The vertically scrolling `ScrollView` should not contain another vertically scrolling widget (`ListView`)
时间: 2024-01-27 17:02:56 浏览: 29
这个警告提示你不应该将一个`ListView`放在一个`ScrollView`中,因为它们都是垂直滚动的控件,这样可能会导致滚动冲突,出现意想不到的错误。
如果你需要在一个可滚动的视图中显示一个列表,推荐使用`ListView`本身的滚动能力,而不是将它放入一个`ScrollView`中。如果你需要在`ListView`之上或之下放置其他的控件,你可以使用`ListView`的`header`和`footer`属性来实现。如果你需要在`ListView`中间插入其他类型的视图,你可以使用`ListView`的`builder`属性,将其作为一个特殊的列表项来显示。
相关问题
This view is not constrained vertically: at runtime it will jump to the top unless you add a vertical constraint
这个问题是关于Android布局的。意思是说一个view在竖直方向上没有被限制,因此在运行时它会跳到顶部,除非你添加一个竖直方向上的限制。解决方法是在xml文件中为该view添加一个竖直方向上的约束条件,例如使用layout_constraintTop_toBottomOf或者layout_constraintBottom_toTopOf。这样就可以避免在运行时出现布局问题了。
write an HTML /CSS code to align image vertically in a division that spans vertically on the whole webpage
Here's an example of HTML/CSS code that aligns an image vertically in a division that spans vertically on the whole webpage:
HTML:
```
<body>
<div class="vertical-container">
<img src="your-image.jpg" alt="Your Image">
</div>
</body>
```
CSS:
```
body {
margin: 0;
padding: 0;
}
.vertical-container {
height: 100vh; /* sets the height of the container to 100% of the viewport height */
display: flex;
justify-content: center; /* centers the image horizontally */
align-items: center; /* centers the image vertically */
}
.vertical-container img {
max-width: 100%; /* ensures the image doesn't exceed the width of the container */
max-height: 100%; /* ensures the image doesn't exceed the height of the container */
}
```
In this example, we create a `div` element with a class of `vertical-container` and an `img` element inside it. We use CSS to set the height of the `div` to `100vh`, which sets the height of the container to 100% of the viewport height. We then use `display: flex` to make the container a flex container and `justify-content: center` and `align-items: center` to center the image both horizontally and vertically within the container. Finally, we use `max-width: 100%` and `max-height: 100%` on the `img` element to ensure that the image doesn't exceed the width or height of the container.
This code will align the image vertically in the division that spans vertically on the whole webpage.