MainActivity.kt
package com.example.jetpack
import android.content.Context
import android.graphics.*
import android.os.Bundle
import androidx.appcompat.app.AppCompatActivity
import kotlinx.android.synthetic.main.activity_main.*
import java.io.IOException
import kotlin.math.min
class MainActivity : AppCompatActivity() {
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
setContentView(R.layout.activity_main)
// get bitmap from assets folder
val bitmap: Bitmap? = assetsToBitmap("flower9.jpg")
// show bitmap on first image view
bitmap?.apply { imageView.setImageBitmap(this) }
// crop specified size circular area from bitmap
bitmap?.cropCircularArea(700)?.apply {
imageView2.setImageBitmap(this)
textView.text = "Circular image view, crop radius: 350 pixels"
}
}
}
// extension function to crop specified size circular area from bitmap
fun Bitmap.cropCircularArea(
diameter:Int = min(width,height)
):Bitmap?{
val bitmap = Bitmap.createBitmap(
width, // width in pixels
height, // height in pixels
Bitmap.Config.ARGB_8888
)
val canvas = Canvas(bitmap)
// create a circular path
val path = Path()
val length = min(diameter,min(width,height))
val radius = length / 2F // in pixels
path.apply {
addCircle(
width/2f,
height/2f,
radius,
Path.Direction.CCW
)
}
// draw circular bitmap on canvas
canvas.clipPath(path)
canvas.drawBitmap(this,0f,0f,null)
val x = (width - length)/2
val y = (height - length)/2
// return cropped circular bitmap
return Bitmap.createBitmap(
bitmap, // source bitmap
x, // x coordinate of the first pixel in source
y, // y coordinate of the first pixel in source
length, // width
length // height
)
}
// extension function to get bitmap from assets
fun Context.assetsToBitmap(fileName: String): Bitmap?{
return try {
with(assets.open(fileName)){
BitmapFactory.decodeStream(this)
}
} catch (e: IOException) { null }
}
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"
android:background="#DCDCDC"
tools:context=".MainActivity">
<ImageView
android:id="@+id/imageView"
android:layout_width="0dp"
android:layout_height="260dp"
android:layout_marginStart="8dp"
android:layout_marginTop="8dp"
android:layout_marginEnd="8dp"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="parent"
tools:srcCompat="@tools:sample/avatars" />
<ImageView
android:id="@+id/imageView2"
android:layout_width="0dp"
android:layout_height="260dp"
android:layout_marginStart="8dp"
android:layout_marginTop="16dp"
android:layout_marginEnd="8dp"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toBottomOf="@+id/imageView"
tools:srcCompat="@tools:sample/avatars" />
<TextView
android:id="@+id/textView"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginTop="8dp"
tools:text="TextView"
android:fontFamily="sans-serif-condensed-medium"
style="@style/TextAppearance.AppCompat.Medium"
app:layout_constraintEnd_toEndOf="@+id/imageView2"
app:layout_constraintStart_toStartOf="@+id/imageView2"
app:layout_constraintTop_toBottomOf="@+id/imageView2" />
</androidx.constraintlayout.widget.ConstraintLayout>

- android kotlin - Volley string request
- android kotlin - Chip center text
- android kotlin - EditText remove underline while typing
- android kotlin - EditText change cursor color programmatically
- android kotlin - EditText change underline color programmatically
- android kotlin - EditText hide keyboard after enter
- android kotlin - EditText hide keyboard click outside
- android kotlin - EditText enter key listener
- android kotlin - Switch button listener
- android kotlin - Material switch button
- android kotlin - Get raw resource uri
- android kotlin - Create ImageView programmatically
- android kotlin - ImageView rounded corners transparent
- android kotlin - Circular ImageView with border
- android kotlin - Circular ImageView programmatically