Get number of available cores and cpu info

The method Runtime.availableProcessors() returns the number of processor cores available to the VM.

And the /proc/cpuinfo hold infoprmation about the CPU, you can read it as text file.

Example:

package com.example.androidcpuinfo;

import java.io.BufferedReader;
import java.io.FileNotFoundException;
import java.io.FileReader;
import java.io.IOException;

import android.support.v7.app.ActionBarActivity;
import android.os.Bundle;
import android.widget.TextView;

public class MainActivity extends ActionBarActivity {

 TextView cores, cpuinfo;
 
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        cores = (TextView)findViewById(R.id.cores);
        cpuinfo = (TextView)findViewById(R.id.cpuinfo);
        
        Runtime runtime = Runtime.getRuntime();
        int availableProcessors = runtime.availableProcessors();
        cores.setText("You have " + availableProcessors + " availableProcessors");
        
        //Read text file "/proc/cpuinfo"
        String file_cpuinfo = "/proc/cpuinfo";
        String info = "";
        try {
   FileReader fileReader = new FileReader(file_cpuinfo);
   BufferedReader bufferReader = new BufferedReader(fileReader);

   String line;
         try {
    while((line = bufferReader.readLine()) != null)
    {
     info += line + "\n";
    }
    cpuinfo.setText(info);
   } catch (IOException e) {
    // TODO Auto-generated catch block
    e.printStackTrace();
   }
         
  } catch (FileNotFoundException e) {
   // TODO Auto-generated catch block
   e.printStackTrace();
  }
    }

}

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical"
    android:paddingBottom="@dimen/activity_vertical_margin"
    android:paddingLeft="@dimen/activity_horizontal_margin"
    android:paddingRight="@dimen/activity_horizontal_margin"
    android:paddingTop="@dimen/activity_vertical_margin"
    tools:context="com.example.androidcpuinfo.MainActivity" >

    <TextView
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="android-coding.blogspot.com"
        android:textSize="24dp"
        android:textStyle="bold" />

    <TextView
        android:id="@+id/cores"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:textSize="20dp"
        android:textStyle="italic" />

    <ScrollView
        android:layout_width="match_parent"
        android:layout_height="match_parent" >

        <TextView
            android:id="@+id/cpuinfo"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content" />
    </ScrollView>

</LinearLayout>

Create mirror bitmap using Matrix

package com.example.androidmirrorimage;

import android.support.v7.app.ActionBarActivity;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.graphics.Matrix;
import android.os.Bundle;
import android.widget.ImageView;

public class MainActivity extends ActionBarActivity {

 ImageView image1, image2;

 @Override
 protected void onCreate(Bundle savedInstanceState) {
  super.onCreate(savedInstanceState);
  setContentView(R.layout.activity_main);
  image1 = (ImageView) findViewById(R.id.image1);
  image2 = (ImageView) findViewById(R.id.image2);

  Bitmap bm = BitmapFactory.decodeResource(getResources(),
    R.drawable.ic_launcher);
  
  image1.setImageBitmap(bm);
  image2.setImageBitmap(getMirrorBitmap(bm));

 }

 private Bitmap getMirrorBitmap(Bitmap src) {

  Matrix matrix = new Matrix();
  matrix.preScale(1, -1);
  Bitmap result = Bitmap.createBitmap(
    src, 0, 0, src.getWidth(), src.getHeight(), matrix, false);
  return result;
 }
}

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical"
    android:paddingBottom="@dimen/activity_vertical_margin"
    android:paddingLeft="@dimen/activity_horizontal_margin"
    android:paddingRight="@dimen/activity_horizontal_margin"
    android:paddingTop="@dimen/activity_vertical_margin"
    tools:context="com.example.androidmirrorimage.MainActivity" >

    <TextView
        android:id="@+id/title"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="android-coding.blogspot.com"
        android:textSize="28dp"
        android:textStyle="bold" />

    <ImageView
        android:id="@+id/image1"
        android:layout_width="match_parent"
        android:layout_height="0dp"
        android:layout_weight="1" />

    <ImageView
        android:id="@+id/image2"
        android:layout_width="match_parent"
        android:layout_height="0dp"
        android:layout_weight="1" />

</LinearLayout>

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Custom ImageView to show touched portion only

Here is a custom ImageView (TouchImageView), override onTouchEvent(MotionEvent event) and onDraw(Canvas canvas) methods, to make it display the touched portion only.

package com.example.androidtouchimageview;

import android.content.Context;
import android.graphics.Bitmap;
import android.graphics.BitmapShader;
import android.graphics.Canvas;
import android.graphics.Paint;
import android.graphics.Shader;
import android.util.AttributeSet;
import android.view.MotionEvent;
import android.widget.ImageView;

public class TouchImageView extends ImageView {

 private float radius = 0;
 private Paint paint = null;

 private float x;
 private float y;
 private boolean touched = false;

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

 public TouchImageView(Context context, AttributeSet attrs) {
  super(context, attrs);
  // TODO Auto-generated constructor stub
 }

 public TouchImageView(Context context, AttributeSet attrs, int defStyleAttr) {
  super(context, attrs, defStyleAttr);
  // TODO Auto-generated constructor stub
 }

 @Override
 public boolean onTouchEvent(MotionEvent event) {
  int action = event.getAction();
  touched = (action == MotionEvent.ACTION_DOWN 
    || action == MotionEvent.ACTION_MOVE);
  x = event.getX();
  y = event.getY();
  
  int w = getWidth();
  int h = getHeight();
  if(w>=h){
   radius = h * event.getSize();
  }else{
   radius = w * event.getSize();
  }
  
  invalidate();
  return true;
 }

 @Override
 protected void onDraw(Canvas canvas) {
  if (paint == null) {
   Bitmap bm = Bitmap.createBitmap(
    getWidth(), 
    getHeight(),
    Bitmap.Config.ARGB_8888);
   Canvas originalCanvas = new Canvas(bm);
   super.onDraw(originalCanvas);

   Shader shader = new BitmapShader(bm, 
    Shader.TileMode.CLAMP,
    Shader.TileMode.CLAMP);

   paint = new Paint();
   paint.setShader(shader);
  }

  canvas.drawColor(getSolidColor());
  if (touched) {
   canvas.drawCircle(x, y, radius, paint);
  }
 }

}

Layout

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:paddingBottom="@dimen/activity_vertical_margin"
    android:paddingLeft="@dimen/activity_horizontal_margin"
    android:paddingRight="@dimen/activity_horizontal_margin"
    android:paddingTop="@dimen/activity_vertical_margin"
    android:orientation="vertical"
    tools:context="com.example.androidtouchimageview.MainActivity" >

    <TextView
        android:id="@+id/title"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="android-coding.blogspot.com"
        android:textSize="28dp"
        android:textStyle="bold" />
    
    <com.example.androidtouchimageview.TouchImageView
        android:id="@+id/image1"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:src="@drawable/ic_launcher" />
    
    <com.example.androidtouchimageview.TouchImageView
        android:id="@+id/image2"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:src="@drawable/ic_launcher" />

</LinearLayout>

Implement color animation with ValueAnimator

To implement color animation with ValueAnimator:

package com.example.valueanimatorofcolor;

import com.example.objectanimatorofargb.R;

import android.animation.ArgbEvaluator;
import android.animation.ObjectAnimator;
import android.animation.ValueAnimator;
import android.app.Activity;
import android.os.Bundle;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.ImageView;
import android.widget.TextView;

public class MainActivity extends Activity {

 TextView title;
 Button btnStart;
 ImageView image;

 @Override
 protected void onCreate(Bundle savedInstanceState) {
  super.onCreate(savedInstanceState);
  setContentView(R.layout.activity_main);
  title = (TextView) findViewById(R.id.title);
  image = (ImageView) findViewById(R.id.image);
  btnStart = (Button) findViewById(R.id.start);
  
  btnStart.setOnClickListener(new OnClickListener(){

   @Override
   public void onClick(View v) {
    startColorAnimation(image);
   }});
 }
 
 private void startColorAnimation(View view){
  //int colorStart = 0xFFffffff;
  int colorStart = view.getSolidColor();
  int colorEnd   = 0xFF000000;

  ValueAnimator colorAnim = ObjectAnimator.ofInt(
    view, "backgroundColor", colorStart, colorEnd);
  colorAnim.setDuration(2000);
  colorAnim.setEvaluator(new ArgbEvaluator());
  colorAnim.setRepeatCount(1);
  colorAnim.setRepeatMode(ValueAnimator.REVERSE);
  colorAnim.start();
 }

}

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical"
    android:paddingBottom="@dimen/activity_vertical_margin"
    android:paddingLeft="@dimen/activity_horizontal_margin"
    android:paddingRight="@dimen/activity_horizontal_margin"
    android:paddingTop="@dimen/activity_vertical_margin"
    tools:context="com.example.valueanimatorofcolor.MainActivity" >

    <TextView
        android:id="@+id/title"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="android-coding.blogspot.com"
        android:textSize="28dp"
        android:textStyle="bold" />

    <Button
        android:id="@+id/start"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:text="Start Animation" />

    <ImageView
        android:id="@+id/image"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:src="@drawable/ic_launcher" />

</LinearLayout>