强制更新多次:Gps位置3-6秒

时间:2011-05-31 19:33:55

标签: android gps locationmanager locationlistener

我的应用需要使用新的当前GPS参数(每次从3到8秒后更新):纬度和经度。我正在使用两者:GPS提供商和网络提供商。 我知道用来更新GPS参数

if(gps_enabled)
     lm.requestLocationUpdates(LocationManager.GPS_PROVIDER, 0, 0, locationListenerGps);

if(network_enabled)
     lm.requestLocationUpdates(LocationManager.NETWORK_PROVIDER, 0, 0, locationListenerNetwork);

问题:事实上,每次环境后的gps更新40-50秒

如何在3-8秒后获得GPS更新?

谢谢你

4 个答案:

答案 0 :(得分:2)

try{gps_enabled=lm.isProviderEnabled(LocationManager.GPS_PROVIDER);}catch(Exception ex){}
                try{network_enabled=lm.isProviderEnabled(LocationManager.NETWORK_PROVIDER);}catch(Exception ex){}

// lm是locationManager

事实上。我不使用条件:network_enabled或网络提供商来获取位置。 --->它工作和新代码:

 lm.requestLocationUpdates(LocationManager.GPS_PROVIDER, 2000, 0, locationListenerGps);

原因是,我不使用Network_Provider。因为,当2个GPS和网络提供商,系统将使用NEtwork_provider。但是在logcat中,我看到智能手机没有使用Network_provider更新“Listenter”循环3-6s。 En revanche,GPS_PROVIDER,智能手机更新3-6s。

- 第一次打开GPS;我需要30-50秒才能拥有第一个Listener。但没关系

答案 1 :(得分:2)

我写了一个小应用程序,它将返回位置,平均速度和当前速度。当我在手机上运行它(HTC Legend)时,它每秒更新1-2次。如果你愿意,非常欢迎你使用它。你只需要创建一个包含6个textviews的main.xml文件,然后将这一行添加到你的AndroidManifest.xmll文件中:

package Hartford.gps;

import java.math.BigDecimal;

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

public class GPSMain extends Activity implements LocationListener {

LocationManager locationManager;
LocationListener locationListener;

//text views to display latitude and longitude
TextView latituteField;
TextView longitudeField;
TextView currentSpeedField;
TextView kmphSpeedField;
TextView avgSpeedField;
TextView avgKmphField;

//objects to store positional information
protected double lat;
protected double lon;

//objects to store values for current and average speed
protected double currentSpeed;
protected double kmphSpeed;
protected double avgSpeed;
protected double avgKmph;
protected double totalSpeed;
protected double totalKmph;

//counter that is incremented every time a new position is received, used to calculate average speed
int counter = 0;

/** Called when the activity is first created. */
@Override
public void onCreate(Bundle savedInstanceState) {

    super.onCreate(savedInstanceState);
    setContentView(R.layout.main);

    run();
}

@Override
public void onResume() {
    locationManager.requestLocationUpdates(LocationManager.GPS_PROVIDER, 0, 1, this);
    super.onResume();
}

@Override
public void onPause() {
    locationManager.removeUpdates(this);
    super.onPause();
}

private void run(){

    final Criteria criteria = new Criteria();

    criteria.setAccuracy(Criteria.ACCURACY_FINE);
    criteria.setSpeedRequired(true);
    criteria.setAltitudeRequired(false);
    criteria.setBearingRequired(false);
    criteria.setCostAllowed(true);
    criteria.setPowerRequirement(Criteria.POWER_LOW);
    //Acquire a reference to the system Location Manager

    locationManager = (LocationManager) this.getSystemService(Context.LOCATION_SERVICE);

    // Define a listener that responds to location updates
    locationListener = new LocationListener() {

        public void onLocationChanged(Location newLocation) {

            counter++;

            //current speed fo the gps device
            currentSpeed = round(newLocation.getSpeed(),3,BigDecimal.ROUND_HALF_UP);
            kmphSpeed = round((currentSpeed*3.6),3,BigDecimal.ROUND_HALF_UP);

            //all speeds added together
            totalSpeed = totalSpeed + currentSpeed;
            totalKmph = totalKmph + kmphSpeed;

            //calculates average speed
            avgSpeed = round(totalSpeed/counter,3,BigDecimal.ROUND_HALF_UP);
            avgKmph = round(totalKmph/counter,3,BigDecimal.ROUND_HALF_UP);

            //gets position
            lat = round(((double) (newLocation.getLatitude())),3,BigDecimal.ROUND_HALF_UP);
            lon = round(((double) (newLocation.getLongitude())),3,BigDecimal.ROUND_HALF_UP);

            latituteField = (TextView) findViewById(R.id.lat);
            longitudeField = (TextView) findViewById(R.id.lon);             
            currentSpeedField = (TextView) findViewById(R.id.speed);
            kmphSpeedField = (TextView) findViewById(R.id.kmph);
            avgSpeedField = (TextView) findViewById(R.id.avgspeed);
            avgKmphField = (TextView) findViewById(R.id.avgkmph);

            latituteField.setText("Current Latitude:        "+String.valueOf(lat));
            longitudeField.setText("Current Longitude:      "+String.valueOf(lon));
            currentSpeedField.setText("Current Speed (m/s):     "+String.valueOf(currentSpeed));
            kmphSpeedField.setText("Cuttent Speed (kmph):       "+String.valueOf(kmphSpeed));
            avgSpeedField.setText("Average Speed (m/s):     "+String.valueOf(avgSpeed));
            avgKmphField.setText("Average Speed (kmph):     "+String.valueOf(avgKmph));

        }

        //not entirely sure what these do yet
        public void onStatusChanged(String provider, int status, Bundle extras) {}
        public void onProviderEnabled(String provider) {}
        public void onProviderDisabled(String provider) {}

    };

    // Register the listener with the Location Manager to receive location updates
    locationManager.requestLocationUpdates(LocationManager.GPS_PROVIDER, 0, 1, locationListener);
}

//Method to round the doubles to a max of 3 decimal places
public static double round(double unrounded, int precision, int roundingMode)
{
    BigDecimal bd = new BigDecimal(unrounded);
    BigDecimal rounded = bd.setScale(precision, roundingMode);
    return rounded.doubleValue();
}


@Override
public void onLocationChanged(Location location) {
    // TODO Auto-generated method stub

}

@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

}

}

答案 2 :(得分:0)

requestLocationUpdates的minTime参数应为3000到8000

public void requestLocationUpdates (String provider, long minTime, float minDistance, LocationListener listener, Looper looper)

minTime the minimum通知的时间间隔,以毫秒为单位。此字段仅用作节省电量的提示,位置更新之间的实际时间可能大于或小于此值。

minDistance通知的最小距离间隔,以米为单位

答案 3 :(得分:0)

查看requestLocationUpdates(...)

public void requestLocationUpdates (String provider, long minTime, float minDistance, LocationListener listener)
  

自:API Level 1

     

注册指定提供商定期通知的当前活动。定期使用当前位置或状态更新来调用提供的LocationListener。

     

收到最近的位置可能需要一段时间。如果需要立即位置,应用程序可以使用getLastKnownLocation(String)方法。

     

如果用户禁用了提供程序,则更新将停止,并且将调用onProviderDisabled(String)方法。只要再次启用提供程序,就会调用onProviderEnabled(String)方法并再次启动位置更新。

     

可以使用minTime和minDistance参数控制通知频率。如果minTime大于0,则LocationManager可能会在位置更新之间休息minTime毫秒以节省电量。如果minDistance大于0,则仅当设备移动minDistance米时才会广播位置。要尽可能频繁地获取通知,请将两个参数都设置为0。

     

后台服务应该注意设置足够高的minTime,以便通过始终保持GPS或无线无线电设备,设备不会消耗太多电量。特别是,不推荐低于60000ms的值。

     

调用线程必须是Looper线程,例如调用Activity的主线程。

     

参数

     

提供要注册的提供者的名称

     

minTime通知的最小时间间隔,以毫秒为单位。此字段仅用作节省电量的提示,位置更新之间的实际时间可能大于或小于此值。

     

minDistance通知的最小距离间隔,以米为单位

     

侦听器{#link LocationListener}将为每个位置更新调用其onLocationChanged(Location)方法