Kotlin Extensions of BottomNavigation, Calendar, EditText, View, InputStream, String, Context, Activity

ActivityExtensions.kt

import androidx.appcompat.app.AppCompatActivity
import androidx.lifecycle.ViewModel
import androidx.lifecycle.ViewModelProviders
import androidx.lifecycle.ViewModelProvider
import android.app.Activity
import android.content.Intent

inline fun <reified T : Any> Activity.openAndFinish(extras: Intent.() -> Unit = {}) {
    open<T>(extras)
    finish()
}

inline fun <reified T : Any> Activity.openForResult(requestCode: Int = 20, extras: Intent.() -> Unit = {}) {
    startActivityForResult(Intent(this, T::class.java).apply { extras() }, requestCode)
}

/**
* If you use ViewModel
*/
fun <T : ViewModel> AppCompatActivity.obtainViewModel(
    model: KClass<T>,
    viewModelFactory: ViewModelProvider.Factory? = null
) = ViewModelProviders.of(this, viewModelFactory).get(model.java)

BottomNavigationExtension.kt

import android.annotation.SuppressLint
import android.support.design.internal.BottomNavigationItemView
import android.support.design.internal.BottomNavigationMenuView
import android.support.design.widget.BottomNavigationView
import android.util.Log

/**
* Disable shifting mode on Bottom Navigation View
* 
* Source of the issue, 
* https://stackoverflow.com/questions/40176244/how-to-disable-bottomnavigationview-shift-mode
*/
@SuppressLint("RestrictedApi")
fun BottomNavigationView.disableShiftMode() {
    val menuView = this.getChildAt(0) as BottomNavigationMenuView

    try {
        val shiftingMode = menuView.javaClass.getDeclaredField("mShiftingMode")
        shiftingMode.isAccessible = true
        shiftingMode.setBoolean(menuView, false)
        shiftingMode.isAccessible = false

        for (i in 0 until menuView.childCount) {
            val item = menuView.getChildAt(i) as BottomNavigationItemView

            item.setShiftingMode(false)
            item.setChecked(item.itemData.isChecked)
        }
    } catch (e: NoSuchFieldException) {
        Log.e("BNVHelper", "Unable to get shift mode field", e)
    } catch (e: IllegalAccessException) {
        Log.e("BNVHelper", "Unable to change value of shift mode", e)
    }

}

CalendarExtension.kt

import java.text.SimpleDateFormat
import java.util.*

fun Calendar.format(outFormat: String): String {
    return SimpleDateFormat(outFormat, Locale.getDefault()).format(time)
}

ContextExtensions.kt

import android.app.Activity
import android.content.Context
import android.content.Intent
import android.os.Bundle
import android.widget.Toast
import androidx.core.app.ActivityCompat.startActivityForResult
import kotlin.reflect.KClass

fun Context.toast(text: String, duration: Int = Toast.LENGTH_SHORT) {
    Toast.makeText(this, text, duration).show()
}

inline fun <reified T : Any> Context.open(extras: Intent.() -> Unit = {}) {
    startActivity(Intent(this, T::class.java).apply { extras() })
}

inline fun <reified T : Any> Context.openAsNewTask(extras: Intent.() -> Unit = {}) {
    open<T> {
        addFlags(Intent.FLAG_ACTIVITY_CLEAR_TASK or Intent.FLAG_ACTIVITY_NEW_TASK)
        extras()
    }
}

fun <T : Any> Context.openForResult(
    activity: Activity,
    target: KClass<T>,
    requestCode: Int = 20,
    bundle: Bundle? = null,
    extras: Intent.() -> Unit = {}
) {
    startActivityForResult(
        activity,
        Intent(this, target.java).apply { extras() },
        requestCode,
        bundle
    )
}

EditTextExtension.kt

import android.widget.EditText

fun EditText.enable() {
    isEnabled = true
}

fun EditText.disable() {
    isEnabled = false
}

val EditText.value
    get() = text.toString()

InputStreamExtension.kt

import android.graphics.Bitmap
import android.graphics.BitmapFactory
import android.graphics.Matrix
import android.support.media.ExifInterface
import java.io.InputStream

/**
* Fix exif orientation of image taken from Camera or Gallery 
* on some devices
* 
* Source of the issue, 
* https://stackoverflow.com/questions/14066038/why-does-an-image-captured-using-camera-intent-gets-rotated-on-some-devices-on-a
*/
fun InputStream.getExifBitmap(filename: String? = null): Bitmap {
    val decodedBitmap = BitmapFactory.decodeStream(this)

    val exif = if (filename == null) ExifInterface(this) else ExifInterface(filename)
    val exifRotation = exif.getAttributeInt(ExifInterface.TAG_ORIENTATION, ExifInterface.ORIENTATION_NORMAL)

    val degreeRotation = when (exifRotation) {
        ExifInterface.ORIENTATION_ROTATE_90 -> 90
        ExifInterface.ORIENTATION_ROTATE_180 -> 180
        ExifInterface.ORIENTATION_ROTATE_270 -> 270
        else -> 0
    }

    val matrix = Matrix()
    if (exifRotation != 0) matrix.preRotate(degreeRotation.toFloat())

    return Bitmap.createBitmap(decodedBitmap, 0, 0, decodedBitmap.width, decodedBitmap.height, matrix, true)
}

StringExtension.kt

import java.text.SimpleDateFormat
import java.util.*

fun String.dateFormat(outFormat: String, inFormat: String = "yyyy-MM-dd HH:mm:ss"): String {
    return SimpleDateFormat(inFormat, Locale.getDefault()).run {
        val date = parse(this@dateFormat)
        applyPattern(outFormat)
        date?.let { format(it) }.orEmpty()
    }
}

fun String.isValidDateFormat(checkFormat: String): Boolean {
    return try {
        SimpleDateFormat(checkFormat, Locale.getDefault()).parse(this)
        true
    } catch (e: ParseException) {
        false
    }
}

ViewExtension.kt

import android.view.View

fun View.visible() {
    if (!isVisible) visibility = View.VISIBLE
}

fun View.gone() {
    if (!isGone) visibility = View.GONE
}

fun View.invisible() {
    if (!isInvisible) visibility = View.INVISIBLE
}

val View.isVisible
    get() = visibility == View.VISIBLE

val View.isInvisible
    get() = visibility == View.INVISIBLE

val View.isGone
    get() = visibility == View.GONE