MainActivity.kt
package com.example.jetpack
import android.content.Context
import android.os.Bundle
import android.util.DisplayMetrics
import androidx.appcompat.app.AppCompatActivity
import kotlinx.android.synthetic.main.activity_main.*
import kotlin.random.Random
class MainActivity : AppCompatActivity() {
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
setContentView(R.layout.activity_main)
// generate a random integer number in range
val pixels = Random.nextInt(50,200)
// convert pixels to equivalent dp value
val dp = pixels.pixelsToDp(this)
val dpInt = pixels.pixelsToDpInt(this)
// show pixels to dp actual float value
textView.text = "Return float value"
textView.append("\n$pixels pixels = $dp dp")
// pixels to dp integer conversion result
textView.append("\n\nReturn integer value")
textView.append("\n$pixels pixels = $dpInt dp")
}
}
// extension function to convert pixels to dp
// this method return dp perfect float value
fun Int.pixelsToDp(context: Context):Float{
return this / (context.resources
.displayMetrics.densityDpi / DisplayMetrics.DENSITY_DEFAULT).toFloat()
}
// extension function to convert pixels value to dp value
// this method return integer dp value
fun Int.pixelsToDpInt(context: Context):Int{
return this / (context.resources
.displayMetrics.densityDpi / DisplayMetrics.DENSITY_DEFAULT)
}
activity_main.xml
<?xml version="1.0" encoding="utf-8"?>
<androidx.constraintlayout.widget.ConstraintLayout
xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:id="@+id/constraintLayout"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context=".MainActivity"
android:background="#E5E4E2">
<TextView
android:id="@+id/textView"
android:layout_width="0dp"
android:layout_height="wrap_content"
android:layout_marginStart="16dp"
android:layout_marginTop="32dp"
android:layout_marginEnd="16dp"
tools:text="TextView"
android:fontFamily="sans-serif-condensed"
android:textSize="30sp"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="parent" />
</androidx.constraintlayout.widget.ConstraintLayout>

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