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Android Widget – CheckBox

In Android, you can use “android.widget.CheckBox” class to render a checkbox.

In this tutorial, we show you how to create 3 checkboxes in XML file, and demonstrates the use of listener to check the checkbox state – checked or unchecked.

Open “your.xml” file, just add add 3 “CheckBox” and a button, inside the LinearLayout.

<!--?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">
    <checkbox android:id="@+id/chkIos" android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="@string/chk_ios">
        
    <checkbox android:id="@+id/chkAndroid" android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="@string/chk_android" android:checked="true">
    <checkbox android:id="@+id/chkWindows" android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="@string/chk_windows">
    <button android:id="@+id/btnDisplay" android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="@string/btn_display">
//Put android:checked="true" inside checkbox element to make it checked bu default.
// In this case, "Android" option is checked by default.</button></checkbox></checkbox></checkbox></linearlayout>

Attach listeners inside your activity “onCreate()” method, to monitor following events :
If checkbox id : “chkIos” is checked, display a floating box with message “Bro, try Android”.
If button is is clicked, display a floating box and display the checkbox states.

public class MainActivity extends Activity {
  private CheckBox chkIos, chkAndroid, chkWindows;
  private Button btnDisplay;
  @Override
  public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.main);
    addListenerOnChkIos();
    addListenerOnButton();
  }
  public void addListenerOnChkIos() {
    chkIos = (CheckBox) findViewById(R.id.chkIos);
    chkIos.setOnClickListener(new OnClickListener() {
      @Override
      public void onClick(View v) {
                //is chkIos checked?
        if (((CheckBox) v).isChecked()) {
            Toast.makeText(MyAndroidAppActivity.this,
               "Bro, try Android :)", Toast.LENGTH_LONG).show();
        }
      }
    });
  }
  public void addListenerOnButton() {
    chkIos = (CheckBox) findViewById(R.id.chkIos);
    chkAndroid = (CheckBox) findViewById(R.id.chkAndroid);
    chkWindows = (CheckBox) findViewById(R.id.chkWindows);
    btnDisplay = (Button) findViewById(R.id.btnDisplay);
    btnDisplay.setOnClickListener(new OnClickListener() {
          //Run when button is clicked
      @Override
      public void onClick(View v) {
        StringBuffer result = new StringBuffer();
        result.append("IPhone check : ").append(chkIos.isChecked());
        result.append("\nAndroid check : ").append(chkAndroid.isChecked());
        result.append("\nWindows Mobile check :").append(chkWindows.isChecked());
        Toast.makeText(MyAndroidAppActivity.this, result.toString(),
                Toast.LENGTH_LONG).show();
      }
    });
  }
}