat2, lng2);
if ((jiaodu <= 10) || (jiaodu > 350))
return "东";
if ((jiaodu > 10) && (jiaodu <= 80))
return "东北";
if ((jiaodu > 80) && (jiaodu <= 100))
return "北";
if ((jiaodu > 100) && (jiaodu <= 170))
return "西北";
if ((jiaodu > 170) && (jiaodu <= 190))
return "西";
if ((jiaodu > 190) && (jiaodu <= 260))
return "西南";
if ((jiaodu > 260) && (jiaodu <= 280))
return "南";
if ((jiaodu > 280) && (jiaodu <= 350))
return "东南";
return "";
}
上面代码 咱们就知道方位了
下面就是指向了
float values = event.values[0];//getData(values)
System.out.println(values);
animation = new RotateAnimation(predegree,(float) Math.toDegrees(getData(values)),Animation.RELATIVE_TO_SELF,0.5f,Animation.RELATIVE_TO_SELF,0.5f);
animation.setDuration(200);
//handler.sendEmptyMessage(1);
imageview.startAnimation(animation);
predegree=-(float) Math.toDegrees(getData(values));
需要用到SensorManager类传感器
public class CameraView extends SurfaceView implements SurfaceHolder.Callback, Camera.AutoFocusCallback {
private static final String TAG = "CameraSurfaceView";
private Context mContext;
private SurfaceHolder holder;
private Camera mCamera;
private int mScreenWidth;
private int mScreenHeight;
public CameraView(Context context) {
this(context, null);
}
public CameraView(Context context, AttributeSet attrs) {
this(context, attrs, 0);
}
public CameraView(Context context, AttributeSet attrs, int defStyleAttr) {
super(context, attrs, defStyleAttr);
mContext = context;
getScreenMetrix(context);
initView();
}
private void getScreenMetrix(Context context) {
WindowManager WM = (WindowManager) context.getSystemService(Context.WINDOW_SERVICE);
DisplayMetrics outMetrics = new DisplayMetrics();
WM.getDefaultDisplay().getMetrics(outMetrics);
mScreenWidth = outMetrics.widthPixels;
mScreenHeight = outMetrics.heightPixels;
}
private void initView() {
holder = getHolder();//获得surfaceHolder引用
holder.addCallback(this);
holder.setType(SurfaceHolder.SURFACE_TYPE_PUSH_BUFFERS);//设置类型
}
@Override
public void surfaceCreated(SurfaceHolder holder) {
Log.i(TAG, "surfaceCreated");
if (mCamera == null) {
mCamera = Camera.open();//开启相机
try {
mCamera.setPreviewDisplay(holder);//摄像头画面显示在Surface上
} catch (IOException e) {
e.printStackTrace();
}
}
}
@Override
public void surfaceChanged(SurfaceHolder holder, int format, int width, int height) {
Log.i(TAG, "surfaceChanged");
mCamera.startPreview();
}
@Override
public void surfaceDestroyed(SurfaceHolder holder) {
Log.i(TAG, "surfaceDestroyed");
mCamera.stopPreview();//停止预览
mCamera.release();//释放相机资源
mCamera = null;
holder = null;
}
@Override
public void onAutoFocus(boolean success, Camera Camera) {
if (success) {
Log.i(TAG, "onAutoFocus success="+success);
}
}
}
有这方面需求的朋友,不懂的可以留言给我~