Android Tutorial 19 : Adding Check Boxes In Alert Dialog

We can also add check boxes in Alert Dialog and we can check multiple, it is used when we want mutiple option to be selected.

Handling the Click Events on CheckBoxes:

when a Checkbox is clocked means it is checked or unchecked obClick() method is called and the index of the selected item is passed, we can use this index to get the item which is checked

Create an Object of AlertDialog

AlertDialog dialog; 

//following code will be in your activity.java file 

final CharSequence[] items = {" Easy "," Medium "," Hard "," Very Hard "};
                // arraylist to keep the selected items
                final ArrayList seletedItems=new ArrayList();
              
                AlertDialog.Builder builder = new AlertDialog.Builder(this);
                builder.setTitle("Select The Difficulty Level");
                builder.setMultiChoiceItems(items, null,
                        new DialogInterface.OnMultiChoiceClickListener() {
                 // indexSelected contains the index of item (of which checkbox checked)
                 @Override
                 public void onClick(DialogInterface dialog, int indexSelected,
                         boolean isChecked) {
                     if (isChecked) {
                         // If the user checked the item, add it to the selected items
                         // write your code when user checked the checkbox 
                         seletedItems.add(indexSelected);
                     } else if (seletedItems.contains(indexSelected)) {
                         // Else, if the item is already in the array, remove it 
                         // write your code when user Uchecked the checkbox 
                         seletedItems.remove(Integer.valueOf(indexSelected));
                     }
                 }
             })
              // Set the action buttons
             .setPositiveButton("OK", new DialogInterface.OnClickListener() {
                 @Override
                 public void onClick(DialogInterface dialog, int id) {
                     //  Your code when user clicked on OK
                     //  You can write the code  to save the selected item here
                   
                 }
             })
             .setNegativeButton("Cancel", new DialogInterface.OnClickListener() {
                 @Override
                 public void onClick(DialogInterface dialog, int id) {
                    //  Your code when user clicked on Cancel
                  
                 }
             });
      
                dialog = builder.create();//AlertDialog dialog; create like this outside onClick
                dialog.show();
        }