Extension methods written in Kotlin useful in daily Android development

Extensions.kt

@file:JvmName("ExtensionsUtils")

package com.example.piotr.kotlin_project.commons.extension

import android.text.TextUtils
import android.view.LayoutInflater
import android.view.View
import android.view.ViewGroup
import android.widget.ImageView
import com.example.piotr.kotlin_project.R
import com.squareup.picasso.Picasso

/**
 * @author piotr on 29.07.16.
 */

/**
 * Check: http://antonioleiva.com/kotlin-awesome-tricks-for-android/
 * For API examples: http://antonioleiva.com/api-request-kotlin/
 */

fun ViewGroup.inflate(@LayoutRes layoutRes: Int, attachToRoot: Boolean = false) : View {
return LayoutInflater.from(context).inflate(layoutRes, this, attachToRoot)
}

fun ImageView.loadImg(imageUrl: String) {
    if (TextUtils.isEmpty(imageUrl)) {
        Picasso.with(context).load(R.mipmap.ic_launcher).into(this)
    } else {
        Picasso.with(context).load(imageUrl).into(this)
    }
}

fun Activity.toast(message: CharSequence, duration: Int = Toast.LENGTH_SHORT) {

    Toast.makeText(this, message, duration)
.show()
}

inline fun View.snack(message: String, length: Int = Snackbar.LENGTH_LONG, f: Snackbar.() -> Unit) {
    val snack = Snackbar.make(this, message, length)
    snack.f()
    snack.show()
}

fun Snackbar.action(action: String, color: Int? = null, listener: (View) -> Unit) {
    setAction(action, listener)
    color?.let { setActionTextColor(color) }
}

/*
The find function belongs to Anko library. But you can do something similar quite easy:
*/
inline fun <reified T : View> Activity.find(id: Int): T = findViewById(id) as T

//create an extension property that returns a list of the views:
val ViewGroup.views: List<View>
    get() = (0 until childCount).map { getChildAt(it) }
    
//use as navigate<DetailActivity>("2")
inline fun <reified T : Activity> Activity.navigate(id: String) {
    val intent = Intent(this, T::class.java)
    intent.putExtra("id", id)
    startActivity(intent)
}

SquareImageView.kt

class SquareImageView : ImageView {
 
    constructor(context: Context) : super(context)
 
    constructor(context: Context, attrs: AttributeSet) : super(context, attrs)
 
    constructor(context: Context, attrs: AttributeSet, defStyleAttr: Int) : super(context, attrs, defStyleAttr)
 
    override fun onMeasure(widthMeasureSpec: Int, heightMeasureSpec: Int) {
        super.onMeasure(widthMeasureSpec, heightMeasureSpec)
        val width = getMeasuredWidth()
        setMeasuredDimension(width, width)
    }
}