定位(2):选择最好的provider

1.获取最佳的Location Provider

GPS    NETWORK    PASSIVE

 

 

在AndroidManifest.xml中声明权限：

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

 

 activity_main.xml

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:orientation="vertical"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    >
<TextView  
    android:layout_width="fill_parent" 
    android:layout_height="wrap_content" 
    android:text="@string/hello"
    />
    <Button 
    	android:id="@+id/ScanProvidersButton"
    	android:layout_width="fill_parent"
    	android:layout_height="wrap_content"
    	android:text="测试当前设备的Providers"/>
    <Button 
    	android:id="@+id/bestProviderButton"
    	android:layout_width="fill_parent"
    	android:layout_height="wrap_content"
    	android:text="最好的Provider"/>
</LinearLayout>

 

 Criteria:可以设置一系列的查询条件，用于查询当前设备中符合条件的Location Provider

具体参看android 帮助文档http://developer.android.com/reference/android/location/Criteria.html

 

import java.util.Iterator;
import java.util.List;
import android.app.Activity;
import android.content.Context;
import android.location.Criteria;
import android.location.LocationManager;
import android.os.Bundle;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;

public class MainActivity extends Activity {
	private Button scanProvider = null;
	private Button bestProvider = null;
	private LocationManager locationManager = null;
    /** Called when the activity is first created. */
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);
        
        locationManager = (LocationManager)MainActivity.this.getSystemService(Context.LOCATION_SERVICE);
        scanProvider = (Button)findViewById(R.id.ScanProvidersButton);
        bestProvider = (Button)findViewById(R.id.bestProviderButton);
        
        scanProvider.setOnClickListener(new providerOnClickListener());  
        bestProvider.setOnClickListener(new bestproviderOnClickListener());
    }
    
    private class providerOnClickListener implements OnClickListener{
    	@Override
		public void onClick(View arg0) {
			//得到所有的provider，返回的是一个存放String的List
			List<String> providers = locationManager.getAllProviders();
			System.out.println("providers:");
			for(Iterator<String> it = providers.iterator();it.hasNext();){
				String provider = (String)it.next();
				System.out.println("============="+provider);
			}
			
		}
    	
    }
    
    private class bestproviderOnClickListener implements OnClickListener{
    	@Override
		public void onClick(View arg0) {
			Criteria criteria = new Criteria();
			//设置查找最好的provider的过滤条件
			criteria.setAccuracy(Criteria.ACCURACY_FINE);
			criteria.setSpeedRequired(false);
			criteria.setCostAllowed(false);
			//获得最好的provider，第二个参数表示是否考虑provider可用
			String provider = locationManager.getBestProvider(criteria, false);
			System.out.println("best provider ---> "+provider);
			
			
		}
    	
    }
}

  

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