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如何实现位图函数

kotlin

wenus · 技术社区 · 4 年前

我在ImageView中有一个自定义扩展,用于半径特定的角:

    bitmap: Bitmap,
    topLeftCorner: Float, topRightCorner: Float,
    bottomRightCorner: Float, bottomLeftCorner: Float
): Bitmap? {
    val output = Bitmap.createBitmap(
        bitmap.width, bitmap.height,
        Bitmap.Config.ARGB_8888
    )
    val canvas = Canvas(output)
    val color = Color.WHITE
    val paint = Paint()
    val rect = Rect(0, 0, bitmap.width, bitmap.height)
    val rectF = RectF(rect)
    val path = Path()
    val radii = floatArrayOf(
        topLeftCorner, topLeftCorner,
        topRightCorner, topRightCorner,
        bottomRightCorner, bottomRightCorner,
        bottomLeftCorner, bottomLeftCorner
    )
    paint.isAntiAlias = true
    canvas.drawARGB(0, 0, 0, 0)
    paint.color = color
    path.addRoundRect(rectF, radii, Path.Direction.CW)
    canvas.drawPath(path, paint)
    paint.xfermode = PorterDuffXfermode(PorterDuff.Mode.SRC_IN)
    canvas.drawBitmap(bitmap, rect, rect, paint)
    return output
}

现在我正试图开始使用它,或者它真的有效,但我无法实现它。我无法将位图导入此函数。我该怎么做?问题是:

val bitmap = <--- how get bitmap???

            binding.imgItem.createRoundedRectBitmap(
                bitmap,
                25.toFloat(),
                25.toFloat(),
                10.toFloat(),
                8.toFloat()
            )```

Any tips?

0 回复 | 直到 4 年前

Muhammad Bilal 4 年前

步骤:1创建一个类(任何名称)

class Utils {
companion object {

    fun createRoundedRectBitmap(
        bitmap: Bitmap,
        topLeftCorner: Float, topRightCorner: Float,
        bottomRightCorner: Float, bottomLeftCorner: Float
    ): Bitmap? {
        val output = Bitmap.createBitmap(
            bitmap.width, bitmap.height,
            Bitmap.Config.ARGB_8888
        )
        val canvas = Canvas(output)
        val color = Color.WHITE
        val paint = Paint()
        val rect = Rect(0, 0, bitmap.width, bitmap.height)
        val rectF = RectF(rect)
        val path = Path()
        val radii = floatArrayOf(
            topLeftCorner, topLeftCorner,
            topRightCorner, topRightCorner,
            bottomRightCorner, bottomRightCorner,
            bottomLeftCorner, bottomLeftCorner
        )
        paint.isAntiAlias = true
        canvas.drawARGB(0, 0, 0, 0)
        paint.color = color
        path.addRoundRect(rectF, radii, Path.Direction.CW)
        canvas.drawPath(path, paint)
        paint.xfermode = PorterDuffXfermode(PorterDuff.Mode.SRC_IN)
        canvas.drawBitmap(bitmap, rect, rect, paint)
        return output
    }

}
}

步骤:2你可以这样得到位图

val bitmap = AppCompatResources.getDrawable(this, R.drawable.imgItem)?.toBitmap()

步骤:3

binding.imgItem.setImageBitmap(bitmap?.let {
            ProgressUtils.loadBitmap(
                it, 50.toFloat(),
                50.toFloat(),
                20.toFloat(),
                8.toFloat()
            )
        })