确定车辆的使用android系统的GPS速度(Determining the speed of a

2019-07-22 16:10发布

站内文章 / 前端开发
59 0 0

我想知道如何让使用手机一个车辆的速度，而在使用GPS车辆就位。 我已阅读，加速度计不是很准确。 另一件事是， 而在车辆中就座将GPS访问。 会不会有它的，而你是在建筑物同样的效果？

下面是一些代码，我已经试过，但我已经使用了网络提供商instead.I会欣赏的帮助。 谢谢... 

package com.example.speedtest;

import android.app.Activity;
import android.content.Context;
import android.location.Location;
import android.location.LocationListener;
import android.location.LocationManager;
import android.os.Bundle;
import android.widget.Toast;

public class MainActivity extends Activity {
    LocationManager locManager;
    LocationListener li;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        locManager=(LocationManager)getSystemService(Context.LOCATION_SERVICE);
        li=new speed();
        locManager.requestLocationUpdates(LocationManager.NETWORK_PROVIDER, 0, 0, li);
    }
    class speed implements LocationListener{
        @Override
        public void onLocationChanged(Location loc) {
            Float thespeed=loc.getSpeed();
            Toast.makeText(MainActivity.this,String.valueOf(thespeed), Toast.LENGTH_LONG).show();
        }
        @Override
        public void onProviderDisabled(String arg0) {}
        @Override
        public void onProviderEnabled(String arg0) {}
        @Override
        public void onStatusChanged(String arg0, int arg1, Bundle arg2) {}

    }
}

Answer 1:

GPS在车辆正常工作。 该NETWORK_PROVIDER设置可能不足够精确，以得到一个可靠的速度，从位置NETWORK_PROVIDER甚至可能不包含速度。 您可以检查与location.hasSpeed() location.getSpeed()将始终返回0）。

如果您发现location.getSpeed()不够准确，或者是不稳定（即波动剧烈），那么你可以通过采取一些GPS位置和除以经过的时间之间的平均距离自己计算速度。



Answer 2:

从GPS位置变化的Android移动设备查看这个链接的更多信息onCalculate速度

主要有两种方法来计算手机的速度。

  1. 从加速度计算速度
  2. 从GPS技术计算速度

与加速度计从GPS技术，如果你要计算的速度，你必须启用数据连接和GPS连接。

在这里，我们要利用GPS连接来计算速度。 在这种方法中，我们使用频率的GPS定位点是如何在单个时间段的变化。 那么，如果我们有地缘位置点之间的实际距离，我们可以得到的速度。 因为我们的距离和时间。 速度=距离/时间而获得两个位置点之间的距离也不是很容易。 因为世界的形状为一个目标2个地理点之间的距离是从地方和角度角不同。 因此，我们必须使用“半正矢算法”

首先，我们必须给出清单文件获取地点数据许可

使GUI 

   <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    android:orientation="vertical" >

    <TextView
        android:id="@+id/txtCurrentSpeed"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="000.0 miles/hour"
        android:textAppearance="?android:attr/textAppearanceLarge" />

    <CheckBox android:id="@+id/chkMetricUnits"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="Use metric units?"/>

然后再做一个接口来获取速度 

package com.isuru.speedometer;
import android.location.GpsStatus;
import android.location.Location;
import android.location.LocationListener;
import android.os.Bundle;

public interface IBaseGpsListener extends LocationListener, GpsStatus.Listener {

      public void onLocationChanged(Location location);

      public void onProviderDisabled(String provider);

      public void onProviderEnabled(String provider);

      public void onStatusChanged(String provider, int status, Bundle extras);

      public void onGpsStatusChanged(int event);

}

实现逻辑使用GPS定位来获得速度 

import android.location.Location;

public class CLocation extends Location {

      private boolean bUseMetricUnits = false;

      public CLocation(Location location)
      {
            this(location, true);
      }

      public CLocation(Location location, boolean bUseMetricUnits) {
            // TODO Auto-generated constructor stub
            super(location);
            this.bUseMetricUnits = bUseMetricUnits;
      }


      public boolean getUseMetricUnits()
      {
            return this.bUseMetricUnits;
      }

      public void setUseMetricunits(boolean bUseMetricUntis)
      {
            this.bUseMetricUnits = bUseMetricUntis;
      }

      @Override
      public float distanceTo(Location dest) {
            // TODO Auto-generated method stub
            float nDistance = super.distanceTo(dest);
            if(!this.getUseMetricUnits())
            {
                  //Convert meters to feet
                  nDistance = nDistance * 3.28083989501312f;
            }
            return nDistance;
      }

      @Override
      public float getAccuracy() {
            // TODO Auto-generated method stub
            float nAccuracy = super.getAccuracy();
            if(!this.getUseMetricUnits())
            {
                  //Convert meters to feet
                  nAccuracy = nAccuracy * 3.28083989501312f;
            }
            return nAccuracy;
      }

      @Override
      public double getAltitude() {
            // TODO Auto-generated method stub
            double nAltitude = super.getAltitude();
            if(!this.getUseMetricUnits())
            {
                  //Convert meters to feet
                  nAltitude = nAltitude * 3.28083989501312d;
            }
            return nAltitude;
      }

      @Override
      public float getSpeed() {
            // TODO Auto-generated method stub
            float nSpeed = super.getSpeed() * 3.6f;
            if(!this.getUseMetricUnits())
            {
                  //Convert meters/second to miles/hour
                  nSpeed = nSpeed * 2.2369362920544f/3.6f;
            }
            return nSpeed;
      }



}

结合逻辑GUI 

import java.util.Formatter;
import java.util.Locale;

import android.location.Location;
import android.location.LocationManager;
import android.os.Bundle;
import android.app.Activity;
import android.content.Context;
import android.view.Menu;
import android.widget.CheckBox;
import android.widget.CompoundButton;
import android.widget.CompoundButton.OnCheckedChangeListener;
import android.widget.TextView;

public class MainActivity extends Activity implements IBaseGpsListener {

      @Override
      protected void onCreate(Bundle savedInstanceState) {
            super.onCreate(savedInstanceState);
            setContentView(R.layout.activity_main);
            LocationManager locationManager = (LocationManager) this.getSystemService(Context.LOCATION_SERVICE);
            locationManager.requestLocationUpdates(LocationManager.GPS_PROVIDER, 0, 0, this);
            this.updateSpeed(null);

            CheckBox chkUseMetricUntis = (CheckBox) this.findViewById(R.id.chkMetricUnits);
            chkUseMetricUntis.setOnCheckedChangeListener(new OnCheckedChangeListener() {

                  @Override
                  public void onCheckedChanged(CompoundButton buttonView, boolean isChecked) {
                        // TODO Auto-generated method stub
                        MainActivity.this.updateSpeed(null);
                  }
            });
      }

      public void finish()
      {
            super.finish();
            System.exit(0);
      }

      private void updateSpeed(CLocation location) {
            // TODO Auto-generated method stub
            float nCurrentSpeed = 0;

            if(location != null)
            {
                  location.setUseMetricunits(this.useMetricUnits());
                  nCurrentSpeed = location.getSpeed();
            }

            Formatter fmt = new Formatter(new StringBuilder());
            fmt.format(Locale.US, "%5.1f", nCurrentSpeed);
            String strCurrentSpeed = fmt.toString();
            strCurrentSpeed = strCurrentSpeed.replace(' ', '0');

            String strUnits = "miles/hour";
            if(this.useMetricUnits())
            {
                  strUnits = "meters/second";
            }

            TextView txtCurrentSpeed = (TextView) this.findViewById(R.id.txtCurrentSpeed);
            txtCurrentSpeed.setText(strCurrentSpeed + " " + strUnits);
      }

      private boolean useMetricUnits() {
            // TODO Auto-generated method stub
            CheckBox chkUseMetricUnits = (CheckBox) this.findViewById(R.id.chkMetricUnits);
            return chkUseMetricUnits.isChecked();
      }

      @Override
      public void onLocationChanged(Location location) {
            // TODO Auto-generated method stub
            if(location != null)
            {
                  CLocation myLocation = new CLocation(location, this.useMetricUnits());
                  this.updateSpeed(myLocation);
            }
      }

      @Override
      public void onProviderDisabled(String provider) {
            // TODO Auto-generated method stub

      }

      @Override
      public void onProviderEnabled(String provider) {
            // TODO Auto-generated method stub

      }

      @Override
      public void onStatusChanged(String provider, int status, Bundle extras) {
            // TODO Auto-generated method stub

      }

      @Override
      public void onGpsStatusChanged(int event) {
            // TODO Auto-generated method stub

      }



}

如果你想转换米/秒至KMPH-1则需要含多处百米从3.6 /秒的答案

速度从KMPH-1 = 3.6 *（速度从MS-1）



Answer 3:

public class MainActivity extends Activity implements LocationListener {

添加工具LocationListener的旁边活动

LocationManager lm =(LocationManager) this.getSystemService(Context.LOCATION_SERVICE);
        lm.requestLocationUpdates(LocationManager.GPS_PROVIDER, 0, 0, this);
        this.onLocationChanged(null);

LocationManager.GPS_PROVIDER，0，0，第一个零代表minTime以及您更新你的价值观，第二个为minDistance才会。 零意味着基本的即时更新，可以是坏的电池寿命，所以你可能需要调整它。 

     @Override
    public void onLocationChanged(Location location) {

    if (location==null){
         // if you can't get speed because reasons :)
        yourTextView.setText("00 km/h");
    }
    else{
        //int speed=(int) ((location.getSpeed()) is the standard which returns meters per second. In this example i converted it to kilometers per hour

        int speed=(int) ((location.getSpeed()*3600)/1000);

        yourTextView.setText(speed+" km/h");
    }
}


@Override
public void onStatusChanged(String provider, int status, Bundle extras) {
    // TODO Auto-generated method stub

}


@Override
public void onProviderEnabled(String provider) {
    // TODO Auto-generated method stub

}


@Override
public void onProviderDisabled(String provider) {


}

不要忘了权限

 <uses-permission android:name="android.permission.ACCESS_FINE_LOCATION"/>


Answer 4:

我们可以用location.getSpeed（）; 

  try {
                // Get the location manager
                double lat;
                double lon;
                double speed = 0;
                LocationManager locationManager = (LocationManager)
                        getActivity().getSystemService(LOCATION_SERVICE);
                Criteria criteria = new Criteria();
                String bestProvider = locationManager.getBestProvider(criteria, false);
                if (ActivityCompat.checkSelfPermission(getActivity(), Manifest.permission.ACCESS_FINE_LOCATION) != PackageManager.PERMISSION_GRANTED && ActivityCompat.checkSelfPermission(getActivity(), Manifest.permission.ACCESS_COARSE_LOCATION) != PackageManager.PERMISSION_GRANTED) {
                    // TODO: Consider calling
                    //    ActivityCompat#requestPermissions
                    // here to request the missing permissions, and then overriding
                    //   public void onRequestPermissionsResult(int requestCode, String[] permissions,
                    //                                          int[] grantResults)
                    // to handle the case where the user grants the permission. See the documentation
                    // for ActivityCompat#requestPermissions for more details.
                    return;
                }
                Location location = locationManager.getLastKnownLocation(bestProvider);
                try {
                    lat = location.getLatitude();
                    lon = location.getLongitude();
                    speed =location.getSpeed();
                } catch (NullPointerException e) {
                    lat = -1.0;
                    lon = -1.0;
                }

                mTxt_lat.setText("" + lat);
                mTxt_speed.setText("" + speed);

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


文章来源: Determining the speed of a vehicle using GPS in android
标签： android gps location android-location
举报

收藏的人(0)

Ta的文章 更多文章
登录 后发表评论
0条评论
还没有人评论过~