Create an application to draw line on the screen as user drag his finger.

Pro20Activity.java

package ps.pro20;

import android.app.Activity;
import android.os.Bundle;
public class Pro20Activity extends Activity {
    /**
     *  www.master-gtu.blogspot.com
     *  pankaj sharma(8460479175),
     *  chavda vijay(8460420769) 
     */
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(new ScreenActivity(this));
    }
}

ScreenActivity.java

package ps.pro20;

import android.content.Context;
import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.Paint;
import android.graphics.Path;
import android.view.MotionEvent;
import android.view.View;
public class ScreenActivity extends View 
{
    /**
     *  www.master-gtu.blogspot.com
     *  pankaj sharma(8460479175),
     *  chavda vijay(8460420769) 
     */
 Paint paintBrush=new Paint(Paint.ANTI_ALIAS_FLAG);
 Path path=new Path();
 
 public ScreenActivity(Context context) {
  super(context);  
  paintBrush.setColor(Color.RED);
  paintBrush.setStrokeWidth(5);
  paintBrush.setStyle(Paint.Style.STROKE);
 }
 @Override
 protected void onDraw(Canvas canvas) {
  // TODO Auto-generated method stub
 super.onDraw(canvas);
  canvas.drawPath(path, paintBrush);
 }
 @Override
 public boolean onTouchEvent(MotionEvent event) {
  // TODO Auto-generated method stub
  super.onTouchEvent(event);
  
  //------getting position-------
  
  float x=event.getX();
  float y=event.getY();
  
  switch(event.getAction())
  {
   case MotionEvent.ACTION_DOWN:
    path.moveTo(x, y);
    return true;
    
   case MotionEvent.ACTION_MOVE:
    path.lineTo(x, y);
    break;
  }
  invalidate();
  return true; 
 }
}