由于自己桌面控件需要实现圆角+裁剪的图片显示，必须获取准确的AppWidget桌面控件宽高。查了百度一大堆资料都是不全的，然后上了下StackOverFlow终于找到答案并解决问题。

class WidgetSizeProvider(
    private val context: Context // Do not pass Application context
) {

    private val appWidgetManager = AppWidgetManager.getInstance(context)

    fun getWidgetsSize(widgetId: Int): Pair<Int, Int> {
        val isPortrait = context.resources.configuration.orientation == ORIENTATION_PORTRAIT
        val width = getWidgetWidth(isPortrait, widgetId)
        val height = getWidgetHeight(isPortrait, widgetId)
        val widthInPx = context.dip(width)
        val heightInPx = context.dip(height)
        return widthInPx to heightInPx
    }

    private fun getWidgetWidth(isPortrait: Boolean, widgetId: Int): Int =
        if (isPortrait) {
            getWidgetSizeInDp(widgetId, AppWidgetManager.OPTION_APPWIDGET_MIN_WIDTH)
        } else {
            getWidgetSizeInDp(widgetId, AppWidgetManager.OPTION_APPWIDGET_MAX_WIDTH)
        }

    private fun getWidgetHeight(isPortrait: Boolean, widgetId: Int): Int =
        if (isPortrait) {
            getWidgetSizeInDp(widgetId, AppWidgetManager.OPTION_APPWIDGET_MAX_HEIGHT)
        } else {
            getWidgetSizeInDp(widgetId, AppWidgetManager.OPTION_APPWIDGET_MIN_HEIGHT)
        }

    private fun getWidgetSizeInDp(widgetId: Int, key: String): Int = appWidgetManager.getAppWidgetOptions(widgetId).getInt(key, 0)

    private fun Context.dip(value: Int): Int = (value * resources.displayMetrics.density).toInt()

}