How to do Alert dialog in Android Kotlin return boolean value

Question

I want to make static function with Alert dialog which return boolean value.

In C# it looks like:

DialogResult dialogResult = MessageBox.Show("Sure", "Some Title", MessageBoxButtons.YesNo);
if(dialogResult == DialogResult.Yes)
{
    //do something
}
else if (dialogResult == DialogResult.No)
{
    //do something else
}

In Kotlin i have class with companion object

class Dialog {
    companion object {
        fun question(context: Context, title: String, message: String) {
            AlertDialog.Builder(context).apply {
                setIcon(R.drawable.ic_question)
                setTitle(title)
                setMessage(message)
                setPositiveButton("YES", DialogInterface.OnClickListener { dialog, which ->
                })
                setNegativeButton("NO", DialogInterface.OnClickListener { dialog, which ->
                })
            }.show()

        }
    }
}
        

And i want to return Boolean result from question function.

I want to use this function in my activity like this:

if(Dialog.question(this,"Title", "Message")) {
    //something
} else {
    //something
}

Is it possible?

Answer 1

Yes it is possible.

What you need:

• Extend your Dialog.kt class with DialogFragment()
• Create an interface for your activity in the dialog class
• Define a function which is called when the dialog closes
• Override the dialog interface to make what you need
• Use your interface

This is the implementation in my code (tested and working)

---

Implementation:

Extend your Dialog.kt class with DialogFragment, adapt your code to this and create the interface

class Dialog: DialogFragment() {
    interface InputListener {
        fun sendBoolean(value: Boolean)
    }
    ...
}

In the positive / negative listeners lambdas, init your interface and send the boolean

val inputListener = activity as InputListener
inputListener.sendInput(YOUR_VALUE)
dialog?.dismiss()

Go to your activity and extend it with your interface

class MainActivity: AppCompatActivity(), Dialog.InputListener {
   ...
}

And now finally, override the interface in the activity to run the code you need

override fun sendInput(value: Boolean) {
    if (value) {
        // Positive - true
    } else {
        // Negative - false
    }
}

Please let me know if this solved your problem, if not, try updating your question with what's wrong and I'll help you by updating my answer, happy coding!