Kotlin extension functions for creating AlertDialog in a DSL way

DialogExtensions.kt

import android.annotation.SuppressLint
import android.app.Activity
import android.app.AlertDialog
import android.content.Context
import android.support.annotation.StringRes
import android.support.v4.app.Fragment
import android.view.LayoutInflater
import android.view.View
import android.widget.Button
import android.widget.TextView
import com.eggdigital.trueyouedc.R

/**
 * Created by oakkub on 10/5/2017 AD.
 */

inline fun Activity.alert(title: CharSequence? = null, message: CharSequence? = null, func: AlertDialogHelper.() -> Unit): AlertDialog {
    return AlertDialogHelper(this, title, message).apply {
        func()
    }.create()
}

inline fun Activity.alert(titleResource: Int = 0, messageResource: Int = 0, func: AlertDialogHelper.() -> Unit): AlertDialog {
    val title = if (titleResource == 0) null else getString(titleResource)
    val message = if (messageResource == 0) null else getString(messageResource)
    return AlertDialogHelper(this, title, message).apply {
        func()
    }.create()
}

inline fun Fragment.alert(title: CharSequence? = null, message: CharSequence? = null, func: AlertDialogHelper.() -> Unit): AlertDialog {
    return AlertDialogHelper(context, title, message).apply {
        func()
    }.create()
}

inline fun Fragment.alert(titleResource: Int = 0, messageResource: Int = 0, func: AlertDialogHelper.() -> Unit): AlertDialog {
    val title = if (titleResource == 0) null else getString(titleResource)
    val message = if (messageResource == 0) null else getString(messageResource)
    return AlertDialogHelper(context, title, message).apply {
        func()
    }.create()
}

@SuppressLint("InflateParams")
class AlertDialogHelper(context: Context, title: CharSequence?, message: CharSequence?) {

    private val dialogView: View by lazyFast {
        LayoutInflater.from(context).inflate(R.layout.dialog_info, null)
    }

    private val builder: AlertDialog.Builder = AlertDialog.Builder(context)
            .setView(dialogView)

    private val title: TextView by lazyFast {
        dialogView.findViewById<TextView>(R.id.dialogInfoTitleTextView)
    }

    private val message: TextView by lazyFast {
        dialogView.findViewById<TextView>(R.id.dialogInfoMessageTextView)
    }

    private val positiveButton: Button by lazyFast {
        dialogView.findViewById<Button>(R.id.dialogInfoPositiveButton)
    }

    private val negativeButton: Button by lazyFast {
        dialogView.findViewById<Button>(R.id.dialogInfoNegativeButton)
    }

    private var dialog: AlertDialog? = null

    var cancelable: Boolean = true

    init {
        this.title.text = title
        this.message.text = message
    }

    fun positiveButton(@StringRes textResource: Int, func: (() -> Unit)? = null) {
        with(positiveButton) {
            text = builder.context.getString(textResource)
            setClickListenerToDialogButton(func)
        }
    }

    fun positiveButton(text: CharSequence, func: (() -> Unit)? = null) {
        with(positiveButton) {
            this.text = text
            setClickListenerToDialogButton(func)
        }
    }

    fun negativeButton(@StringRes textResource: Int, func: (() -> Unit)? = null) {
        with(negativeButton) {
            text = builder.context.getString(textResource)
            setClickListenerToDialogButton(func)
        }
    }

    fun negativeButton(text: CharSequence, func: (() -> Unit)? = null) {
        with(negativeButton) {
            this.text = text
            setClickListenerToDialogButton(func)
        }
    }

    fun onCancel(func: () -> Unit) {
        builder.setOnCancelListener { func() }
    }

    fun create(): AlertDialog {
        title.goneIfTextEmpty()
        message.goneIfTextEmpty()
        positiveButton.goneIfTextEmpty()
        negativeButton.goneIfTextEmpty()

        dialog = builder
                .setCancelable(cancelable)
                .create()
        return dialog!!
    }

    private fun TextView.goneIfTextEmpty() {
        visibility = if (text.isNullOrEmpty()) {
            View.GONE
        } else {
            View.VISIBLE
        }
    }

    private fun Button.setClickListenerToDialogButton(func: (() -> Unit)?) {
        setOnClickListener {
            func?.invoke()
            dialog?.dismiss()
        }
    }

}

you can use inline fun Context.alert()... instade of Activity or Fragment. Good job!..

If you add How can we use this in Fragment to or activity that would be helpful.

can be used by this way

alert("I AM TITLE", "I AM MESSAGE") {
      positiveButton("Ok") {
      }
      negativeButton("Cancel"){
      }
  }.show()

Thanks @rakesh-anvd

Thanks, it helped me. Regards, Shailendra.

…

On Wed, Jul 15, 2020 at 9:42 PM rakeshr-anvd ***@***.***> wrote: ***@***.**** commented on this gist. ------------------------------ can we used by this way alert("I AM TITLE", "I AM MESSAGE") { positiveButton("Ok") { } negativeButton("Cancel"){ } }.show() — You are receiving this because you commented. Reply to this email directly, view it on GitHub <https://gist.github.com/887522d1c0dff980a3b63bb5f30a1dbe#gistcomment-3378153>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/AA2UQVPP7LWKFLFU3CG6YI3R3XIP7ANCNFSM4KGVFXOQ> .

@shylendramadda

The above util extension can be simplified by using context instead of

Activity.alert(){}
Fragment.alert(){}

with

Context.alert(){}

Yeah got it, thanks Regards, Shailendra.

…

On Thu, Jul 16, 2020 at 3:31 PM rakeshr-anvd ***@***.***> wrote: ***@***.**** commented on this gist. ------------------------------ @shylendramadda <https://github.com/shylendramadda> The above util extension can be simplified by using context instead of Activity.alert(){} Fragment.alert(){} with Context.alert(){} — You are receiving this because you were mentioned. Reply to this email directly, view it on GitHub <https://gist.github.com/887522d1c0dff980a3b63bb5f30a1dbe#gistcomment-3379407>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/AA2UQVJXTVG6L2AUCBZ34A3R33FV3ANCNFSM4KGVFXOQ> .