UIPickerView在ios 7.1模拟器中重新加载时丢失数据

Question

我在UIPickerView中遇到问题。我正在尝试根据以下方法创建UIImageView

- (UIView *)pickerView:(UIPickerView *)pickerView viewForRow:(NSInteger)row forComponent:(NSInteger)component reusingView:(UIView *)view

在上面的方法中我放了一个条件.i.e if(view == nil)但是它总是返回视图为nil，它不会进入else条件。

代码是

- (UIView *)pickerView:(UIPickerView *)pickerView viewForRow:(NSInteger)row forComponent:(NSInteger)component reusingView:(UIView *)view
{
if(view == nil)
{
    UIView *rowView;
        rowView = [[[UIView alloc] initWithFrame:CGRectMake(0, 0, 1024, 22)] retain];
        [rowView setBackgroundColor:[UIColor clearColor]];

        UIImageView *checkOrUncheck = [[UIImageView alloc] initWithFrame:CGRectMake(40, 1, 18, 18)];
        [checkOrUncheck setImage:nil];
        [checkOrUncheck setTag:-100];

        UIButton *rowLabel = [UIButton buttonWithType:UIButtonTypeCustom];
        rowLabel.frame = CGRectMake(70, 1, 904, 20);
        [rowLabel setBackgroundColor:[UIColor clearColor]];
        [rowLabel setTitleColor:[UIColor blackColor] forState:UIControlStateNormal];
        [rowLabel.titleLabel setFont:[UIFont fontWithName:@"Helvetica-Bold" size:22]];
        rowLabel.contentHorizontalAlignment = UIControlContentHorizontalAlignmentLeft;
        [rowLabel setTag:-101];

        if([pickerView isEqual:returnDatePicker])
        {
            [rowLabel setTitle:[returnDatesDurationArray objectAtIndex:row] forState:UIControlStateNormal];
        }
        else if([pickerView isEqual:selectProductPicker])
        {
            NSMutableDictionary *dict = [selectProductsArray objectAtIndex:row];
            [rowLabel setTitle:[dict objectForKey:@"Name"] forState:UIControlStateNormal];
        }

        [rowView addSubview:checkOrUncheck];
        [rowView addSubview:rowLabel];
    }
else
{
        NSLog(@"no");
}
    return rowView;
}

请告诉我代码中的错误。感谢您花时间留言。