Wednesday, February 19, 2020

android kotlin ktx - View to bitmap example

MainActivity.kt

package com.example.jetpack

import android.graphics.Bitmap
import android.os.Bundle
import androidx.appcompat.app.AppCompatActivity
import androidx.core.view.drawToBitmap
import kotlinx.android.synthetic.main.activity_main.*


class MainActivity : AppCompatActivity() {

    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        setContentView(R.layout.activity_main)

        button.setOnClickListener {
            // draw a bitmap from card view
            val b:Bitmap = cardView.drawToBitmap(Bitmap.Config.ARGB_8888)

            // show to generated bitmap to image view
            imageView.setImageBitmap(b)
        }
    }
}
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:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context=".MainActivity">
    <ImageView
        android:id="@+id/imageView"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginStart="8dp"
        android:layout_marginTop="16dp"
        android:layout_marginEnd="8dp"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintHorizontal_bias="0.501"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toBottomOf="@+id/button"
        tools:srcCompat="@tools:sample/avatars[13]" />
    <Button
        android:id="@+id/button"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginTop="16dp"
        android:backgroundTint="#333399"
        android:text="Card To Bitmap"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toBottomOf="@+id/cardView" />
    <androidx.cardview.widget.CardView
        android:id="@+id/cardView"
        android:layout_width="0dp"
        android:layout_height="wrap_content"
        android:layout_marginStart="16dp"
        android:layout_marginTop="24dp"
        android:layout_marginEnd="8dp"
        android:elevation="8dp"
        app:cardBackgroundColor="#3B2F2F"
        app:cardCornerRadius="4dp"
        app:contentPadding="12dp"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toTopOf="parent">
        <androidx.constraintlayout.widget.ConstraintLayout
            android:layout_width="match_parent"
            android:layout_height="wrap_content">
            <TextView
                android:id="@+id/textView"
                android:layout_width="0dp"
                android:layout_height="wrap_content"
                android:background="#B0BF1A"
                android:fontFamily="monospace"
                android:gravity="center"
                android:padding="16dp"
                android:text="View To Bitmap"
                android:textAppearance="@style/TextAppearance.AppCompat.Large"
                android:textSize="35sp"
                app:layout_constraintBottom_toBottomOf="parent"
                app:layout_constraintEnd_toEndOf="parent"
                app:layout_constraintStart_toStartOf="parent"
                app:layout_constraintTop_toTopOf="parent" />
        </androidx.constraintlayout.widget.ConstraintLayout>
    </androidx.cardview.widget.CardView>
</androidx.constraintlayout.widget.ConstraintLayout>
build.gradle dependencies[add]

// android ktx
implementation 'androidx.core:core-ktx:1.2.0'
More android examples