让UIPicker至少有一英尺的价值？

Just like with Apples timer app, you can't select "0". You have to choose at least 1 hour or 1 minute. Here is how I'm formatting the textfield for the picker..

就像Apples计时器应用程序一样,您不能选择“0”。你必须选择至少1小时或1分钟。这是我如何格式化选择器的文本字段..

//Formats the textfield based on the pickers.
- (void)pickerView:(UIPickerView *)pickerView didSelectRow:(NSInteger)row inComponent:(NSInteger)component {

NSString *result = [feetArray objectAtIndex:[feetPicker selectedRowInComponent:0]];

result = [result stringByAppendingFormat:@"%@ft", [feetArray objectAtIndex:[feetPicker selectedRowInComponent:1]]];
result = [result stringByAppendingFormat:@" %@", [inchArray objectAtIndex:[inchesPicker selectedRowInComponent:0]]];
result = [result stringByAppendingFormat:@"%@", [inchArray objectAtIndex:[inchesPicker selectedRowInComponent:1]]];
result = [result stringByAppendingFormat:@" %@in", [fractionArray objectAtIndex:[fractionPicker selectedRowInComponent:0]]];

RiseTextField.text = result;
}

What I need to if they choose "0" all the way across, I want the foot to automatically go to 1 on the picker. I have 3 pickers in my view made as one. 2 components for feet, 2 components for inches then 1 component for fractions. so its displayed in the textfield like 10f 09 1/16in.

如果他们一直选择“0”我需要什么,我希望脚在选择器上自动转到1。在我看来,我有3个采摘者。 2个组件用于英尺,2个组件用于英寸,然后1个组件用于分数。因此它在文本字段中显示为10f 09 1 / 16in。

1 个解决方案

#1

Essentially what you want to do is this:(assuming that row 0 contains the zero values)

基本上你想要做的是:(假设第0行包含零值)

-(void)pickerView:(UIPickerView *)pickerView didSelectRow:(NSInteger)row inComponent:(NSInteger)component{
    if (([feetPicker selectedRowInComponent:0] == 0)&&
        ([feetPicker selectedRowInComponent:1] == 0)&&
        ([inchesPicker selectedRowInComponent:0] == 0)&&
        ([inchesPicker selectedRowInComponent:1] == 0)&&
        ([fractionPicker selectedRowInComponent:0] == 0)){
        // All values zero
        [feetPicker selectRow:1 
                  inComponent:1 
                     animated:YES];
        return;
    }
    // Handle valid value
}

On a side note consider using an NSMutableString for result. Then instead of creating a new NSString every line you can just call [result appendFormat:@".... to modify the one you have.

另外,请注意使用NSMutableString作为结果。然后,不是每行创建一个新的NSString,你可以调用[result appendFormat:@“....来修改你拥有的那个。

#1