Addings對UIView的兩個視圖

Question

我有一個故事板文件，我添加了一個UITableView和一個UIView。 UIView是我試圖做一個自定義頭，這將是半透明的，因此tableview將通過它可見（我不知道這是甚至可能的，因爲我是一個新手，這是我的第一個iPhone應用程序）。

處理與我的ViewController類，所有的連接後，當我運行的代碼，我給了我這個錯誤：

Unable to simultaneously satisfy constraints. 
Probably at least one of the constraints in the following list is one you don't want.   
Try this: (1) look at each constraint and try to figure out which you don't expect; (2) find the code that added the unwanted constraint or constraints and fix it. (Note: If you're seeing NSAutoresizingMaskLayoutConstraints that you don't understand, refer to the documentation for the UIView property translatesAutoresizingMaskIntoConstraints) 
(
"<NSAutoresizingMaskLayoutConstraint:0x8988060 h=--& v=--& V:[UIView:0x7574100(460)]>", 
"<NSLayoutConstraint:0x7574780 V:|-(0)-[UIView:0x75742b0] (Names: '|':UIView:0x7574100  )>", 
"<NSLayoutConstraint:0x7574700 V:[UIView:0x75742b0]-(494)-| (Names: '|':UIView:0x7574100)>" 
) 

Will attempt to recover by breaking constraint 
<NSLayoutConstraint:0x7574700 V:[UIView:0x75742b0]-(494)-| (Names: '|':UIView:0x7574100 )> 

Break on objc_exception_throw to catch this in the debugger. 
The methods in the UIConstraintBasedLayoutDebugging category on UIView listed in <UIKit/UIView.h> may also be helpful. 

爲什麼發生這種情況會有所幫助的任何想法。謝謝。

Answer 1

您已經在界面構建器中配置了一個不可能的狀態，如消息所示，您擁有的佈局約束不能一次全部滿足。當你是新的，我會建議禁用自動佈局約束（去文檔選項卡 - 最左邊的選項卡 - 在界面生成器，並取消選中自動佈局）這將讓你擺脫這個問題

是的，你可以有兩個視圖彼此之間，你只需要玩alpha值來配置半透明