如何根据位置更改 UIPickerView 标题文本颜色
How to change UIPickerView title text color based on position
我想设置一个UIPickerView,让选中的行标题(中间)为蓝色,上下两行的文本颜色为黑色,其他行的文本颜色为灰色..
所以它看起来像这样
在 swift 中有什么方法可以做到这一点吗?
是的,是的。下面的例子是一个组件。
var pickerArray = [String]()
var selectedRow: Int {
return pickerView.selectedRow(inComponent: 0)
}
func pickerView(_ pickerView: UIPickerView, didSelectRow row: Int, inComponent component: Int) {
pickerView.reloadComponent(component)
}
func pickerView(_ pickerView: UIPickerView, attributedTitleForRow row: Int, forComponent component: Int) -> NSAttributedString? {
var color = UIColor.gray
if row == selectedRow {
color = UIColor.blue
} else if selectedRow == row - 1 || selectedRow == row + 1 {
color = UIColor.black
}
return NSAttributedString(string: pickerArray[row], attributes: [NSAttributedString.Key.foregroundColor: color])
}
也许它存在另一种方式,但我认为这就足够了:]
// 更新 1:不推荐
您可以从中覆盖 (hitTest:point:event) 和 return self,然后在 (touchesMoved:touches:event) 上重新加载组件。但是选择器上的滚动和触摸将不起作用。您将需要做其他事情:(
//更新2:结果:
@Deryck Lucian 更新答案:
func pickerView(_ pickerView: UIPickerView, viewForRow row: Int, forComponent component: Int, reusing view: UIView?) -> UIView {
let pickerLabel = UILabel()
pickerLabel.textColor = (row == pickerView.selectedRow(inComponent: component)) ? UIColor.red : UIColor.green
pickerLabel.text = List[row]
pickerLabel.textAlignment = .center
return pickerLabel
}
func pickerView(_ pickerView: UIPickerView, didSelectRow row: Int, inComponent component: Int) {
pickerView.reloadComponent(component)
}
我想设置一个UIPickerView,让选中的行标题(中间)为蓝色,上下两行的文本颜色为黑色,其他行的文本颜色为灰色..
所以它看起来像这样
在 swift 中有什么方法可以做到这一点吗?
是的,是的。下面的例子是一个组件。
var pickerArray = [String]()
var selectedRow: Int {
return pickerView.selectedRow(inComponent: 0)
}
func pickerView(_ pickerView: UIPickerView, didSelectRow row: Int, inComponent component: Int) {
pickerView.reloadComponent(component)
}
func pickerView(_ pickerView: UIPickerView, attributedTitleForRow row: Int, forComponent component: Int) -> NSAttributedString? {
var color = UIColor.gray
if row == selectedRow {
color = UIColor.blue
} else if selectedRow == row - 1 || selectedRow == row + 1 {
color = UIColor.black
}
return NSAttributedString(string: pickerArray[row], attributes: [NSAttributedString.Key.foregroundColor: color])
}
也许它存在另一种方式,但我认为这就足够了:]
// 更新 1:不推荐
您可以从中覆盖 (hitTest:point:event) 和 return self,然后在 (touchesMoved:touches:event) 上重新加载组件。但是选择器上的滚动和触摸将不起作用。您将需要做其他事情:(
//更新2:结果:
@Deryck Lucian 更新答案:
func pickerView(_ pickerView: UIPickerView, viewForRow row: Int, forComponent component: Int, reusing view: UIView?) -> UIView {
let pickerLabel = UILabel()
pickerLabel.textColor = (row == pickerView.selectedRow(inComponent: component)) ? UIColor.red : UIColor.green
pickerLabel.text = List[row]
pickerLabel.textAlignment = .center
return pickerLabel
}
func pickerView(_ pickerView: UIPickerView, didSelectRow row: Int, inComponent component: Int) {
pickerView.reloadComponent(component)
}