Android Contacts List

Here useful information  is How to Display your contacts in  List View
we want get contacts from  ContactsContract means (The contract between the contacts provider and applications),  your Contacts geting from Cursor 

This Is Code for Getting All contacts from Cursor

Cursor phones = getContentResolver().query(ContactsContract.CommonDataKinds.Phone.CONTENT_URI, null, null, null, null);

while (phones.moveToNext()) {

String name = phones.getString(phones.getColumnIndex(ContactsContract.CommonDataKinds.Phone.DISPLAY_NAME));  

String phoneNumber = phones.getString(phones.getColumnIndex(ContactsContract.CommonDataKinds.Phone.NUMBER));

ContactBean objContact = new ContactBean();  

objContact.setName(name);  

objContact.setPhoneNo(phoneNumber);  

list.add(objContact);

JAVA TIPS AND LOGICS

1. Conditional Operators

int value1 = 1;

int value2 = 2;

// AND Operator   "&&"

if((value1 == 1) && (value2 == 2))

// here Both statements are true condition is true other wise false
            System.out.println("value1 is 1 AND value2 is 2");

if((value1 == 2) && (value2 == 1))

            System.out.println("value1 is 2 AND value2 is 1");

// OR Operator   "||"

        if((value1 == 1) || (value2 == 1))

         // here Any one statements are true condition is true other wise false

            System.out.println("value1 is 1 OR value2 is 1");

    Output
             value1 is 1 AND value2 is 2
                   value1 is 1 OR  value2 is 1


2. Equality and Relational Operators

    int value1 = 1;

int value2 = 2;

         // Both values are equal this condition true
if (value1 == value2)
System.out.println("value1 == value2");
        // value1 not equal to value2 this condition is true
if (value1 != value2)
System.out.println("value1 != value2");              
if (value1 > value2)
System.out.println("value1 > value2");            
if (value1 < value2)
System.out.println("value1 < value2");
if (value1 <= value2)
System.out.println("value1 <= value2"); 

    Output
               value1 != value2
               value1 < value2
               value1 <= value2

3. Operators

     int result = 1 + 2; // result is now 3
        System.out.println(result);

        result = result - 1; // result is now 2
        System.out.println(result);

        result = result * 2; // result is now 4
        System.out.println(result);

        result = result / 2; // result is now 2
        System.out.println(result);

        result = result + 8; // result is now 10
        System.out.println(result);
        
        result = result % 7; // result is now 3
        System.out.println(result);   

    Output
             3 , 2, 4, 10, 3

4. if and else-if


        int testscore = 76;
        char grade;
        if (testscore >= 90) {
            grade = 'A';
        } else if (testscore >= 80) {
            grade = 'B';
        } else if (testscore >= 70) {
            grade = 'C';
        } else if (testscore >= 60) {
            grade = 'D';
        } else {
            grade = 'F';
        }
        System.out.println("Grade = " + grade);
  
    Output              

                   grade = 'C';

5. Loop While and for

        int count = 0;
        // While loop
        while (count < 11) {          
            System.out.println("Count while: " + count);
            count++;
        }            
           // for loop
            for(int i=0; i<11; i++){
                System.out.println("Count for: " + i);
        }

      Output
           Here Both outputs are same but conditions are different
                   Count while: 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10
                   Count for: 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10

6. for to loop through the array

int[] numbers = { 1,2,3,4,5,6,7,8,9,10 };
        for (int item : numbers) {
            System.out.println("Count is: " + item);
        }

    Output
           Count is: 1, 2, 3, 4, 5, 6, 7, 8, 9, 10

7. Number found in single Array-list(unlabeled break)

     // here number found in specific array list
int[] arrayOfInts =  { 32, 7, 3, 89, 12, 106, 20,  8012, 62, 51 };
       // search number is 12
        int searchfor = 12;
        int i;
        boolean foundIt = false;

        for (i = 0; i < arrayOfInts.length; i++) {
            if (arrayOfInts[i] == searchfor) {
                foundIt = true;
                break;
            }
        }
        if (foundIt) {
            System.out.println("Found " + searchfor + " at index " + i);
        } else {
            System.out.println(searchfor + " not in the array");
        }

      Output
             search number is in array list                     

                   // "Found " search number " at index " index number 

                   // here out put is number 12 this number in index 4
                      Found  12 at index  4

                   // number not found 
                      12  not in the array

8. for loops to search for a value in a two-dimensional array.

int[][] arrayOfInts = {      { 132, 817, 35, 589 },
                                                  { 12, 106, 200, 80 },
                                                  { 522, 12, 94, 150 }
                                          };
       int searchfor = 94;
       int i;
       int j = 0;
       boolean foundIt = false;
   search:
       for (i = 0; i < arrayOfInts.length; i++) {
           for (j = 0; j < arrayOfInts[i].length; j++) {
           
               if (arrayOfInts[i][j] == searchfor) {
                   foundIt = true;
                   break search;
               }
           }
       }
       if (foundIt) {
           System.out.println("Found " + searchfor + " at " + i + ", " + j);
       } else {
           System.out.println(searchfor + " not in the array");
       }

   Output
               // if 94 available in array list
                        Found 94 at 2, 2
                     // if specified number not in array list
                       number(94)  not in the array


9. program increments and find letter count in String.

 

String searchMe   = "peter piper picked a ppppp " +    "peck of pickled peppers";
int max = searchMe.length();
int letterCount = 0;

for (int i = 0; i < max; i++) {
// select specific letter here select "p" letter
if (searchMe.charAt(i) != 'p')
continue;  
letterCount++;
}
System.out.println("Found " + letterCount + " p's in the string."); 

      Output
            Found  14 p's in the string.

Simple free hand Paint with Color Changes using Color Picker

1.MAIN ACTIVITY 


import com.example.simplepaint.PickerDialog.OnColorChangedListener;
import android.app.Activity;
import android.content.Context;
import android.graphics.Bitmap;
import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.Paint;
import android.graphics.Path;
import android.graphics.PorterDuff;
import android.graphics.PorterDuffXfermode;
import android.os.Bundle;
import android.util.DisplayMetrics;
import android.util.Log;
import android.view.MotionEvent;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.RelativeLayout;

public class MainActivity extends Activity {

private RelativeLayout relativelayout;

// Instance variables
private Paint mPaint, mBitmapPaint;
private MyView mView;
private Bitmap mBitmap;
private Canvas mCanvas;
private Path mPath;
private Button ClearPaint, Colorpaint;

@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);

relativelayout = (RelativeLayout) findViewById(R.id.item);


DisplayMetrics metrics = getBaseContext().getResources().getDisplayMetrics();
int w = metrics.widthPixels;
int h = metrics.heightPixels;

System.out.println(" width " + w);
System.out.println(" height " + h);

mView = new MyView(this, w, h);
mView.setDrawingCacheEnabled(true);

mPaint = new Paint();
mPaint.setAntiAlias(true);
mPaint.setDither(true);
mPaint.setColor(Color.GREEN);
mPaint.setStyle(Paint.Style.STROKE);
mPaint.setStrokeJoin(Paint.Join.ROUND);
mPaint.setStrokeCap(Paint.Cap.ROUND);
mPaint.setStrokeWidth(5);

ClearPaint = (Button) findViewById(R.id.ClearPaint);
ClearPaint.setOnClickListener(new OnClickListener() {

public void onClick(View v) {
mBitmap.eraseColor(Color.TRANSPARENT);
mPath.reset();
mView.invalidate();
}
});

Button Colorpaint = (Button) findViewById(R.id.color);
Colorpaint.setOnClickListener(new OnClickListener() {

public void onClick(View v) {

int _color = R.color.red;
new PickerDialog(v.getContext(),new OnColorChangedListener()  {

         public void colorChanged(int color) {
         mPaint.setColor(color);
         Log.i("TAG", "mpaint one" +mPaint);
          }
      }, mPaint.getColor(), _color).show();
     Log.i("TAG", "mpaint two" +mPaint);
}
});    
relativelayout.addView(mView);
}

/*/// color changed function, getting value from ColorPickerDialog ///
public void colorChanged(int color) {
mPaint.setColor(color);
} */

// //////////******************* Pinting view *******************///////////////////

public class MyView extends View {

public MyView(Context c, int w, int h) {
super(c);
mBitmap = Bitmap.createBitmap(w, h, Bitmap.Config.ARGB_8888);
// Bitmap mBitmap =
// Bitmap.createScaledBitmap(originalBitmap,200,200,true);
mCanvas = new Canvas(mBitmap);
mPath = new Path();
mBitmapPaint = new Paint(Paint.DITHER_FLAG);
mBitmapPaint
.setXfermode(new PorterDuffXfermode(PorterDuff.Mode.SRC));
}

@Override
protected void onSizeChanged(int w, int h, int oldw, int oldh) {
super.onSizeChanged(w, h, oldw, oldh);
// mBitmap = Bitmap.createBitmap(bw, bh, Bitmap.Config.ARGB_8888);
// mCanvas = new Canvas(mBitmap);
}

@Override
protected void onDraw(Canvas canvas) {
canvas.drawColor(Color.TRANSPARENT);
canvas.drawBitmap(mBitmap, 0, 0, mBitmapPaint);
canvas.drawPath(mPath, mPaint);
}

// //////************touching evants for painting**************///////
private float mX, mY;
private static final float TOUCH_TOLERANCE = 5;

private void touch_start(float x, float y) {
mPath.reset();
mPath.moveTo(x, y);
mX = x;
mY = y;
}

private void touch_move(float x, float y) {
float dx = Math.abs(x - mX);
float dy = Math.abs(y - mY);
if (dx >= TOUCH_TOLERANCE || dy >= TOUCH_TOLERANCE) {
mPath.quadTo(mX, mY, (x + mX) / 2, (y + mY) / 2);
mX = x;
mY = y;
}
}

private void touch_up() {
mPath.lineTo(mX, mY);
// commit the path to our offscreen
mCanvas.drawPath(mPath, mPaint);
// kill this so we don't double draw
mPath.reset();
}

@Override
public boolean onTouchEvent(MotionEvent event) {
float x = event.getX();
float y = event.getY();
switch (event.getAction()) {
case MotionEvent.ACTION_DOWN:
touch_start(x, y);
invalidate();
break;
case MotionEvent.ACTION_MOVE:
touch_move(x, y);
invalidate();
break;
case MotionEvent.ACTION_UP:
touch_up();
invalidate();
break;
}
return true;
} // end of touch events for image
}// end MyView
}

2.MAIN.XML


<RelativeLayout 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" >

    <RelativeLayout
        android:id="@+id/item"
        android:layout_below="@+id/linear"
        android:layout_width="match_parent"
        android:layout_height="match_parent" >

        <ImageView
            android:id="@+id/imageView"
            android:layout_width="fill_parent"
            android:layout_height="fill_parent"
            android:layout_alignParentLeft="true"
            android:layout_alignParentTop="true"
            android:src="@drawable/cat" />

    </RelativeLayout>

    <LinearLayout
        android:id="@+id/linear"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content" >

        <Button
            android:id="@+id/color"
            android:layout_width="fill_parent"
            android:layout_height="wrap_content"
            android:layout_weight="1"
            android:text="ChangeColor" />

        <Button
            android:id="@+id/ClearPaint"
            android:layout_width="fill_parent"
            android:layout_height="wrap_content"
            android:layout_weight="1"
            android:text="ClearPaint" />
    </LinearLayout>

</RelativeLayout>


 3. COLORPICKERVIEW ACTIVITY

import android.app.Dialog;
import android.content.Context;
import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.LinearGradient;
import android.graphics.Paint;
import android.graphics.Shader;
import android.os.Bundle;
import android.view.MotionEvent;
import android.view.View;

public class PickerDialog extends Dialog {

    public interface OnColorChangedListener {
        void colorChanged(int color);
    }

    private OnColorChangedListener mListener;
    private int mInitialColor, mDefaultColor;
    //private String mKey;

private static class ColorPickerView extends View {

private Paint mPaint;
private float mCurrentHue = 0;
private int mCurrentX = 0, mCurrentY = 0;
private int mCurrentColor, mDefaultColor;
private final int[] mHueBarColors = new int[258];
private int[] mMainColors = new int[65536];
private OnColorChangedListener mListener;

ColorPickerView(Context c, OnColorChangedListener l, int color, int defaultColor)  {
super(c);
mListener = l;
mDefaultColor = defaultColor;

// Get the current hue from the current color and update the main color field
float[] hsv = new float[3];
Color.colorToHSV(color, hsv);
mCurrentHue = hsv[0];
updateMainColors();

mCurrentColor = color;

// Initialize the colors of the hue slider bar
int index = 0;
for (float i=0; i<256; i += 256/42) // Red (#f00) to pink (#f0f)
{
mHueBarColors[index] = Color.rgb(255, 0, (int) i);
index++;
}
for (float i=0; i<256; i += 256/42) // Pink (#f0f) to blue (#00f)
{
mHueBarColors[index] = Color.rgb(255-(int) i, 0, 255);
index++;
}
for (float i=0; i<256; i += 256/42) // Blue (#00f) to light blue (#0ff)
{
mHueBarColors[index] = Color.rgb(0, (int) i, 255);
index++;
}
for (float i=0; i<256; i += 256/42) // Light blue (#0ff) to green (#0f0)
{
mHueBarColors[index] = Color.rgb(0, 255, 255-(int) i);
index++;
}
for (float i=0; i<256; i += 256/42) // Green (#0f0) to yellow (#ff0)
{
mHueBarColors[index] = Color.rgb((int) i, 255, 0);
index++;
}
for (float i=0; i<256; i += 256/42) // Yellow (#ff0) to red (#f00)
{
mHueBarColors[index] = Color.rgb(255, 255-(int) i, 0);
index++;
}

// Initializes the Paint that will draw the View
mPaint = new Paint(Paint.ANTI_ALIAS_FLAG);
mPaint.setTextAlign(Paint.Align.CENTER);
mPaint.setTextSize(12);
}

// Get the current selected color from the hue bar
private int getCurrentMainColor()
{
int translatedHue = 255-(int)(mCurrentHue*255/360);
int index = 0;
for (float i=0; i<256; i += 256/42)
{
if (index == translatedHue)
return Color.rgb(255, 0, (int) i);
index++;
}
for (float i=0; i<256; i += 256/42)
{
if (index == translatedHue)
return Color.rgb(255-(int) i, 0, 255);
index++;
}
for (float i=0; i<256; i += 256/42)
{
if (index == translatedHue)
return Color.rgb(0, (int) i, 255);
index++;
}
for (float i=0; i<256; i += 256/42)
{
if (index == translatedHue)
return Color.rgb(0, 255, 255-(int) i);
index++;
}
for (float i=0; i<256; i += 256/42)
{
if (index == translatedHue)
return Color.rgb((int) i, 255, 0);
index++;
}
for (float i=0; i<256; i += 256/42)
{
if (index == translatedHue)
return Color.rgb(255, 255-(int) i, 0);
index++;
}
return Color.RED;
}

// Update the main field colors depending on the current selected hue
private void updateMainColors()
{
int mainColor = getCurrentMainColor();
int index = 0;
int[] topColors = new int[256];
for (int y=0; y<256; y++)
{
for (int x=0; x<256; x++)
{
if (y == 0)
{
mMainColors[index] = Color.rgb(255-(255-Color.red(mainColor))*x/255, 255-(255-Color.green(mainColor))*x/255, 255-(255-Color.blue(mainColor))*x/255);
topColors[x] = mMainColors[index];
}
else
mMainColors[index] = Color.rgb((255-y)*Color.red(topColors[x])/255, (255-y)*Color.green(topColors[x])/255, (255-y)*Color.blue(topColors[x])/255);
index++;
}
}
}

@Override
protected void onDraw(Canvas canvas) {
int translatedHue = 255-(int)(mCurrentHue*255/360);
// Display all the colors of the hue bar with lines
for (int x=0; x<256; x++)
{
// If this is not the current selected hue, display the actual color
if (translatedHue != x)
{
mPaint.setColor(mHueBarColors[x]);
mPaint.setStrokeWidth(1);
}
else // else display a slightly larger black line
{
mPaint.setColor(Color.BLACK);
mPaint.setStrokeWidth(3);
}
canvas.drawLine(x+10, 0, x+10, 40, mPaint);
}

// Display the main field colors using LinearGradient
for (int x=0; x<256; x++)
{
int[] colors = new int[2];
colors[0] = mMainColors[x];
colors[1] = Color.BLACK;
Shader shader = new LinearGradient(0, 50, 0, 306, colors, null, Shader.TileMode.REPEAT);
mPaint.setShader(shader);
canvas.drawLine(x+10, 50, x+10, 306, mPaint);
}
mPaint.setShader(null);

// Display the circle around the currently selected color in the main field
if (mCurrentX != 0 && mCurrentY != 0)
{
mPaint.setStyle(Paint.Style.STROKE);
mPaint.setColor(Color.BLACK);
canvas.drawCircle(mCurrentX, mCurrentY, 10, mPaint);
}

// Draw a 'button' with the currently selected color
mPaint.setStyle(Paint.Style.FILL);
mPaint.setColor(mCurrentColor);
canvas.drawRect(10, 316, 138, 356, mPaint);

// Set the text color according to the brightness of the color
if (Color.red(mCurrentColor)+Color.green(mCurrentColor)+Color.blue(mCurrentColor) < 384)
mPaint.setColor(Color.WHITE);
else
mPaint.setColor(Color.BLACK);
//canvas.drawText(getResources().getString(R.string.hello), 74, 340, mPaint);

// Draw a 'button' with the default color
mPaint.setStyle(Paint.Style.FILL);
mPaint.setColor(mDefaultColor);
canvas.drawRect(138, 316, 266, 356, mPaint);

// Set the text color according to the brightness of the color
if (Color.red(mDefaultColor)+Color.green(mDefaultColor)+Color.blue(mDefaultColor) < 384)
mPaint.setColor(Color.WHITE);
else
mPaint.setColor(Color.BLACK);
   //canvas.drawText(getResources().getString(R.string.hello), 202, 340, mPaint);
}

@Override
protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
setMeasuredDimension(276, 366);
}
@Override
public boolean onTouchEvent(MotionEvent event) {
if (event.getAction() != MotionEvent.ACTION_DOWN) return true;
float x = event.getX();
float y = event.getY();

// If the touch event is located in the hue bar
if (x > 10 && x < 266 && y > 0 && y < 40)
{
// Update the main field colors
mCurrentHue = (255-x)*360/255;
updateMainColors();

// Update the current selected color
int transX = mCurrentX-10;
int transY = mCurrentY-60;
int index = 256*(transY-1)+transX;
if (index > 0 && index < mMainColors.length)
mCurrentColor = mMainColors[256*(transY-1)+transX];

// Force the redraw of the dialog
invalidate();
}
// If the touch event is located in the main field
if (x > 10 && x < 266 && y > 50 && y < 306)
{
mCurrentX = (int) x;
mCurrentY = (int) y;
int transX = mCurrentX-10;
int transY = mCurrentY-60;
int index = 256*(transY-1)+transX;
if (index > 0 && index < mMainColors.length)
{
// Update the current color
mCurrentColor = mMainColors[index];
// Force the redraw of the dialog
invalidate();
}
}
// If the touch event is located in the left button, notify the listener with the current color
if (x > 10 && x < 138 && y > 316 && y < 356)
mListener.colorChanged( mCurrentColor);

// If the touch event is located in the right button, notify the listener with the default color
if (x > 138 && x < 266 && y > 316 && y < 356)
mListener.colorChanged( mDefaultColor);

return true;
}
}

    public PickerDialog(Context context, OnColorChangedListener listener, int initialColor, int defaultColor) {
        super(context);

        mListener = listener;
      //  mKey = key;
        mInitialColor = initialColor;
        mDefaultColor = defaultColor;
    }
 
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
     
        OnColorChangedListener _ChangedListener = new OnColorChangedListener() {
            public void colorChanged( int color) {
                mListener.colorChanged(color);
                dismiss();
            }
        };

        setContentView(new ColorPickerView(getContext(), _ChangedListener, mInitialColor, mDefaultColor));
        setTitle("Color Picker");
    }
}

//Add this xml to  res/values 

4. COLOR.XML


<?xml version="1.0" encoding="utf-8"?>
<resources>
<color name="red">#ffff0000</color>
</resources>

1). we want choose any color use ing color picker  

Android Check Network Status

Android Check Network Status

public void CheckStatus() {  

 

ConnectivityManager connectionstate = (ConnectivityManager)               getSystemService(Context.CONNECTIVITY_SERVICE);

NetworkInfo network = connectionstate.getActiveNetworkInfo(); 

        

if (network != null && network.isConnected() == true) {

Toast.makeText(this, "Network Available", Toast.LENGTH_SHORT).show();

} else {

Toast.makeText(this, "Network Not Available", Toast.LENGTH_SHORT).show(); 

new AlertDialog.Builder(ChatsActivity.this)

            .setTitle("Connection failed")

            .setMessage("This application requires network access. Please, enable " + "mobile network or Wi-Fi.")

            

            .setPositiveButton("Accept", new DialogInterface.OnClickListener() {

            

                public void onClick(DialogInterface dialog, int which) {                         

                // Intent intent = new Intent(MainActivity.this, Settings.ACTION_WIRELESS_SETTINGS);

                // startActivity(intent);

                 ChatsActivity.this.startActivity(new Intent(Settings.ACTION_WIRELESS_SETTINGS));

                }

            })

            

            .setNegativeButton("Cancel", new DialogInterface.OnClickListener() {

                public void onClick(DialogInterface dialog, int which) {

                 ChatsActivity.this.finish();

                }

            })

            .show();  

}

}

and also add these permissions in manifest.xml

<uses-permission android:name="android.permission.ACCESS_NETWORK_STATE"/>