样本NG ImageView
:NG Rotated ImageView
在iOS中,我可以通过view.layer.allowsEdgeAntialiasing = true
轻松解决这个锯齿状的边缘问题。在Android中解决此问题的最佳方法是什么?
我已经尝试过的内容:
我参考了这篇帖子Bitmap not drawn anti-aliased并设置了android:layerType="software"
,但结果仍然不正确。
<ImageView
android:id="@+id/imageView2"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layerType="software"
android:rotation="5"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="parent"
app:srcCompat="@drawable/pic" />
预期结果:平滑的边缘(抗锯齿)
实际结果:边缘不光滑(锯齿状)
答案 0 :(得分:0)
因此,经过一段时间的尝试,这是我可以达到的最佳效果:
1)测试输出: NG vs OK
2)NG输出源
仅* xml(在ConstraintLayout下)
<ImageView android:layout_width="wrap_content"
android:layout_height="wrap_content"
app:layout_constraintTop_toTopOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintBottom_toBottomOf="parent"
android:id="@+id/test3"
app:srcCompat="@drawable/sampleImg"
android:rotation="5"/>
3)确定输出源
* xml(在ConstraintLayout下)
<test.ntfry.imageview_rotate_antialias.MyImageView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
app:layout_constraintTop_toTopOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintBottom_toBottomOf="parent"
android:id="@+id/test2"/>
*自定义ImageView类
class MyImageView : AppCompatImageView {
private val mPaint = Paint(Paint.ANTI_ALIAS_FLAG)
private val mMatrix = Matrix()
private var mRotatedBitmap: Bitmap? = null
private val mRotation = 5F
constructor(context: Context) : super(context, null) {
init()
}
constructor(context: Context, attrs: AttributeSet?) : super(context, attrs) {
init()
}
constructor(context: Context, attrs: AttributeSet?, defStyleAttr: Int) : super(context, attrs, defStyleAttr) {
init()
}
override fun onMeasure(widthMeasureSpec: Int, heightMeasureSpec: Int) {
super.onMeasure(widthMeasureSpec, heightMeasureSpec)
setMeasuredDimension(mRotatedBitmap!!.width, mRotatedBitmap!!.height)
}
override fun onDraw(canvas: Canvas?) {
super.onDraw(canvas)
canvas?.drawBitmap(mRotatedBitmap!!, 0f, 0f, mPaint)
}
private fun init() {
// https://stackoverflow.com/questions/14378573/bitmap-not-drawn-anti-aliased
setLayerType(LAYER_TYPE_SOFTWARE, null)
// get source image and set-apply rotation through matrix
val sourceBitmap = BitmapFactory.decodeResource(resources, R.drawable.sampleImg)
mMatrix.postRotate(mRotation)
mRotatedBitmap = Bitmap.createBitmap(sourceBitmap, 0, 0, sourceBitmap.width, sourceBitmap.height, mMatrix, true)
}
}
4)如果您有更好的解决方案,请务必发表评论/分享您的想法!谢谢^^