Android画布Canvas绘图scale & translate,Kotlin
XML
<?xml version="1.0" encoding="utf-8"?>
<androidx.appcompat.widget.LinearLayoutCompat xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:background="@android:color/darker_gray"
android:orientation="vertical"
app:divider="@android:drawable/divider_horizontal_bright"
app:dividerPadding="5dp"
app:showDividers="beginning|middle|end">
<ImageView
android:id="@+id/iv"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="center_horizontal"
android:layout_margin="10dp"
android:background="@drawable/ic_launcher_background"
android:scaleType="fitCenter"
android:src="@mipmap/pic" />
<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="horizontal">
<ImageView
android:id="@+id/iv1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_margin="10dp"
android:background="@drawable/ic_launcher_background" />
<ImageView
android:id="@+id/iv2"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_margin="10dp"
android:background="@drawable/ic_launcher_background" />
</LinearLayout>
<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="horizontal">
<ImageView
android:id="@+id/iv3"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_margin="10dp"
android:background="@drawable/ic_launcher_background" />
<ImageView
android:id="@+id/iv4"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_margin="10dp"
android:background="@drawable/ic_launcher_background" />
</LinearLayout>
</androidx.appcompat.widget.LinearLayoutCompat>
Kotlin
import android.graphics.Bitmap
import android.graphics.Canvas
import android.graphics.drawable.BitmapDrawable
import android.os.Bundle
import android.widget.ImageView
import androidx.appcompat.app.AppCompatActivity
import androidx.lifecycle.lifecycleScope
import kotlinx.coroutines.Dispatchers
import kotlinx.coroutines.delay
import kotlinx.coroutines.launch
class MainActivity : AppCompatActivity() {
private var iv: ImageView? = null
private var iv1: ImageView? = null
private var iv2: ImageView? = null
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
setContentView(R.layout.activity_main)
iv = findViewById(R.id.iv)
iv1 = findViewById(R.id.iv1)
iv2 = findViewById(R.id.iv2)
lifecycleScope.launch(Dispatchers.Main) {
delay(500)
f1()
f2()
}
}
private fun f1() {
val bitmap = ((iv?.drawable as BitmapDrawable).bitmap.copy(Bitmap.Config.ARGB_8888, true))
val canvas = Canvas(bitmap)
val left = 50f
val top = 200f
canvas.scale(0.5f, 0.3f)
canvas.translate(left, top)
canvas.drawBitmap(bitmap, left, top, null)
iv1?.setImageBitmap(bitmap)
}
private fun f2() {
val bitmap = ((iv?.drawable as BitmapDrawable).bitmap.copy(Bitmap.Config.ARGB_8888, true))
val canvas = Canvas(bitmap)
val left = 50f
val top = 200f
canvas.scale(0.8f, 0.2f)
canvas.translate(left, top)
canvas.drawBitmap(bitmap, left, top, null)
iv2?.setImageBitmap(bitmap)
}
}