如何设置小部件的位置？

Question

[我想要的是让背景图像占据屏幕的一半以下，并在顶部添加一个Card Widget。从这里好。但是，当我插入另一个Card Widget时，它会改变位置，无法修复。

how it should be

what I have now

return SafeArea(
  child: Container(
    child: Column(
      children: [
        Stack(alignment: Alignment(0, 5.4), children: [
          ProfileBackgroundImage(
            backgroundImage:
                'https://images.unsplash.com/photo-1580331451062-99ff652288d7?ixlib=rb-1.2.1&ixid=eyJhcHBfaWQiOjEyMDd9&auto=format&fit=crop&w=1234&q=80',
          ),
          ProfileMainBubble(
              name: 'Laia Montés',
              photoProfile:
                  'https://images.unsplash.com/photo-1578680671705-0965e325b2ba?ixlib=rb-1.2.1&ixid=eyJhcHBfaWQiOjEyMDd9&auto=format&fit=crop&w=1233&q=80',
              profession: 'Singer and Guitarrist',
              description:
                  'I’m a musician who loves Pop and Rock. 🤘 Currently studying for being a lawyer, but what I truly want is to sing in the shower.',
              isFollowing: isFollowing)
        ]),
        StatisticsBubble(
            uploads: 36, reproductions: 2000000, hearts: 128000),
      ],
    ),
  ),
);

问题是我需要设置ProfileMainBubble和StatisticsBubble的位置，以便内容可以更改。那么，有没有Stack我都可以解决吗？

Answer 1

将其作为子元素放在Positioned（）小部件内：

Positioned(
  top: *modify here double values*,
  bottom: same with top and so on with left and right,
  child: ProfileBackgroundImage(
        backgroundImage:
            'https://images.unsplash.com/photo-1580331451062-99ff652288d7?ixlib=rb-1.2.1&ixid=eyJhcHBfaWQiOjEyMDd9&auto=format&fit=crop&w=1234&q=80',
      )
)

注意位置的窗口小部件将仅在Stack内部工作。

Answer 2

Widget build(BuildContext context) {
return Container(
    child: Align(
    alignment: FractionalOffset(0.5,0.5),
      child: Container(),
    )
);

}