2 つのコンポーネントの代わりに、次のスニペットのように 4 つのコンポーネントを作成してみてください。
- (void)viewDidLoad
{
[super viewDidLoad];
self.model = @[@"1",@"2",@"3",@"4",@"5",@"6"];
}
- (NSInteger)numberOfComponentsInPickerView:(UIPickerView *)pickerView
{
return 4;
}
- (NSInteger)pickerView:(UIPickerView *)pickerView numberOfRowsInComponent:(NSInteger)component
{
NSInteger numberOfRows;
if(component == 0 || component == 2)
{
numberOfRows = [self.model count];
}
else
{
numberOfRows = 1;
}
return numberOfRows;
}
- (NSString *)pickerView:(UIPickerView *)pickerView titleForRow:(NSInteger)row forComponent:(NSInteger)component
{
NSString* title;
switch (component) {
case 0:
case 2:
title = self.model[row];
break;
case 1:
title = @"ft";
break;
case 3:
title = @"in";
break;
default:
break;
}
return title;
}