view.getDrawingCache（）在Android API 28中已弃用

Question

在android API 28 view.getDrawingCache()中已弃用。是否有任何更新的解决方案可在android中生成特定视图的位图。

Answer 1

1. 使用画布
2. 像素Api

---

Canvas Example

RelativeLayout view = (RelativeLayout)findViewById(R.id.relativelayout);
Bitmap bitmap = Bitmap.createBitmap(view.getWidth(), view.getHeight(), Bitmap.Config.ARGB_8888);
Canvas canvas = new Canvas(bitmap);
Drawable bgDrawable = view.getBackground();
if (bgDrawable != null) {
    bgDrawable.draw(canvas);
} else {
    canvas.drawColor(Color.WHITE);
}
view.draw(canvas);

PixelCopy Api

https://stackoverflow.com/a/52985554/9909365

更多

https://developer.android.com/reference/android/graphics/Bitmap

https://developer.android.com/reference/android/graphics/Canvas

Answer 2

我找到了一种使用PixelCopy API将视图作为位图检索的方法。二手Kotlin

fun getBitmapFromView(view: View, activity: Activity, callback: (Bitmap) -> Unit) {
    activity.window?.let { window ->
        val bitmap = Bitmap.createBitmap(view.width, view.height, Bitmap.Config.ARGB_8888)
        val locationOfViewInWindow = IntArray(2)
        view.getLocationInWindow(locationOfViewInWindow)
        try {
            PixelCopy.request(window, Rect(locationOfViewInWindow[0], locationOfViewInWindow[1], locationOfViewInWindow[0] + view.width, locationOfViewInWindow[1] + view.height), bitmap, { copyResult ->
                if (copyResult == PixelCopy.SUCCESS) {
                    callback(bitmap)
                }
                // possible to handle other result codes ...
            }, Handler())
        } catch (e: IllegalArgumentException) {
            // PixelCopy may throw IllegalArgumentException, make sure to handle it
            e.printStackTrace()
        }
    }
}

Answer 3

从官方文档getDrawingCache()开始，您应该使用PixelCopy API。

Answer 4

尝试一下：

    private fun convertViewToDrawable(view: View): Bitmap {
    val spec = View.MeasureSpec.makeMeasureSpec(0, View.MeasureSpec.UNSPECIFIED)
    view.measure(spec, spec)
    view.layout(0, 0, view.measuredWidth, view.measuredHeight)
    val b = Bitmap.createBitmap(view.measuredWidth, view.measuredHeight,
            Bitmap.Config.ARGB_8888)
    val c = Canvas(b)
    c.translate((-view.scrollX).toFloat(), (-view.scrollY).toFloat())
    view.draw(c)
    return b
}

Answer 5

非常精确的代码。

private fun convertViewToDrawable(view: View): Bitmap {
        val b = Bitmap.createBitmap(view.measuredWidth, view.measuredHeight,
            Bitmap.Config.ARGB_8888)
        val c = Canvas(b)
        c.translate((-view.scrollX).toFloat(), (-view.scrollY).toFloat())
        view.draw(c)
        return b
    }

Answer 6

其他一些Kotlin代码（ScrollView情况）

val ScrollView.bitmap: Bitmap
get() {
    val bitmap = Bitmap.createBitmap(width, getChildAt(0).height, Bitmap.Config.RGB_565)
    with(Canvas(bitmap)) {
        val background = background
        if (background != null) {
            background.draw(this)
        } else {
            drawColor(Color.WHITE)
        }
        draw(this)
    }
    return bitmap
}