The app is freezing whe开发者_如何学Gon the array is being loaded.
Getting Error at NSString *weight line:
*** Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: '-[NSCFString stringValue]: unrecognized selector sent to instance 0x14904'
Here is my code:
- (IBAction)weightButtonPressed
{
pickerArrayHalf = [[NSMutableArray alloc]initWithCapacity:2];
[pickerArrayHalf addObject:@"0"];
[pickerArrayHalf addObject:@"1/2"];
}
- (UIView *)pickerView:(UIPickerView *)pickerView viewForRow:(NSInteger)row forComponent:(NSInteger)component reusingView:(UIView *)view
{
UILabel *label = [[UILabel alloc] initWithFrame:CGRectMake(0, 0, 300, 37)];
NSString *weight = [[pickerArrayHalf objectAtIndex:row] stringValue];
label.text = [NSString stringWithFormat:@"%@", weight];
}
You stored NSString
s in the array using @"0"
and @"1/2"
and NSString
does not respond to stringValue, it is a string. Just remove stringValue from the method calls.
NSString *weight = [pickerArrayHalf objectAtIndex:row];
Side Note:
You are over complicating setting the text of the label. Simply do the following.
label.text = [pickerArrayHalf objectAtIndex:row];
Also you are not retuning any view in that example which should generate a warning. The last line should be
//I would recommend calling autorelease on the initial alloc/initWithFrame
return [label autorelease];
You're adding a string to the array:
[pickerArrayHalf addObject:@"0"];
so there's no use to later on asking the string for its stringValue:
[[pickerArrayHalf objectAtIndex:row] stringValue];
Get rid of the call to stringValue
(NSString does not even implement stringValue, for obvious reasons):
NSString *weight = [pickerArrayHalf objectAtIndex:row];
Further more why are you wrapping your string into a new one here?:
label.text = [NSString stringWithFormat:@"%@", weight];
just do this:
NSString *weight = [pickerArrayHalf objectAtIndex:row];
label.text = weight;
or even shorter:
label.text = [pickerArrayHalf objectAtIndex:row];
Last but not least your pickerView :…
method is leaking label
and not returning a UIView as expected.
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