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How to fill with color only the icon on canvas,without the background android studio

I want to change the color of my png,i want to fill it with color,so i thought about creating a bitmap from the png,placing it on a canvas and drawing the canvas,but it is drawing the whole canvas,like this,so my icons are covered completely
This is my code:
private fun testResizeImg(imgRes: Int): BitmapDescriptor {
var bm = BitmapFactory.decodeResource(resources, imgRes)
bm = Bitmap.createScaledBitmap(bm, (bm.width * 0.1).toInt(), (bm.height * 0.1).toInt(), true)
val canvas = Canvas(bm)
val paint = Paint()
paint.color = Color.BLUE
canvas.drawPaint(paint)
return BitmapDescriptorFactory.fromBitmap(bm)
}
What is the best approach to do this,i have a png and i want to paint it.

You can try something like that ? (not tested)
You can use theColor Filter to change the icon's color at runtime.
Then you transform the drawable into Bitmap.
private fun testResizeImg(#DrawableRes imgRes: Int): BitmapDescriptor {
val mIcon = ContextCompat.getDrawable(getActivity(), imgRes)
mIcon?.colorFilter = BlendModeColorFilterCompat.createBlendModeColorFilterCompat(Color.BLUE, BlendModeCompat.SRC_ATOP)
var bm : Bitmap = (mIcon as BitmapDrawable).bitmap
bm = Bitmap.createScaledBitmap(bm, (bm.width * 0.1).toInt(), (bm.height * 0.1).toInt(), true)
return BitmapDescriptorFactory.fromBitmap(bm)
}
Note that the #DrawableRes is here to help for the code inspection

private fun testResizeImg(imgRes: Int): BitmapDescriptor {
var bm = BitmapFactory.decodeResource(resources, imgRes)
bm = Bitmap.createScaledBitmap(bm, (bm.width * 0.1).toInt(), (bm.height * 0.1).toInt(), true)
val canvas = Canvas(bm)
canvas.drawBitmap(bm,0F,0F,null)
return BitmapDescriptorFactory.fromBitmap(bm)
}

how can i improve these functions to bind bitmaps on recyclerView?

I have a set of two functions that i use to bind images to a recyclerview, one is for converting a string (base64) to a bitmap, the other function is to round the corners of said image.
//convert string to bitmap
fun stringToBitMap( encodedString: String): Bitmap? {
println("string to bitmap is being called")
return try {
val encodeByte: ByteArray = Base64.decode(encodedString, Base64.DEFAULT)
BitmapFactory.decodeByteArray(encodeByte, 0, encodeByte.size)
} catch (e: Exception) {
println("Failed to convert string to bitmap")
e.message
null
}
}
//round corners
fun getRoundedCornerBitmap(bitmap: Bitmap, pixels: Int): Bitmap {
println("get rounded corners is being called")
val output = Bitmap.createBitmap(bitmap.width, bitmap.height, Bitmap.Config.ARGB_8888)
val canvas = Canvas(output)
val color = -0xbdbdbe
val paint = Paint()
val rect = Rect(0, 0, bitmap.width, bitmap.height)
val rectF = RectF(rect)
val roundPx = pixels.toFloat()
paint.isAntiAlias = true
canvas.drawARGB(0, 0, 0, 0)
paint.color = color
canvas.drawRoundRect(rectF, roundPx, roundPx, paint)
paint.xfermode = PorterDuffXfermode(PorterDuff.Mode.SRC_IN)
canvas.drawBitmap(bitmap, rect, rect, paint)
return output
}
and i anotate my final function with BindingAdapter, then i call the function from the xml file
#BindingAdapter("poster")
fun image (view: ImageView, image: String) {
return view.setImageBitmap(stringToBitMap(image)?.let { getRoundedCornerBitmap(it, 10) })
}
it works, but the performance is poor in some devices, im debbugin my app in a low resource phone (samsung SM-J106B) and the spikes of cpu usage are 35% when scrolling fast(my images are not high res, only 400x400), also the recyclerview keeps calling these functions and it makes the scrolling kinda sluggish. So the question is, how can i improve my functions?
pd: im a complete newbie :(

I ended up using the glide like this:
fun poster(view: ImageView, image: String) {
val imageByteArray: ByteArray = Base64.decode(image, Base64.DEFAULT)
val round = RequestOptions
.bitmapTransform(RoundedCorners(14))
Glide.with(view)
.load(imageByteArray)
.apply(round)
.into(view)
}
performance is better now :D

Take screenshot from io.flutter.embedding.android.flutterview

I want to programmatically take screenshots from my FlutterView in Android.
When it was io.flutter.view.FlutterView I just use getBitmap()
But how can I make screenshot from io.flutter.embedding.android.FlutterView ?
I tried following code but this does not work:
private fun getBitmapFromNewEmbeddedFlutterView(flutterView: io.flutter.embedding.android.FlutterView): Bitmap {
val bitmap = Bitmap.createBitmap(
flutterView.width,
flutterView.height,
Bitmap.Config.ARGB_8888
)
val canvas = Canvas(bitmap)
flutterView.layout(
0,
0,
flutterView.measuredWidth,
flutterView.measuredHeight
)
flutterView.draw(canvas)
return bitmap
}

Android how to use BlurMaskFilter.Blur.NORMAL to a mask bitmap in Canvas

I have a mask bitmap with alpha channel,I want use it to cover origin bitmap and make sure edge feather.I try to use below code,but failed:
AndroidManifest.xml:android:hardwareAccelerated="false"
fun featherEdge(maskBm: Bitmap): Bitmap {
if (maskBm == null) return maskBm
val canvasBmp = Bitmap.createBitmap(maskBm.width, maskBm.height, ARGB_8888)
val canvas = Canvas(canvasBmp)
// canvas.isHardwareAccelerated = false
val paint = Paint()
paint.isAntiAlias = true
paint.isDither = true
paint.maskFilter = BlurMaskFilter(20f, BlurMaskFilter.Blur.NORMAL);
canvas.drawBitmap(maskBm, 0f, 0f, paint)
return canvasBmp
}
result bitmap edge is rough:
what I want result:
Question2:
Because android:hardwareAccelerated="false",many function can't work,how to make android:hardwareAccelerated="false" only to off-Screen canvas?
Thank you.

Native Crash in getting bitmap from resource

I have a native crash:
A/libc: invalid address or address of corrupt block 0x55766f1b00 passed to try_realloc_chunk
A/libc: Fatal signal 11 (SIGSEGV), code 1, fault addr 0xdeadbaad in tid 32219 (onPool-worker-1)
when executing the drawable.draw(canvas) line in the following method:
fun getBitmapFromResource(context: Context, imageRes: Int, iconSize: Float = CATEGORY_ICON_SIZE): Bitmap? {
val drawable = ContextCompat.getDrawable(context, imageRes)
if (drawable is BitmapDrawable) {
return drawable.bitmap
}
val size = GraphicsUtils.toPx(context, iconSize)
val bitmap = Bitmap.createBitmap(size, size, Bitmap.Config.ARGB_8888)
val canvas = Canvas(bitmap)
drawable!!.setBounds(0, 0, canvas.width, canvas.height)
drawable.draw(canvas) // crash!!
return bitmap
}
The drawable is VectorDrawable implementation. I am executing this code on a background thread in a coroutine.
I added vectorDrawables.useSupportLibrary = true to build.gradle file, but it did not help.
I need bitmap object because from its width and height I draw a custom chart and I need to perform size calculations there.
I had the suspicion that multi-threading might break the process, so I added this code in the runBlocking section (still on a background thread) - no effect.
Any ideas how to fix this?

After several hours of investigation, I fixed the issue.
The problem seems to be that more than one coroutine was entering the method at the same time. I used Mutex to make sure only one coroutine can be inside the method.
object UIUtilsSingleton {
private val mutex = Mutex()
suspend fun getBitmapFromResource(context: Context, imageRes: Int): Bitmap? {
var bitmap: Bitmap? = null
mutex.withLock {
val iconSize = 42f
val drawable = ContextCompat.getDrawable(context, imageRes)
if (drawable is BitmapDrawable) {
return drawable.bitmap
}
val size = GraphicsUtils.toPx(context, iconSize)
bitmap = Bitmap.createBitmap(size, size, Bitmap.Config.ARGB_8888)
val canvas = Canvas(bitmap)
drawable!!.setBounds(0, 0, canvas.width, canvas.height)
drawable.draw(canvas)
}
return bitmap
}
}