我有一个用于聊天页面的collectionView.我创建了一个名为TextChatCollectionViewCell的UICollectionViewCell子类.
我有另一个类填充我的集合视图并为每个项指定一个CGSize(遵循UICollectionViewDelegateFlowLayout和UICollectionViewDataSource协议).

我滚动时单元格框架大小正确但是子视图的框架大小错误,可能是因为dequeueReusableCell返回另一个单元格的实例并且子视图没有重新加载,我试图调用layoutIfNeeded()来强制再次绘制子视图的布局但是它没有效果.

我的单元格的xib文件有约束：

我填写并返回单元格的代码：

public func collectionView(_ collectionView: UICollectionView,cellForItemAt indexPath: IndexPath) -> UICollectionViewCell {
    guard let cell = self.manager.collectionView.dequeueReusableCell(withReuseIdentifier: "TextChatCollectionViewCell",for: indexPath) as? TextChatCollectionViewCell else {
        return UICollectionViewCell()
    }

    self.fillCellUsingMessageUUID(cell,self.messagesUUIDs[indexPath.row]) // Hide labelDate (set height to 0 for the moment),fill UITextView etc...


    print("=================\(self.messagesUUIDs[indexPath.row])===================")
    print("Cell text : " + cell.textMessage.text)
    print("Cell frame size : " + cell.frame.size.debugDescription)
    print("UITextView frame size : " + cell.textMessage.frame.size.debugDescription)
    print("UITextView parent size : " + cell.textBackgroundView.frame.size.debugDescription)
    print("Cell content view frame size : " + cell.globalView.frame.size.debugDescription)
    print("====================================")
    return cell
}

我的调试输出：

=================B00C74D6-C3F1-4039-948B-0BAC59DC0D83===================

Cell text : "Ggg"
Cell frame size : (320.0,80.0) // Expected size
UITextView frame size : (240.0,59.5) // Wrong height
UITextView parent size : (240.0,59.5) // Wrong height
Cell content view frame size : (320.0,59.5) // Wrong height
====================================
=================2704FFF5-17D1-4E0E-9399-DD7EB4C60D36===================
Cell text : "Zyehdhzhdhdhzhejajeksvshdjajdjhhhjhhjjhhhhthhytgjuhjjyghjuyghhuygghuutghjutghkiygvcwqazdxcfeerggvbhtyjjnkkuilloomppolpôkkjjîîîukhgkurghhhhhgoohgosohsohdohsohsohshowlhdlhslhslhsglslydlgsotwyod [...]"
Cell frame size : (320.0,411.5) // Expected size
UITextView frame size : (240.0,59.5) // Wrong height

预期产量：

=================B00C74D6-C3F1-4039-948B-0BAC59DC0D83===================

Cell text : "Ggg"
Cell frame size : (320.0,80.0)
UITextView frame size : (240.0,80.0)
UITextView parent size : (240.0,80.0)
Cell content view frame size : (320.0,80.0)
====================================
=================2704FFF5-17D1-4E0E-9399-DD7EB4C60D36===================
Cell text : "Zyehdhzhdhdhzhejajeksvshdjajdjhhhjhhjjhhhhthhytgjuhjjyghjuyghhuygghuutghjutghkiygvcwqazdxcfeerggvbhtyjjnkkuilloomppolpôkkjjîîîukhgkurghhhhhgoohgosohsohdohsohsohshowlhdlhslhslhsglslydlgsotwyod [...]"
Cell frame size : (320.0,411.5) 
UITextView frame size : (240.0,411.5) 
UITextView parent size : (240.0,411.5)
Cell content view frame size : (320.0,411.5)