CheckBox

CheckBox

A CheckBox is an on/off switch that can be toggled by the user. You should use check-boxes when presenting users with a group of selectable options that are not mutually exclusive.

CHECKBOX

CheckBox Attributes

Following are the important attributes related to CheckBox control. You can check Android official documentation for complete list of attributes and related methods which you can use to change these attributes are run time.

Inherited from android.widget.TextView Class –

Sr.No	Attribute & Description
1	android:autoText If set, specifies that this TextView has a textual input method and automatically corrects some common spelling errors.
2	android:drawableBottom This is the drawable to be drawn below the text.
3	android:drawableRight This is the drawable to be drawn to the right of the text.
4	android:editable If set, specifies that this TextView has an input method.
5	android:text This is the Text to display.

Inherited from android.view.View Class −

Sr.No	Attribute & Description
1	android:background This is a drawable to use as the background.
2	android:contentDescription This defines text that briefly describes content of the view.
3	android:id This supplies an identifier name for this view.
4	android:onClick This is the name of the method in this View's context to invoke when the view is clicked.
5	android:visibility This controls the initial visibility of the view.

Example

This example will take you through simple steps to show how to create your own Android application using Linear Layout and CheckBox.

Step	Description
1	You will use Android Studio IDE to create an Android application and name it as myapplication under a package com.example.myapplication as explained in the Hello World Example chapter.
2	Modify src/MainActivity.java file to add a click event.
3	Modify the default content of res/layout/activity_main.xml file to include Android UI control.
4	No need to declare default string constants. Android studio takes care of default constants at string.xml
5	Run the application to launch Android emulator and verify the result of the changes done in the application.

Following is the content of the modified main activity file src/MainActivity.java. This file can include each of the fundamental lifecycle methods.

package com.example.myapplication;

import android.os.Bundle;

import android.app.Activity;

import android.widget.Button;

import android.view.View;

import android.view.View.OnClickListener;

import android.widget.CheckBox;

import android.widget.Toast;

public class MainActivity extends Activity {

   CheckBox ch1,ch2;

   Button b1,b2;

   @Override

   protected void onCreate(Bundle savedInstanceState) {

      super.onCreate(savedInstanceState);

      setContentView(R.layout.activity_main);

     

      ch1=(CheckBox)findViewById(R.id.checkBox1);

      ch2=(CheckBox)findViewById(R.id.checkBox2);

     

      b1=(Button)findViewById(R.id.button);

      b2=(Button)findViewById(R.id.button2);

      b2.setOnClickListener(new View.OnClickListener() {

        

         @Override

         public void onClick(View v) {

            finish();

         }

      });

      b1.setOnClickListener(new View.OnClickListener() {

        

         @Override

         public void onClick(View v) {

            StringBuffer result = new StringBuffer();

            result.append("Thanks : ").append(ch1.isChecked());

            result.append("\nThanks: ").append(ch2.isChecked());

            Toast.makeText(MainActivity.this, result.toString(),

               Toast.LENGTH_LONG).show();

         }

      });

   }

}

Following will be the content of res/layout/activity_main.xml file −

<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"

  

   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=".MainActivity">

  

   <TextView

      android:id="@+id/textView1"

      android:layout_width="wrap_content"

      android:layout_height="wrap_content"

      android:text="Example of checkbox"

      android:layout_alignParentTop="true"

      android:layout_centerHorizontal="true"

      android:textSize="30dp" />

     

   <CheckBox

      android:id="@+id/checkBox1"

      android:layout_width="wrap_content"

      android:layout_height="wrap_content"

      android:text="Do you like Tutorials Point"

      android:layout_above="@+id/button"

      android:layout_centerHorizontal="true" />

     

   <CheckBox

      android:id="@+id/checkBox2"

      android:layout_width="wrap_content"

      android:layout_height="wrap_content"

      android:text="Do you like android "

      android:checked="false"

      android:layout_above="@+id/checkBox1"

      android:layout_alignLeft="@+id/checkBox1"

      android:layout_alignStart="@+id/checkBox1" />

  

   <TextView

      android:id="@+id/textView2"

      android:layout_width="wrap_content"

      android:layout_height="wrap_content"

      android:layout_alignLeft="@+id/checkBox1"

      android:layout_below="@+id/textView1"

      android:layout_marginTop="39dp"

      android:text="Tutorials point"

      android:textColor="#ff87ff09"

      android:textSize="30dp"

      android:layout_alignRight="@+id/textView1"

      android:layout_alignEnd="@+id/textView1" />

     

   <Button

      android:layout_width="wrap_content"

      android:layout_height="wrap_content"

      android:text="Ok"

      android:id="@+id/button"

      android:layout_alignParentBottom="true"

      android:layout_alignLeft="@+id/checkBox1"

      android:layout_alignStart="@+id/checkBox1" />

     

   <Button

      android:layout_width="wrap_content"

      android:layout_height="wrap_content"

      android:text="Cancel"

      android:id="@+id/button2"

      android:layout_alignParentBottom="true"

      android:layout_alignRight="@+id/textView2"

      android:layout_alignEnd="@+id/textView2" />

     

   <ImageButton

      android:layout_width="wrap_content"

      android:layout_height="wrap_content"

      android:id="@+id/imageButton"

      android:src="@drawable/abc"

      android:layout_centerVertical="true"

      android:layout_centerHorizontal="true" />

     

</RelativeLayout>

Following will be the content of res/values/strings.xml to define these new constants −

<?xml version="1.0" encoding="utf-8"?>

<resources>

   <string name="app_name">MyApplication</string>  

</resources>

Following is the default content of AndroidManifest.xml −

<?xml version="1.0" encoding="utf-8"?>

<manifest xmlns:android="http://schemas.android.com/apk/res/android"

   package="com.example.myapplication" >

  

   <application

      android:allowBackup="true"

      android:icon="@drawable/ic_launcher"

      android:label="@string/app_name"

      android:theme="@style/AppTheme" >

     

      <activity

         android:name="com.example.myapplication.MainActivity"

         android:label="@string/app_name" >

     

         <intent-filter>

            <action android:name="android.intent.action.MAIN" />

            <category android:name="android.intent.category.LAUNCHER" />

         </intent-filter>

     

      </activity>

     

   </application>

</manifest>

Let's try to run your MyApplication application. I assume you had created your AVD while doing environment setup. To run the app from Android studio, open one of your project's activity files and click Run  icon from the toolbar. Android studio installs the app on your AVD and starts it and if everything is fine with your setup and application, it will display following Emulator window −