本文介绍了swift:与“UIPickerView"不同的处理方法，对大家解决问题具有一定的参考价值，需要的朋友们下面随着小编来一起学习吧！
问题描述
我尝试了以下适用于 Obj-C 的方法，但在 swift 中出现错误:'(@lvalue UIPickerView!, titleForRow: Int, forComponent: Int) -> $T7' 与'UIPickerView' 不同
I tried the following method which works in Obj-C, but I got error in swift:'(@lvalue UIPickerView!, titleForRow: Int, forComponent: Int) -> $T7' is not identical to ‘UIPickerView’
func pickerView(pickerView: UIPickerView, viewForRow row: Int, forComponent component: Int, reusingView view: UIView!) -> UIView
{
var pickerLabel = UILabel()
pickerLabel.textColor = UIColor.whiteColor()
pickerLabel.text = pickerView(pickerView, titleForRow: row, forComponent: component)
return pickerLabel
}
这里是 obj-c 的工作代码:
here is the obj-c working codes:
- (UIView *)pickerView:(UIPickerView *)pickerView viewForRow:(NSInteger)row forComponent:(NSInteger)component reusingView:(UIView *)view{
UILabel* pickerLabel = (UILabel*)view;
if (!pickerLabel){
pickerLabel = [[UILabel alloc] init];
[pickerLabel setFont:[UIFont fontWithName:@"Helvetica Neue Bold Italic" size:25]];
}
pickerLabel.textAlignment = NSTextAlignmentCenter;
pickerLabel.textColor = [UIColor whiteColor];
pickerLabel.text=[self pickerView:pickerView titleForRow:row forComponent:component];
return pickerLabel;
}
- (NSString *)pickerView:(UIPickerView *)pickerView titleForRow:(NSInteger)row forComponent:(NSInteger)component {
if (component == 0){
if ([unitType isEqualToString:@"MS"]) {
return [thickness objectAtIndex:row];
}else{
NSString *th = [thickness objectAtIndex:row];
float tt = [th floatValue]*0.039370078740157;
NSString *new_th = [NSString stringWithFormat:@"%2.2f",tt];
return new_th;
}
}
if(component ==1){
if ([unitType isEqualToString:@"MS"]) {
return [weight_data objectAtIndex:row];
}else{
NSString *wei = [weight_data objectAtIndex:row];
float ww = [wei floatValue]*2.205;
NSString *new_wei = [NSString stringWithFormat:@"%3.1f",ww];
return new_wei;
}
}
推荐答案
我认为您想打印从 UIPickerView 中选择索引的数据，但我认为您这样做是错误的.
I think you want to print the data from which index is selected from UIPickerView,But I think you are doing this wrong way.
这里有两个例子:
var states : [String]!
func pickerView(pickerView: UIPickerView, viewForRow row: Int,
forComponent component: Int, reusingView view: UIView!) -> UIView {
var lab : UILabel
if let label = view as? UILabel {
lab = label
println("reusing label")
} else {
lab = MyLabel()
println("making new label")
}
// You can set text this way where states is an array of string.
lab.text = self.states[row]
lab.backgroundColor = UIColor.clearColor()
lab.sizeToFit()
return lab
}
}
参考来自HERE
func pickerView(pickerView: UIPickerView, viewForRow row: Int, forComponent component: Int, reusingView view: UIView!) -> UIView {
var pickerLabel = view as UILabel!
if view == nil { //if no label there yet
pickerLabel = UILabel()
//color the label's background
let hue = CGFloat(row)/CGFloat(pickerData.count)
pickerLabel.backgroundColor = UIColor(hue: hue, saturation: 1.0, brightness: 1.0, alpha: 1.0)
}
let titleData = pickerData[row]
let myTitle = NSAttributedString(string: titleData, attributes: [NSFontAttributeName:UIFont(name: "Georgia", size: 26.0)!,NSForegroundColorAttributeName:UIColor.blackColor()])
//This way you can set text for your label.
pickerLabel!.attributedText = myTitle
return pickerLabel
}
希望对您有所帮助.
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