Android Studio bug versioncode versionname signed apk issue

public class MainActivity extends Activity {
	
	@Override
	protected void onCreate(Bundle savedInstanceState) {
		super.onCreate(savedInstanceState);
		setContentView(new SampleView(this));
	}

	private static class SampleView extends View {

		// CONSTRUCTOR
		public SampleView(Context context) {
			super(context);
			setFocusable(true);

		}
		@Override
		protected void onDraw(Canvas canvas) {
			Paint paint = new Paint();
			
			canvas.drawColor(Color.GREEN);
            
           Bitmap b = Bitmap.createBitmap(200, 200, Bitmap.Config.ALPHA_8);
           Canvas c = new Canvas(b);
           RectF rectF = new RectF();
           rectF.set(5,5,150,150);
           c.drawRoundRect(rectF, 10, 10, paint);
           
            paint.setColor(Color.RED);
           
           canvas.drawBitmap(b, 10,10, paint);
		}

	}
}

import java.util.Collections;
import java.util.LinkedList;
import java.util.List;

public class MainClass {
	public static void main(String[] arg) {
		String[] arrayOfString = {"nothing", "Hello", "people"
				, "bye-bye", "hello", "world!", "End" };
		   List<String> arrayList = new LinkedList<String>();
            for(String s: arrayOfString)
		     arrayList.add(s);

		    Collections.shuffle(arrayList);

		    System.out.println(arrayList);
		    
		  }
}
/*
[hello, world!, bye-bye, nothing, people, End, Hello]
*/

public class MainActivity extends Activity implements OnClickListener {

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);
        
        LinearLayout layout = (LinearLayout) findViewById(R.id.layout);
            RadioGroup radioGroup = new RadioGroup(this);
            
            LinearLayout.LayoutParams p = new LinearLayout.LayoutParams(
                    LinearLayout.LayoutParams.FILL_PARENT,
                    LinearLayout.LayoutParams.WRAP_CONTENT
            );
            layout.addView(radioGroup, p);

            RadioButton radioButtonView = new RadioButton(this);
            radioButtonView.setText("RadioButton");
            radioButtonView.setOnClickListener(this);
            radioGroup.addView(radioButtonView, p);
            
            RadioButton radioButtonView2 = new RadioButton(this);
            radioButtonView2.setText("RadioButton2");
            radioButtonView2.setOnClickListener(mThisButtonListener);
            radioGroup.addView(radioButtonView2, p);
        
    }
    
    public void onClick(View view) {
    	 try {
    	  String s = ((RadioButton) view).getText().toString();
    	  Toast.makeText(MainActivity.this, "This is: " + s,
    			  Toast.LENGTH_LONG).show();
    	 }
    	 catch (Exception e1) {
    	   e1.printStackTrace();
    	 }
    	}
    
    private OnClickListener mThisButtonListener = new OnClickListener() {
        public void onClick(View v) {
        	String s = ((RadioButton) v).getText().toString();
        	Toast.makeText(MainActivity.this, "Hello from 2!" + s,
        			Toast.LENGTH_LONG).show();
        }
    };

}

<resources>
    <string-array name="colors">
        <item>red</item>
        <item>orange</item>
        <item>yellow</item>
        <item>green</item>
        <item>blue</item>
    </string-array>
</resources>

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