在选取器视图中未选择第一个值

Question

你好 我在单击一个按钮选择器视图时有一些按钮，但如果滚动则不会选择第一个值，然后只选择第一个值，所以请帮助我，

这是我的代码，

- (void)pickerView:(UIPickerView *)thePickerView didSelectRow:(NSInteger)row inComponent:(NSInteger)component {



    switch (tagVlaue) {

    case 0:
    { 
        if(gender==YES)
       {

           NSLog(@"Selected Color: %@. Index of selected color: %i", [checkArray objectAtIndex:row], row);

           selectedgender=[checkArray objectAtIndex:row];
           NSLog(@"selected checkgender %@",selectedgender);
           genderlabel.text=selectedgender;
          // checkgender=NO;
       }
     else 
         {

             NSLog(@"Selected Color: %@. Index of selected color: %i", [genderArray objectAtIndex:row], row);

             selectedgender=[genderArray objectAtIndex:row];
             NSLog(@"selected gender %@",selectedgender);
             genderlabel.text=selectedgender;
            // checkgender=YES; 


        }
        //genderlabel
    }
        break;
    case 1:
    {
        if(gender==NO)
        {
        NSLog(@"Selected Color: %@. Index of selected color: %i", [seekingArray objectAtIndex:row], row);   
        selectedseek=[seekingArray objectAtIndex:row];
        NSLog(@"selected seeking %@",selectedseek);
        seeklabel.text=selectedseek;
        }
        else {
            NSLog(@"Selected Color: %@. Index of selected color: %i", [seekCheckArray objectAtIndex:row], row); 
            selectedseek=[seekCheckArray objectAtIndex:row];
            NSLog(@"selected seeking %@",selectedseek);
            seeklabel.text=selectedseek;
        }

    }
        break;

    case 2:
        NSLog(@"Selected Color: %@. Index of selected color: %i", [ageArray objectAtIndex:row], row);

        selectedage=[ageArray objectAtIndex:row];
        NSLog(@"selected age %@",selectedage);
        label.text=selectedage;


        break;
    case 3:
        NSLog(@"Selected Color: %@. Index of selected color: %i", [feetArray objectAtIndex:row], row);  
        selectedheight=[feetArray objectAtIndex:row];
        NSLog(@"selected height %@",selectedheight);
        heightlabel.text=selectedheight;


        break;

    case 4:

        NSLog(@"Selected Color: %@. Index of selected color: %i", [weightArray objectAtIndex:row], row);    
        selectedweight=[weightArray objectAtIndex:row];
        NSLog(@"selected weight %@",selectedweight);
        weightlabel.text=selectedweight;

        break;

    case 5:
        NSLog(@"Selected Color: %@. Index of selected color: %i", [enthnicityArray objectAtIndex:row],row);


        selectedethnicity=[enthnicityArray objectAtIndex:row];
        NSLog(@"selected weight %@",selectedethnicity);
        ethnicitylabel.text=selectedethnicity;

        break;

    case 6:
        NSLog(@"Selected Color: %@. Index of selected color: %i", [typeArray objectAtIndex:row],row);


        selectedtype=[typeArray objectAtIndex:row];
        NSLog(@"selected weight %@",selectedtype);
        typelabel.text=selectedtype;

        break;


    default:
        break;
}

谢谢您的提前

Answer 1

委托方法：

- (void)pickerView:(UIPickerView *)pickerView didSelectRow:(NSInteger)row inComponent:(NSInteger)component;

仅当用户在选择器中显式选择值时调用。您必须获取自己首次显示选择器时在选择器中选择的值。例如，您可以查看选择器数据源。

Answer 2

使用 UIPickerViewDelegate – pickerView:didSelectRow:inComponent: 的委托方法来了解哪一行已被选择，如果用户没有选择任何内容，则不会调用该方法。