編輯:關於Android編程
android自帶gps定位功能相信大家都不會太陌生了,都有所涉及。簡單的寫了一個示例程序,獲取經緯度還有其它相關數據的代碼,還有其他相關的知識,比如直接跳轉到打開系統gps設置的界面。還有一個bug的處理,異常信息:Incomplete location object, missing timestamp or accuracy
package com.example.locationexample; import android.location.Location; import android.location.LocationListener; import android.location.LocationManager; import android.os.Build; import android.os.Bundle; import android.os.SystemClock; import android.util.Log; import android.widget.TextView; import android.annotation.TargetApi; import android.app.Activity; import android.content.Context; public class MainActivity extends Activity { LocationManager mLocationManager; Location mlocation; TextView mTextView; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); mTextView = (TextView)findViewById(R.id.textView1); getLocation(); // mlocation.setElapsedRealtimeNanos(SystemClock.elapsedRealtimeNanos()); // mLocationManager.setTestProviderLocation(LocationManager.GPS_PROVIDER, mlocation); } public Location getLocation(){ mLocationManager = (LocationManager)getSystemService(Context.LOCATION_SERVICE); mlocation = mLocationManager.getLastKnownLocation(LocationManager.GPS_PROVIDER); if (mlocation == null) { mlocation = mLocationManager.getLastKnownLocation(LocationManager.NETWORK_PROVIDER); } mLocationManager.requestLocationUpdates(LocationManager.GPS_PROVIDER, 100, 0, mLocationListener); return mlocation; } LocationListener mLocationListener = new LocationListener() { @TargetApi(17) @Override public void onLocationChanged(Location mlocal) { if(mlocal == null) return; String strResult = "getAccuracy:" + mlocal.getAccuracy() + "\r\n" + "getAltitude:" + mlocal.getAltitude() + "\r\n" + "getBearing:" + mlocal.getBearing() + "\r\n" + "getElapsedRealtimeNanos:" + String.valueOf(mlocal.getElapsedRealtimeNanos()) + "\r\n" + "getLatitude:" + mlocal.getLatitude() + "\r\n" + "getLongitude:" + mlocal.getLongitude() + "\r\n" + "getProvider:" + mlocal.getProvider()+ "\r\n" + "getSpeed:" + mlocal.getSpeed() + "\r\n" + "getTime:" + mlocal.getTime() + "\r\n"; Log.i("Show", strResult); if (mTextView != null) { mTextView.setText(strResult); } } @Override public void onProviderDisabled(String arg0) { } @Override public void onProviderEnabled(String arg0) { } @Override public void onStatusChanged(String provider, int event, Bundle extras) { } }; }
權限如下:
LocationManager.GPS_PROVIDER是gps提供,100是時間,多久刷新一次,0是距離,如果你不動的話,測試最好寫0
mLocationListener是接口啦,數據就是那裡來的。
如果你使用mLocationManager.setTestProviderLocation(LocationManager.GPS_PROVIDER, mlocation);這行代碼報出下面的堆棧錯誤信息
java.lang.IllegalArgumentException: Incomplete location object, missing timestamp or accuracy? Location[gps 23.126704,113.365648 acc=1 et=?!? alt=-7.422 vel=0.008333334 bear=237.76]
方法一:
主要是這句,location.setElapsedRealtimeNanos(SystemClock.elapsedRealtimeNanos());,其實加上這句就可以了。
例如:
@SuppressLint("NewApi") private Location getLoc(String provider) { Location location = new Location(provider); location.setLatitude(lat); location.setLongitude(lng); location.setAltitude(altitude); location.setBearing(bearing); location.setSpeed(speed); location.setAccuracy(accuracy); location.setTime(System.currentTimeMillis()); location.setElapsedRealtimeNanos(SystemClock.elapsedRealtimeNanos()); return location; }主要是這句,location.setElapsedRealtimeNanos(SystemClock.elapsedRealtimeNanos());,其實加上這句就可以了。如下
mlocation.setElapsedRealtimeNanos(SystemClock.elapsedRealtimeNanos()); mLocationManager.setTestProviderLocation(LocationManager.GPS_PROVIDER, mlocation);
try { Method method = Location.class.getMethod("makeComplete"); if (method != null) { method.invoke(localLocation); } } catch (NoSuchMethodException e) { e.printStackTrace(); } catch (Exception e) { e.printStackTrace(); }
源碼如下:
/** * Helper to fill incomplete fields. * * Used to assist in backwards compatibility with * Location objects received from applications. * * @see #isComplete * @hide */ public void makeComplete() { if (mProvider == null) mProvider = "?"; if (!mHasAccuracy) { mHasAccuracy = true; mAccuracy = 100.0f; } if (mTime == 0) mTime = System.currentTimeMillis(); if (mElapsedRealtimeNanos == 0) mElapsedRealtimeNanos = SystemClock.elapsedRealtimeNanos(); }
建議使用第一個方法。
//獲取是否已打開自身GPS public boolean isGpsEnable() { String providers = Settings.Secure.getString(mContext.getContentResolver(), Settings.Secure.LOCATION_PROVIDERS_ALLOWED); if (providers.contains(LocationManager.GPS_PROVIDER)) { return true; } else { return false; } }
Intent callGPSSettingIntent = new Intent( android.provider.Settings.ACTION_LOCATION_SOURCE_SETTINGS); this.startActivity(callGPSSettingIntent);
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