Silent Mode Toggle App

Java Part : 

package com.example.silent.mode.toggle;

import android.os.Bundle;
import android.app.Activity;
import android.widget.ImageView;
import android.widget.TextView;
import android.widget.Toast;
import android.util.Log;
import android.view.View;
import android.graphics.drawable.Drawable;
import android.media.AudioManager;
import android.widget.Button;

public class MainActivity extends Activity {

 private AudioManager mAudioManager;
 private boolean mPhoneIsSilent;
 Button normal, silent;
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        
        super.onCreate(savedInstanceState);
        mAudioManager = (AudioManager)getSystemService(AUDIO_SERVICE);
        checkIfPhoneIsSilent();
        setButtonClickListener();
        Log.d("SilentModeApp", "This is a test");
        
    }    
        
    // Does not detect phones current status and just displays to activate Silent Mode 
    
        private void setButtonClickListener() {
        final TextView txt = (TextView) findViewById(R.id.txt1); 
        final Button toggleButton = (Button)findViewById(R.id.silent);
        toggleButton.setOnClickListener(new View.OnClickListener() {
         public void onClick(View v) {
          
         if (mPhoneIsSilent) {
          //change back to normal mode
          
          mAudioManager.setRingerMode(AudioManager.RINGER_MODE_VIBRATE);
          mPhoneIsSilent = false;
          toggleButton.setText("Activate Silent Mode");
          txt.setText("Mobile Is In Vibration Mode");
          Toast.makeText(getBaseContext(), "Vibration Mode Activated", 
                  Toast.LENGTH_LONG).show();
         }
          else
          {
           //change to silent mode
           mAudioManager.setRingerMode(AudioManager.RINGER_MODE_SILENT);
           mPhoneIsSilent = true;
           toggleButton.setText("Activate Vibration Mode");
           txt.setText("Mobile Is In Silent Mode");
           Toast.makeText(getBaseContext(), "Silent Mode Activated",
                            Toast.LENGTH_LONG).show();
          }
         // Now toggle the UI again
         toggleUi(); 
         }
         });
    }
        private void checkIfPhoneIsSilent() {
         int ringermode = mAudioManager.getRingerMode();
         if (ringermode == AudioManager.RINGER_MODE_SILENT) {
          mPhoneIsSilent = true;
         }
         else
         {
          mPhoneIsSilent = false;
         }
        }
        private void toggleUi() {
         ImageView imageView = (ImageView) findViewById(R.id.phone_icon);
         Drawable newPhoneImage;
         if (mPhoneIsSilent){
          newPhoneImage = 
          getResources().getDrawable(R.drawable.phone_silent);
        }
        else
        {
          newPhoneImage = 
           getResources().getDrawable(R.drawable.vibration_on);
        
        }
         imageView.setImageDrawable(newPhoneImage);
    
}
@Override      
protected void onResume() {
 super.onResume();
 checkIfPhoneIsSilent();
 toggleUi();
 
}
}

Here is the XML part

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    android:background="#ffffff"
    android:orientation="vertical" >

    <ImageView
        android:id="@+id/phone_icon"
        android:layout_width="wrap_content"
        android:layout_height="0dip"
  android:layout_weight="1"
        android:layout_gravity="center"
        android:layout_marginTop="12dp"
        android:src="@drawable/phone_silent" />

    <Button
        android:id="@+id/silent"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_gravity="center"
        android:layout_marginTop="35dp"
        android:text="@string/silent_on" />
    
    <TextView 
        android:id="@+id/txt1"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_gravity="center"
        android:layout_marginTop="45dp"
      />
       

    </LinearLayout>