在運行時

Question

變化的UIButton類，所以我有兩個UIButton's，都連接到類LikeShape.swift

我有另一個類名爲LikeShapeDone.swift，我想這樣在運行時設置：

func collectionView(collectionView: UICollectionView, cellForItemAtIndexPath indexPath: NSIndexPath) -> UICollectionViewCell 
    { 
     let imageCell = collectionView.dequeueReusableCellWithReuseIdentifier("imageCell", forIndexPath: indexPath) as! PostsCollectionViewCell 

     if (likedBy[indexPath.row].containsObject((PFUser.currentUser()?.username)!)){ 
       // Post is liked by the current user 
       imageCell.likeButton = LikeShape() 
       imageCell.dislikeButton = LikeShapeDone() 
      } 
      if (dislikedBy[indexPath.row].containsObject((PFUser.currentUser()?.username)!)){ 
       // Post is disliked by the current user 
       imageCell.dislikeButton = LikeShapeDone() 
       imageCell.likeButton = LikeShape() 
      } 
      else{ 
       // Post is not liked by the current user 
      } 
     // <---- End ImageCell Row ----> 
     return imageCell 
    } 

但沒有任何反應..我100％確定當前用戶在likedBy和dislikedBy LikeShape類有黑色按鈕，而LikeShapeDone有紅色按鈕，但按鈕只是一直黑色......任何建議？

Answer 1

正如我在評論中推薦的那樣，我會爲您的按鈕創建1個類，您可以在哪裏直接在運行時設置按鈕的類型。例如：

public class LikeButton: UIButton { 

    public func setLike(type: String) { 

    switch(type) { 

    case "blue": 
     self.setBackgroundColor(UIColor.blueColor(), forState: .Normal) 
    break; 

    case "red": 
     self.setBackgroundColor(UIColor.redColor(), forState: .Normal) 
     break; 

    case "black": 
     self.setBackgroundColor(UIColor.blackColor(), forState: .Normal) 
     break; 

    case "white": 
     self.setBackgroundColor(UIColor.whiteColor(), forState: .Normal) 
     break; 

    default: 
    break 
    } 
} 

再次編輯：這隻有在您確實需要擴展當前UIButton時纔有意義。當你有多個參數時，這是有道理的，你不想每次都將它們設置到你的UIButton類。

您可以設置（當然）：

myButton.setBackgroundColor(UIColor.redColor(), forState: .Normal) //Any Color 

代碼頂級的用法：

myLikeButton = LikeButton(frame: CGRectMake(0,0,200,50)) 
myLikeButton.setLike("blue") 

或（在運行時）

myLikeButton.setLike("red")