获取手机信号强度

要想获取信号强度，需要加入权限：

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

AndroidManifest.xml

< ?xml version="1.0" encoding="utf-8"?> <manifest xmlns:android="http://schemas.android.com/apk/res/android"       package="Firstdroid.Tutorial.GetGsmSignalStrength"       android:versionCode="1"       android:versionName="1.0">     <application android:icon="@drawable/icon" android:label="@string/app_name">         <activity android:name=".GetGsmSignalStrength"                   android:label="@string/app_name">             <intent -filter>                 <action android:name="android.intent.action.MAIN" />                 <category android:name="android.intent.category.LAUNCHER" />             </intent>         </activity>      </application>     <uses -sdk android:minSdkVersion="4" />     <uses -permission android:name="android.permission.CHANGE_NETWORK_STATE"></uses> </manifest>

import android.app.Activity; import android.content.Context; import android.os.Bundle; import android.telephony.PhoneStateListener; import android.telephony.SignalStrength; import android.telephony.TelephonyManager; import android.widget.Toast;public class GetGsmSignalStrength extends Activity {    /* This variables need to be global, so we can used them onResume and onPause method to       stop the listener */    TelephonyManager        Tel;    MyPhoneStateListener    MyListener;     /** Called when the activity is first created. */     @Override     public void onCreate(Bundle savedInstanceState)     {         super.onCreate(savedInstanceState);         setContentView(R.layout.main);          /* Update the listener, and start it */         MyListener   = new MyPhoneStateListener();         Tel       = ( TelephonyManager )getSystemService(Context.TELEPHONY_SERVICE);       Tel.listen(MyListener ,PhoneStateListener.LISTEN_SIGNAL_STRENGTHS);     }      /* Called when the application is minimized */     @Override    protected void onPause()     {       super.onPause();       Tel.listen(MyListener, PhoneStateListener.LISTEN_NONE);    }      /* Called when the application resumes */    @Override    protected void onResume()    {       super.onResume();       Tel.listen(MyListener,PhoneStateListener.LISTEN_SIGNAL_STRENGTHS);    }/* —————————– */     /* Start the PhoneState listener */    /* —————————– */     private class MyPhoneStateListener extends PhoneStateListener     {       /* Get the Signal strength from the provider, each tiome there is an update  从得到的信号强度,每个tiome供应商有更新*/       @Override       public void onSignalStrengthsChanged(SignalStrength signalStrength)       {          super.onSignalStrengthsChanged(signalStrength);          Toast.makeText(getApplicationContext(), "Go to Firstdroid!!! GSM Cinr = "             + String.valueOf(signalStrength.getGsmSignalStrength()), Toast.LENGTH_SHORT).show();       }      };/* End of private Class */  }/* GetGsmSignalStrength */