如何在 swift 中使我的 UIPickerView 多行显示？

Question

我有一个 UIPickerView，如何让它多行显示？我有一些长文本。

这是我的代码。

func pickerView(pickerView: UIPickerView, titleForRow row: Int, forComponent component: Int) -> String? {
    var returnResult: String = ""
    if pickerView.tag == 1 {
    //This picker has long text
        let position: UInt = UInt(row)
        returnResult = list.objectAtIndex(position).Description.Value;
    } else if pickerView.tag == 2 {
        returnResult =  questionTwoOptions[row]
    } else if pickerView.tag == 3 {
        returnResult = questionThreeOptions[row]
    } else {
        returnResult = ""
    }
    print(returnResult)
    return returnResult
}

这是我的 viewForRow 方法

func pickerView(pickerView: UIPickerView, viewForRow row: Int, forComponent component: Int, reusingView view: UIView?) -> UIView {
    let label = UILabel(frame: CGRectMake(0, 0, 400, 44));
    label.lineBreakMode = .ByWordWrapping;
    label.numberOfLines = 0;
    //view!.addSubview(label)
    return label;
}

Answer 1

您将不得不更改 rowHeightForComponent (UIPickerView)

类似于：

  func pickerView(pickerView: UIPickerView, rowHeightForComponent component: Int) -> CGFloat
    {
        return 70.0
    }

而且您将能够在多行中看到它，其余的一切您都做得很好。

Answer 2

您可以尝试使用自定义视图

func pickerView(pickerView: UIPickerView, viewForRow row: Int, forComponent component: Int, reusingView view: UIView?) -> UIView {
    let label = UILabel(frame: CGRectMake(0, 0, 400, 44));
    label.lineBreakMode = .ByWordWrapping;
    label.numberOfLines = 0;
    label.text = arr[row]
    label.sizeToFit()
    return label;
}

如果您的内容超过两行，您还可以设置行高

func pickerView(pickerView: UIPickerView, rowHeightForComponent component: Int) -> CGFloat {
    return 80
}

Answer 3

Swift 4

请记住 UILabel 是 UIView 的子类。
我们正在为 UIPickerView 创建视图，其他向视图提供文本的委托方法现在无关紧要。
在创建 UILabel 期间更改 height: 参数并调整 return 80.0 行高，如果需要更多 space。
不要忘记设置文本对齐等其他属性。

首先添加指示行高的委托方法。调整为最适合您的显示目的的值。

func pickerView(_ pickerView: UIPickerView, rowHeightForComponent component: Int) -> CGFloat {
    return 80.0
}

接下来添加委托方法来提供视图。

func pickerView(_ pickerView: UIPickerView, viewForRow row: Int, forComponent component: Int, reusing view: UIView?) -> UIView {
    let label: UILabel

    if let view = view {
        label = view as! UILabel
    }
    else {
        label = UILabel(frame: CGRect(x: 0, y: 0, width: pickerView.frame.width, height: 400))
    }

    label.text = myTitleStrings[row]
    label.lineBreakMode = .byWordWrapping
    label.numberOfLines = 0
    label.sizeToFit()

    return label
}

带有属性文本的示例

func pickerView(_ pickerView: UIPickerView, viewForRow row: Int, forComponent component: Int, reusing view: UIView?) -> UIView {
    let label: UILabel

    if let view = view {
        label = view as! UILabel
    }
    else {
        label = UILabel(frame: CGRect(x: 0, y: 0, width: pickerView.frame.width, height: 400))
    }

    let title = myTitleStrings[row]
    let attributes = [NSAttributedStringKey.foregroundColor: UIColor.white,
                      NSAttributedStringKey.font: UIFont(name: "HelveticaNeue", size: 18.0)!]
    label.attributedText = NSAttributedString(string: title, attributes: attributes)
    label.lineBreakMode = .byWordWrapping
    label.numberOfLines = 0
    label.sizeToFit()

    return label
}

如何在 swift 中使我的 UIPickerView 多行显示？

How can I make my UIPickerView Multiline in swift?

uipickerview

ios

swift

Swift 4

带有属性文本的示例