xcode 自动布局：需要 y 位置或高度的约束
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Autolayout : Need constraints for y position or height
提问by Gaurav Pandey
I am trying to satisfying the constraint form a long time but getting above error i.e. is "Need constraints for y position or height" for Yellow View and Green View. Basically I have 2 UILabel (dynamic height) within UIView and UIImageView of 4:3 ratio within a Cell.
我试图长时间满足约束形式，但遇到错误，即黄色视图和绿色视图的“ y 位置或高度需要约束”。基本上我在一个单元格内的 UIView 和 UIImageView 中有 2 个 UILabel（动态高度），比例为 4:3。
And my applied constraint is
我应用的约束是
I am also including sample project herewith above issue.
我还在此处包含了具有上述问题的示例项目。
回答by Prashant Tukadiya
Just one Constraints required
只需要一个约束
Provide SubHeading label height>= (Greater than equal to) Constraints
提供副标题标签height>= ( Greater than equal to) 约束
Because of you have applied aspect ratio of UIImageViewof 4:3
so it required to fixed other items height and Y position before it apply a ratio to it.
By giving height to subheading Autolayout is able to calculate approx value min required in image ratio
由于您应用UIImageView了 4:3 的纵横比，因此在对其应用比例之前需要固定其他项目的高度和 Y 位置。通过为副标题提供高度，Autolayout 能够计算出图像比例所需的近似值 min
Hope it is helpful to you
希望对你有帮助
回答by sRoy
I am attaching two images, one is output and another one is the constraints of views (UILabel, UIImageView). For testing purpose, I put long texts in UILabel, after testing I reduced the text to 'Heading it is' and 'Sub heading it is'. Let me know, if its working of not.enter image description here
我附上两张图片，一张是输出，另一张是视图的约束（UILabel、UIImageView）。出于测试目的，我将长文本放在 UILabel 中，测试后我将文本缩减为“标题是”和“子标题是”。让我知道，如果它不起作用。请在此处输入图像描述
