To Find the file extension using JAVA

String extension;


int dotPos = filenameExtension.lastIndexOf(".");

extension = filenameExtension.substring(dotPos);

Combining both view with xml layout.

package com.android.murthy;

import android.app.Activity;
import android.content.Context;
import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.Paint;
import android.graphics.Rect;
import android.graphics.RectF;
import android.os.Bundle;
import android.util.Log;
import android.view.View;
import android.view.View.OnClickListener;
import android.view.ViewGroup.LayoutParams;
import android.widget.Button;
import android.widget.EditText;

public class Dynamic extends Activity {
    /** Called when the activity is first created. */
    Inner inner;
    EditText preview_val;
    Button show_prev;
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);
        inner = new Inner(this);
      //  setContentView(inner);
        LayoutParams params = new LayoutParams(150,105);
        addContentView(inner, params);
        preview_val = (EditText) findViewById(R.id.prev_value);
        show_prev = (Button) findViewById(R.id.previewBtn);
        show_prev.setOnClickListener(new OnClickListener() {
          
            @Override
            public void onClick(View v) {
                // TODO Auto-generated method stub
                String value = preview_val.getText().toString();
                Log.i("edit_txt value",value);
            }
        });
      
      
      
      
    }
    private class Inner extends View{

        public Inner(Context context) {
            super(context);
            // TODO Auto-generated constructor stub
        }
        @Override
        protected void onDraw(Canvas canvas) {
            // TODO Auto-generated method stub
            super.onDraw(canvas);
            Rect rect = new Rect(10, 40, 60, 80);
            Paint paint = new Paint();
            paint.setStyle(Paint.Style.FILL);
            paint.setColor(Color.RED);
           // canvas.drawColor(Color.GREEN);
            canvas.drawRect(rect, paint);
        }
    }
}
 main.xml

    android:orientation="vertical"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    android:background="#FFFFFF"
   
    >


                android:layout_height="fill_parent" >

          android:layout_marginLeft="200dp"
          android:text="ZOOM (%)"
          android:id="@+id/zoom_txt"
          android:layout_width="wrap_content"
          android:layout_height="wrap_content"
          android:textColor="#000000"/>                 

          android:id="@+id/prev_value"
          android:layout_width="100dp"
          android:layout_height="wrap_content"
          android:layout_marginLeft="200dp"
          android:maxLines="1"/>