iphone - 更改特定行颜色 uipicker

Question

我有以下问题:我可以更改 uipicker 中各行的文本颜色，但不能更改我想要的特定行的文本颜色，选择器变得很困惑，很多文本标签变成蓝色。

- (UIView *)pickerView:(UIPickerView *)pickerView viewForRow:(NSInteger)row forComponent:(NSInteger)component reusingView:(UIView *)view {
    UILabel *retval = (UILabel*)view;
    if (!retval) {
        retval= [[UILabel alloc] initWithFrame:CGRectMake(0.0f, 0.0f, [pickerView rowSizeForComponent:component].width, [pickerView rowSizeForComponent:component].height)];
    }
    retval.text = [arraySubSistemasDeSaude objectAtIndex:row];
    if(pickerView == subSistemaSaudePicker) {

        if ([retval.text isEqualToString:@"Seguros de saúde"]) {

            NSLog(@"ROW=%d",row);
            [retval setTextColor:[UIColor blueColor]];
        }
        if ([retval.text isEqualToString:@"Sistemas de Saúde e Equiparados"]) {
           NSLog(@"ROW=%d",row);
       [retval setTextColor:[UIColor blueColor]];

         if ([retval.text isEqualToString:@"Seguradoras-Acidentes de Trabalho, viação/pessoais e vida"]) {
            NSLog(@"ROW=%d",row);
            [retval setTextColor:[UIColor blueColor]];
         }
       if ([retval.text isEqualToString:@"Empresas, associações e outras entidades"]) {
            NSLog(@"ROW=%d",row);

            [retval setTextColor:[UIColor blueColor]];

       }


        [retval setBackgroundColor:[UIColor clearColor]];
        retval.font = [UIFont systemFontOfSize:14];

       }

    } else if(pickerView == horarioPicker) {
        retval.text =[arrayHorarios objectAtIndex:row];
        [retval setBackgroundColor:[UIColor clearColor]];
        retval.font = [UIFont systemFontOfSize:14];

    } else if(pickerView == examesPicker) {
        retval.text =[arrayExames objectAtIndex:row];
        [retval setBackgroundColor:[UIColor clearColor]];
        retval.font = [UIFont systemFontOfSize:14];

    } else if(pickerView == consultasPicker) {
        retval.text =[arrayConsultas objectAtIndex:row];
        [retval setBackgroundColor:[UIColor clearColor]];
        retval.font = [UIFont systemFontOfSize:14];

    }else {
        assert(NO);
    }
  return retval;
}

抱歉我的英语不好，我希望我能把问题说清楚，在此先感谢。

Answer 1

问题是，您正在为每一行重复使用 View ，并且您没有将 UILabel 颜色设置回黑色，因为它不应该是蓝色。

添加这段代码...

- (UIView *)pickerView:(UIPickerView *)pickerView viewForRow:(NSInteger)row forComponent:(NSInteger)component reusingView:(UIView *)view {
    UILabel *retval = (UILabel*)view;
    if (!retval) {
        retval= [[UILabel alloc] initWithFrame:CGRectMake(0.0f, 0.0f, [pickerView rowSizeForComponent:component].width, [pickerView rowSizeForComponent:component].height)];
    }
    [retval setTextColor:[UIColor blackColor]];
    retval.text = [arraySubSistemasDeSaude objectAtIndex:row];
    ......

有了这个，每次它拉出一个重复使用的 View 时，它都会首先将颜色设置为黑色。然后代码将检查您想要的蓝色并将它们设置为蓝色。你这样做的方式是，将其中一些设置为蓝色，然后当你重新使用它们时，你永远不会将其重置为黑色。