Xcode iOS-如何使图像适合不同的屏幕尺寸

Question

I am making an iOS app. Basically several login fields with a logo on top. The storyboard should simply fit device screen width.

I have started with a Scroll View (to make sure everything is available when the keyboard pops up). The Scroll View has constraints: top 0, left 0, right 0.

Then I have put a Stack View in the Scroll View. It also has constraints: top 0, left 0, right 0.

I have added text fields and an Image View. The Image View also has constraints: top 0, left 0, right 0 and content mode "aspect fit". I want the logo to be simply resized to fit screen width. The PNG image has a "Dummy logo" text.

This is what I see in XCode (the same happens in the simulator and on a real device): The image keeps its original size and is clipped. What should I do to make the Image View follow screen width? Thank you

Answer 1

The problem was that my layout was broken . It is shown by the red dot in "file explorer" (top left). After clicking on the dot Xcode has shown me which properties don't make sense. Size of Scroll view contents were not fixed. I had to link the size of StackView and main View - I did that by selecting (hold Ctrl + click) both View and StackView in file explorer and then right clicking on them and adding equal height/width constraints (though I still have to verify that everything looks reasonable on different devices).

Constraining the ImageView to StackView had no effect, because StackView constraint was the size of ScrollView, which can hold any size, so effectively the size was not fixed to anything.