IOS上的不透明边框颜色无法正确渲染

Question

我对items_str = input('What is on your shopping list today? (Enter elements separated by a comma) ') #take input from the user items = items_str.replace(" ", "") #to remove whitespaces items = items.split(',') #creating an array of the items total = 0 for item in items: total = total + int(input("What is the estimated cost for {0}? Enter estimated cost here: ".format(item))) print("Total estimated cost for ", items_str, " is ", total) 组件使用以下样式：

View

在Android上，它按预期方式呈现，但似乎Alpha值未应用于IOS。渲染结果如下：

Android：

IOS：

任何人都可以解释这一点，并且有办法解决吗？谢谢。