Detect Touch Event part III - get touch pressure and size

The MotionEvent object retured with pressure and size of touching. It can be get using getPressure() and getSize() method. The code in last post "Detect Touch Event, test on Custom View; part II" is further modified to show touching pressure and size in color and radius.

package com.TestSingleTouch;

import android.app.Activity;
import android.content.Context;
import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.Paint;
import android.os.Bundle;
import android.view.MotionEvent;
import android.view.View;
import android.widget.LinearLayout;
import android.widget.TextView;

public class TestSingleTouch extends Activity {
 
   public class TouchView extends View {
    
    private Paint paint = new Paint(Paint.ANTI_ALIAS_FLAG);
    private float x, y;
    boolean touching = false;
    
    float pressure = 0; //Touch pressure
    float size = 0;  //Touch size
    final static float PRESET_PRESSURE = 0xFF;
    final static float PRESET_SIZE = 300;

  public TouchView(Context context) {
   super(context);
   // TODO Auto-generated constructor stub
  }

  @Override
  protected void onDraw(Canvas canvas) {
   // TODO Auto-generated method stub
   if(touching){
    
    //paint.setStyle(Paint.Style.STROKE);
    //paint.setStrokeWidth(1);
    //paint.setColor(Color.WHITE);
    //canvas.drawCircle(x, y, 50f, paint);
    
    paint.setStyle(Paint.Style.FILL_AND_STROKE);
    paint.setStrokeWidth(1);
    paint.setColor(0xFF000000
      + ((int)(PRESET_PRESSURE * pressure) <<16)
      + ((int)(PRESET_PRESSURE * pressure) << 8)
      + (int)(PRESET_PRESSURE * pressure));
    canvas.drawCircle(x, y, (PRESET_SIZE * size), paint);
   }
  }

  @Override
  protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
   // TODO Auto-generated method stub
   setMeasuredDimension(MeasureSpec.getSize(widthMeasureSpec),
         MeasureSpec.getSize(heightMeasureSpec));
  }

  @Override
  public boolean onTouchEvent(MotionEvent event) {
   // TODO Auto-generated method stub
   
   pressure = event.getPressure();
   if(pressure > 1){
    pressure = 1;
   }
   
   size =event.getSize();
   
   String act;

   int action = event.getAction();
   switch(action){
   case MotionEvent.ACTION_MOVE:
    act = "ACTION_MOVE\n";
    x = event.getX();
    y = event.getY();

    touching = true;
    break;
   case MotionEvent.ACTION_DOWN:
    act = "ACTION_DOWN\n";
    x = event.getX();
    y = event.getY();
    
    touching = true;
    break;
   case MotionEvent.ACTION_UP:
    act = "ACTION_UP\n";
    touching = false;
    break;
   default:
    act = "XXX\n";
    touching = false;
   }
   
   act += event.toString();
   textView.setText(act);
   
   invalidate();
   return true;
  }

 }
  
   TextView textView;

 /** Called when the activity is first created. */
   @Override
   public void onCreate(Bundle savedInstanceState) {
       super.onCreate(savedInstanceState);
       //setContentView(new TouchView(this));
      
       textView = new TextView(this);
       textView.setText("Waiting");
       TouchView touchView = new TouchView(this);
       LinearLayout mainScreen = new LinearLayout(this);
       mainScreen.setOrientation(LinearLayout.VERTICAL);
       mainScreen.addView(textView);
       mainScreen.addView(touchView);
       setContentView(mainScreen);

   }
  
}

Next:
- Detect Touch Event part IV - get touch area

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