Android code snippets in Kotlin

AndroidSnippets.kt

// Make EditText clickable not editable
fun makeEditTextClickable(et:EditText){
    et.isFocusableInTouchMode = false
    et.isLongClickable = false
}

// extract activity from a given context
fun requireActivity(context: Context): Activity {
    if (context is Activity) {
        return context
    } else if (context is ContextWrapper) {
        return requireActivity(context.baseContext)
    }
    throw IllegalArgumentException("Unable to extract activity from $context")
}

// get uri from a resource id
fun resourceToUri(context: Context, resID: Int): Uri {
    return Uri.parse(
        ContentResolver.SCHEME_ANDROID_RESOURCE + "://" +
                context.resources.getResourcePackageName(resID) + '/' +
                context.resources.getResourceTypeName(resID) + '/' +
                context.resources.getResourceEntryName(resID)
    )
}

// hide keyboard in an activity if present
fun hideKeyboard(activity: Activity) {
    hideKeyboard(activity.currentFocus)
}
fun hideKeyboard(view: View?, rr: ResultReceiver? = null) {
    if (view != null) {
        view.clearFocus()
        val imm =
            view.context.getSystemService(Context.INPUT_METHOD_SERVICE) as InputMethodManager
        imm.hideSoftInputFromWindow(view.windowToken, 0, rr)
        imm.hideSoftInputFromInputMethod(view.windowToken, 0)
    }
}

// show keyboard for this view
fun showKeyboard(on: View) {
    val inputMethodManager = on.context.getSystemService(Context.INPUT_METHOD_SERVICE) as InputMethodManager
    on.requestFocus()
    inputMethodManager.toggleSoftInputFromWindow(
        on.applicationWindowToken,
        InputMethodManager.SHOW_IMPLICIT, 0
    )
    // inputMethodManager.showSoftInput(on, InputMethodManager.SHOW_FORCED);
}

// make view and all children enabled or disabled
fun setEnabledRecursive(view:View, enabled: Boolean){
    view.isEnabled = enabled
    if(view is ViewGroup){
        for (child in view.children) {
            setEnabledRecursive(child, enabled)
        }
    }
}

// retreives the unique device id
fun deviceId(context: Context): String {
    return Settings.Secure.getString(
        context.contentResolver,
        Settings.Secure.ANDROID_ID
    )
}

// calculate the sample size
fun calculateInSampleSize(options: BitmapFactory.Options, reqWidth: Int, reqHeight: Int): Int {
    // Raw height and width of image
    val (height: Int, width: Int) = options.run { outHeight to outWidth }
    var inSampleSize = 1

    if (height > reqHeight || width > reqWidth) {

        val halfHeight: Int = height / 2
        val halfWidth: Int = width / 2

        // Calculate the largest inSampleSize value that is a power of 2 and keeps both
        // height and width larger than the requested height and width.
        while (halfHeight / inSampleSize >= reqHeight && halfWidth / inSampleSize >= reqWidth) {
            inSampleSize *= 2
        }
    }

    return inSampleSize
}

// get small bitmap from resource
// low memory usage
fun decodeSampledBitmapFromResource(
        res: Resources,
        resId: Int,
        reqWidth: Int,
        reqHeight: Int
    ): Bitmap {
    // First decode with inJustDecodeBounds=true to check dimensions
    return BitmapFactory.Options().run {
        inJustDecodeBounds = true
        BitmapFactory.decodeResource(res, resId, this)

        // Calculate inSampleSize
        inSampleSize = calculateInSampleSize(this, reqWidth, reqHeight)

        // Decode bitmap with inSampleSize set
        inJustDecodeBounds = false

        BitmapFactory.decodeResource(res, resId, this)
    }
}

// get small bitmap from file
// low memory usage
fun decodeSampledBitmapFromFile(
    file: File,
    reqWidth: Int,
    reqHeight: Int
): Bitmap {
    // First decode with inJustDecodeBounds=true to check dimensions
    return BitmapFactory.Options().run {
        inJustDecodeBounds = true
        BitmapFactory.decodeFile(file.absolutePath, this)

        // Calculate inSampleSize
        inSampleSize = calculateInSampleSize(this, reqWidth, reqHeight)

        // Decode bitmap with inSampleSize set
        inJustDecodeBounds = false

        BitmapFactory.decodeFile(file.absolutePath, this)
    }
}

// return the md5 of the string
fun md5(what: String): String {
    val MD5 = "MD5"
    try {
        // Create MD5 Hash
        val digest: java.security.MessageDigest = java.security.MessageDigest.getInstance(MD5)
        digest.update(what.toByteArray())
        val messageDigest: ByteArray = digest.digest()

        // Create Hex String
        val hexString: java.lang.StringBuilder = java.lang.StringBuilder()
        for (aMessageDigest in messageDigest) {
            var h: String = java.lang.Integer.toHexString(0xFF and aMessageDigest.toInt())
            while (h.length < 2) h = "0$h"
            hexString.append(h)
        }
        return hexString.toString()
    } catch (e: java.security.NoSuchAlgorithmException) {
        e.printStackTrace()
    }
    return ""
}

// get distance between two Points
fun getDistance(from: Point, to: Point): Double {
    return Math.sqrt(
        Math.pow(from.x - to.x.toDouble(), 2.0) +
                Math.pow(from.y - to.y.toDouble(), 2.0)
    )
}

// get distance between two PointFs
fun getDistance(from: PointF, to: PointF): Double {
    return Math.sqrt(
        Math.pow(from.x - to.x.toDouble(), 2.0) +
                Math.pow(from.y - to.y.toDouble(), 2.0)
    )
}

// get angle from src to target Points
fun getAngle(src: Point, target: Point): Float {
    var angle = Math.toDegrees(
        Math.atan2(
            target.y - src.y.toDouble(),
            target.x - src.x.toDouble()
        )
    ).toFloat()
    if (angle < 0) {
        angle += 360f
    }
    return angle
}

// get angle from src to target PointFs
fun getAngle(src: PointF, target: PointF): Float {
    var angle = Math.toDegrees(
        Math.atan2(
            target.y - src.y.toDouble(),
            target.x - src.x.toDouble()
        )
    ).toFloat()
    if (angle < 0) {
        angle += 360f
    }
    return angle
}

// if @value smaller than the @min then return @min
// else if @value bigger than @max then return @max
// else return @value it self
fun minOrMax(value: Float, min: Float, max: Float): Float {
    if (value < min) return min
    return if (value > max) max else value
}

// check if @v is divisible by @d
fun isDivisible(v: Float, d: Float): Boolean {
    return v % d == 0f
}

// check if @v is divisible by @d
fun isDivisible(v: Int, d: Int): Boolean {
    return v % d == 0
}

// evaluate color from color @startInt to color @endIt in @fraction
// fraction is between 0-1
fun evaluateColor(fraction: Float, startInt: Int, endInt: Int): Int {
    val startA = (startInt shr 24 and 0xff) / 255.0f
    var startR = (startInt shr 16 and 0xff) / 255.0f
    var startG = (startInt shr 8 and 0xff) / 255.0f
    var startB = (startInt and 0xff) / 255.0f
    val endA = (endInt shr 24 and 0xff) / 255.0f
    var endR = (endInt shr 16 and 0xff) / 255.0f
    var endG = (endInt shr 8 and 0xff) / 255.0f
    var endB = (endInt and 0xff) / 255.0f
    // convert from sRGB to linear
    startR = Math.pow(startR.toDouble(), 2.2).toFloat()
    startG = Math.pow(startG.toDouble(), 2.2).toFloat()
    startB = Math.pow(startB.toDouble(), 2.2).toFloat()
    endR = Math.pow(endR.toDouble(), 2.2).toFloat()
    endG = Math.pow(endG.toDouble(), 2.2).toFloat()
    endB = Math.pow(endB.toDouble(), 2.2).toFloat()
    // compute the interpolated color in linear space
    var a = startA + fraction * (endA - startA)
    var r = startR + fraction * (endR - startR)
    var g = startG + fraction * (endG - startG)
    var b = startB + fraction * (endB - startB)
    // convert back to sRGB in the [0..255] range
    a = a * 255.0f
    r = Math.pow(r.toDouble(), 1.0 / 2.2).toFloat() * 255.0f
    g = Math.pow(g.toDouble(), 1.0 / 2.2).toFloat() * 255.0f
    b = Math.pow(b.toDouble(), 1.0 / 2.2).toFloat() * 255.0f
    return Math.round(a) shl 24 or (Math.round(r) shl 16) or (Math.round(
        g
    ) shl 8) or Math.round(b)
}

// convert persian numbers to latin numbers in @text
fun persianNumbersToEnglishNumbers(text: String): String {
    return text
            .replace("۰", "0")
            .replace("۱", "1")
            .replace("۲", "2")
            .replace("۳", "3")
            .replace("۴", "4")
            .replace("۵", "5")
            .replace("۶", "6")
            .replace("۷", "7")
            .replace("۸", "8")
            .replace("۹", "9")
}
// convert latin numbers to persian numbers in @text
fun englishNumbersToPersianNumbers(text: String): String {
    return text
            .replace("0", "۰")
            .replace("1", "۱")
            .replace("2", "۲")
            .replace("3", "۳")
            .replace("4", "۴")
            .replace("5", "۵")
            .replace("6", "۶")
            .replace("7", "۷")
            .replace("8", "۸")
            .replace("9", "۹")
}

// convert long to readable byte in Binary
// Binary (1 K = 1,024)
fun humanReadableByteCountBin(bytes: Long): String {
    val b = if (bytes == Long.MIN_VALUE) Long.MAX_VALUE else java.lang.Math.abs(bytes)
    return if (b < 1024L) "$bytes B" else if (b <= 0xfffccccccccccccL shr 40) String.format("%.1f KiB", bytes / 0x1 p10 .0) else if (b <= 0xfffccccccccccccL shr 30) String.format("%.1f MiB", bytes / 0x1 p20 .0) else if (b <= 0xfffccccccccccccL shr 20) String.format("%.1f GiB", bytes / 0x1 p30 .0) else if (b <= 0xfffccccccccccccL shr 10) String.format("%.1f TiB", bytes / 0x1 p40 .0) else if (b <= 0xfffccccccccccccL) String.format("%.1f PiB", (bytes shr 10) / 0x1 p40 .0) else String.format("%.1f EiB", (bytes shr 20) / 0x1 p40 .0)
}

// convert long to readable byte
// SI (1 k = 1,000)
fun humanReadableByteCountSI(bytes: Long): String {
    val s = if (bytes < 0) "-" else ""
    var b = if (bytes == Long.MIN_VALUE) Long.MAX_VALUE else java.lang.Math.abs(bytes)
    return if (b < 1000L) "$bytes B" else if (b < 999950L) String.format("%s%.1f kB", s, b / 1e3) else if (1000.let { b /= it; b } < 999950L) String.format("%s%.1f MB", s, b / 1e3) else if (1000.let { b /= it; b } < 999950L) String.format("%s%.1f GB", s, b / 1e3) else if (1000.let { b /= it; b } < 999950L) String.format("%s%.1f TB", s, b / 1e3) else if (1000.let { b /= it; b } < 999950L) String.format("%s%.1f PB", s, b / 1e3) else String.format("%s%.1f EB", s, b / 1e6)
}