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GPS无法自动启动

时间：2010-07-19

来源：互联网

网路上找到一个范例

是可以在mapview上划路线的程式

但是放在手机时

却无法自动开启GPS搜寻

导致找不到所在位置

是少写什么了吗??

(手机的GPS已设定启动)

package com.android.dara;
 
import java.text.DecimalFormat;
import java.text.NumberFormat;
import java.util.List;
import android.app.AlertDialog;
import android.content.Context;
import android.content.DialogInterface;
import android.content.Intent;
import android.os.Bundle; import android.view.View; import android.widget.Button; import android.widget.TextView;
import android.widget.Toast;
import android.location.Criteria;
import android.location.Location;
import android.location.LocationListener;
import android.location.LocationManager;
import com.google.android.maps.GeoPoint;
import com.google.android.maps.MapActivity;
import com.google.android.maps.MapController;
import com.google.android.maps.MapView;
import com.google.android.maps.Overlay;
 
public class mymap extends MapActivity
{ private TextView mTextView; private Button mButton01; private Button mButton02; private Button mButton03; private Button mButton04; private Button mButton05; private MapView mMapView; private MapController mMapController; private LocationManager mLocationManager; private Location mLocation; private String mLocationPrivider=""; private int zoomLevel=0; private GeoPoint gp1; private GeoPoint gp2; private boolean _run=false; private double distance=0;
  @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.map); /* 建立MapView物件 */ mMapView = (MapView)findViewById(R.id.myMapView1); mMapController = mMapView.getController(); /* 物件初始化 */ mTextView = (TextView)findViewById(R.id.myText1); mButton01 = (Button)findViewById(R.id.myButton1); mButton02 = (Button)findViewById(R.id.myButton2); mButton03 = (Button)findViewById(R.id.myButton3); mButton04 = (Button)findViewById(R.id.myButton4); mButton05 = (Button)findViewById(R.id.myButtonreturn); /* 设定预设的放大层级 */ zoomLevel = 17; mMapController.setZoom(zoomLevel);   /* Provider初始化 */ mLocationManager = (LocationManager) getSystemService(Context.LOCATION_SERVICE); /* 取得Provider与Location */ getLocationPrivider(); if(mLocation!=null) { /* 取得目前的经纬度 */ gp1=getGeoByLocation(mLocation); gp2=gp1; /* 将MapView的中点移至目前位置 */ refreshMapView(); /* 设定事件的Listener */ mLocationManager.requestLocationUpdates(mLocationPrivider, 2000, 10, mLocationListener); } else { new AlertDialog.Builder(mymap.this).setTitle("系统讯息") .setMessage(getResources().getString(R.string.str_message)) .setNegativeButton("确定",new DialogInterface.OnClickListener() { public void onClick(DialogInterface dialog, int which) { mymap.this.finish(); } }) .show(); } /* 开始记录的Button */ mButton01.setOnClickListener(new Button.OnClickListener() { @Override public void onClick(View v) { gp1=gp2; /* 清除Overlay */ resetOverlay(); /* 画起点 */ setStartPoint(); /* 更新MapView */ refreshMapView(); /* 重设移动距离为0，并更新TextView */ distance=0; mTextView.setText("移动距离：0M"); /* 启动画路线的机制 */ _run=true; } }); /* 结束记录的Button */ mButton02.setOnClickListener(new Button.OnClickListener() { @Override public void onClick(View v) { /* 画终点 */ setEndPoint(); /* 更新MapView */ refreshMapView(); /* 终止画路线的机制 */ _run=false; } }); /* 缩小地图的Button */ mButton04.setOnClickListener(new Button.OnClickListener() { @Override public void onClick(View v) { zoomLevel--; if(zoomLevel<1) { zoomLevel = 1; } mMapController.setZoom(zoomLevel); } }); /* 放大地图的Button */ mButton03.setOnClickListener(new Button.OnClickListener() { @Override public void onClick(View v) { zoomLevel++; if(zoomLevel>mMapView.getMaxZoomLevel()) { zoomLevel = mMapView.getMaxZoomLevel(); } mMapController.setZoom(zoomLevel); } }); mButton05.setOnClickListener(new Button.OnClickListener() { @Override public void onClick(View v) {     Intent i = new Intent(mymap.this, sample1.class); startActivity(i); } }); } /* MapView的Listener */ public final LocationListener mLocationListener = new LocationListener() { @Override public void onLocationChanged(Location location) { /* 如果记录进行中，就画路线并更新移动距离 */ if(_run) { /* 记下移动后的位置 */ gp2=getGeoByLocation(location); /* 画路线 */ setRoute(); /* 更新MapView */ refreshMapView(); /* 取得移动距离 */ distance+=GetDistance(gp1,gp2); mTextView.setText("移动距离："+format(distance)+"M");   gp1=gp2; } } @Override public void onProviderDisabled(String provider) {   Toast.makeText(
        getBaseContext(),
        "ProviderDisabled.",
        Toast.LENGTH_SHORT).show();     } @Override public void onProviderEnabled(String provider) {   Toast.makeText(
        getBaseContext(),
        "ProviderEnabled,provider:"+provider,
        Toast.LENGTH_SHORT).show();     } @Override public void onStatusChanged(String provider,int status, Bundle extras) { } };   /* 取得GeoPoint的method */ private GeoPoint getGeoByLocation(Location location) { GeoPoint gp = null; try { if (location != null) { double geoLatitude = location.getLatitude()*1E6; double geoLongitude = location.getLongitude()*1E6; gp = new GeoPoint((int) geoLatitude, (int) geoLongitude); } } catch(Exception e) { e.printStackTrace(); } return gp; } /* 取得LocationProvider */ public void getLocationPrivider() {    Criteria mCriteria01 = new Criteria(); mCriteria01.setAccuracy(Criteria.ACCURACY_FINE); mCriteria01.setAltitudeRequired(false); mCriteria01.setBearingRequired(false); mCriteria01.setCostAllowed(true); mCriteria01.setPowerRequirement(Criteria.POWER_LOW); mLocationPrivider = mLocationManager .getBestProvider(mCriteria01, true); mLocation = mLocationManager .getLastKnownLocation(mLocationPrivider);   } /* 设定起点的method */ private void setStartPoint() { int mode=1; drawmap mOverlay = new drawmap(gp1,gp2,mode); List<Overlay> overlays = mMapView.getOverlays(); overlays.add(mOverlay); } /* 设定路线的method */ private void setRoute() { int mode=2; drawmap mOverlay = new drawmap(gp1,gp2,mode); List<Overlay> overlays = mMapView.getOverlays(); overlays.add(mOverlay); } /* 设定终点的method */ private void setEndPoint() { int mode=3; drawmap mOverlay = new drawmap(gp1,gp2,mode); List<Overlay> overlays = mMapView.getOverlays(); overlays.add(mOverlay); } /* 重设Overlay的method */ private void resetOverlay() { List<Overlay> overlays = mMapView.getOverlays(); overlays.clear(); } /* 更新MapView的method */ public void refreshMapView() { mMapView.displayZoomControls(true); MapController myMC = mMapView.getController(); myMC.animateTo(gp2); myMC.setZoom(zoomLevel); mMapView.setSatellite(true); } /* 取得两点间的距离的method */ public double GetDistance(GeoPoint gp1,GeoPoint gp2) { double Lat1r = ConvertDegreeToRadians(gp1.getLatitudeE6()/1E6); double Lat2r = ConvertDegreeToRadians(gp2.getLatitudeE6()/1E6); double Long1r= ConvertDegreeToRadians(gp1.getLongitudeE6()/1E6); double Long2r= ConvertDegreeToRadians(gp2.getLongitudeE6()/1E6); /* 地球半径(KM) */ double R = 6371; double d = Math.acos(Math.sin(Lat1r)*Math.sin(Lat2r)+ Math.cos(Lat1r)*Math.cos(Lat2r)* Math.cos(Long2r-Long1r))*R; return d*1000; }
  private double ConvertDegreeToRadians(double degrees) { return (Math.PI/180)*degrees; } /* format移动距离的method */ public String format(double num) { NumberFormat formatter = new DecimalFormat("###"); String s=formatter.format(num); return s; } @Override protected boolean isRouteDisplayed() { return false; }
}