Creating CheckBox in Android

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Checkbox:-  

Check boxes are used when you want to use want to select one or more option from a set of alternative if only one option is to be selected at a time then you must select RadioButton

Select the Item in Checkbox :- 

In this example. There four checkbox Tea,Snecks,Coffee,Pakodas
Whatever you choose the checkbox value is show in TextView.

Layout of program:-

Layout of Checkbox

 We make it by Graphical Method:By default in Graphical Method it show Icon and Text in pop down menu.We can can select Show only Icon.

Graphical Design of Checkbox problem

Graphical and Properties view

 When you select the view in Graphical its prproperties is shown in Right Pan of eclipse. if it is not show you can Window->show View->properties. you can choose the value of properties.

By drag and drop you make easily layout once you make the main.xml file auto generated
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    android:orientation="vertical" >

    <TextView
        android:id="@+id/checkboxid"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="@string/example"
        android:textColor="@color/green"
        android:textSize="32dp" />

    <CheckBox
        android:id="@+id/teaid"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="@string/t"
        android:textColor="@color/col2" />

    <CheckBox
        android:id="@+id/sneckid"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="@string/s"
        android:textColor="@color/col3" />

    <CheckBox
        android:id="@+id/coffeeid"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="@string/c"
        android:textColor="@color/col4" />

    <CheckBox
        android:id="@+id/pakodasid"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="@string/p"
        android:textColor="@color/col5" />
    <TextView
        android:id="@+id/textView1"
        android:layout_width="112dp"
        android:layout_height="wrap_content"
        android:layout_gravity="center"
        android:textSize="16dp"
        android:text="@string/distxt" />
</LinearLayout>

String.xml

Android Resources(default)

Explanation:

Here is 

Hello and app_name is default String

Four checkbox label

Five  color label

One Label Example String

One TextView

 
















  Now the Java Source Code

Java Source Code:-


package abh.checkbutton.com;


import android.app.Activity;
import android.os.Bundle;
import android.widget.*;

public class CheckbuttonexampleActivity extends Activity implements CompoundButton.OnCheckedChangeListener  {
    /** Called when the activity is first created. */
    CheckBox  te,sn,cof,pak;
    TextView tv;
  
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
      
      
        setContentView(R.layout.main);
        te=(CheckBox) findViewById(R.id.teaid);
        sn=(CheckBox) findViewById(R.id.sneckid);
        cof=(CheckBox) findViewById(R.id.coffeeid);
        pak=(CheckBox) findViewById(R.id.pakodasid);
        tv=(TextView) findViewById(R.id.textView1);
        te.setOnCheckedChangeListener(this);
        sn.setOnCheckedChangeListener(this);
        cof.setOnCheckedChangeListener(this);
        pak.setOnCheckedChangeListener(this);
      
    }

    public void onCheckedChanged(CompoundButton buttonView, boolean isChecked) {
        String str=" ";
        if(te.isChecked())
        {
            str=str+te.getText();
            tv.setText(str);
          
        }
        if(sn.isChecked())
        {
            str=str+","+sn.getText();
            tv.setText(str);
        }
        if(cof.isChecked())
        {
            str=str+","+cof.getText();
            tv.setText(str);
        }
        if(pak.isChecked())
        {
            str=str+","+pak.getText();
            tv.setText(str);
        }
    }
  

}

Expanation:- 
We define  OnCheckedChangeListener but we need to wire it to UI element before it come to action.There is two line of code that connect to checkbox to listen the checkbox click event
(1) Declaration of checkbox in main.xml file
 

  <CheckBox
        android:id="@+id/teaid"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="@string/t"
        android:textColor="@color/col2" />

    <CheckBox
        android:id="@+id/sneckid"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="@string/s"
        android:textColor="@color/col3" />

    <CheckBox
        android:id="@+id/coffeeid"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="@string/c"
        android:textColor="@color/col4" />

    <CheckBox
        android:id="@+id/pakodasid"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="@string/p"
        android:textColor="@color/col5" />   

(2)  te,sn,cof,pak,tv,te,te,sn,cof,pak is checkbox variable is connected to setOnCheckedChangeListener(this) by two line of code for each checkbox

        te=(CheckBox) findViewById(R.id.teaid);
        sn=(CheckBox) findViewById(R.id.sneckid);
        cof=(CheckBox) findViewById(R.id.coffeeid);
        pak=(CheckBox) findViewById(R.id.pakodasid);
        tv=(TextView) findViewById(R.id.textView1); 

        te.setOnCheckedChangeListener(this);
        sn.setOnCheckedChangeListener(this);
        cof.setOnCheckedChangeListener(this);
        pak.setOnCheckedChangeListener(this);

public void onCheckedChanged(CompoundButton buttonView, boolean isChecked)

 It is method which takes two parameter CompoundButton and boolean.  checkedId is Id of the checkbox which is clicked.

tv.setText(str):-By this method you can set the value of checkbox in TextView.