iPhone SDK: NSInvalidArgumentException -UIView numberOfComponentsInPickerView

Question

I am trying to develop a simple search mechanism on a UIPicker. The approach I am using is to keep two arrays. My problem is that for some reason I am getting this run-time error.

*** Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: '*** -[UIView numberOfComponentsInPickerView:]

Here are the array declarations.

//data source for UIPicker NSArray
*arrayCountryChoices;

//search results buffer 
NSMutableArray *arraySearchResults; 

//properties
@property(nonatomic,retain) NSArray*arrayCountryChoices; 
@property(nonatomic,retain) NSMutableArray *arraySearchResults;

Here is where I initialize the data

//create data
  arrayCountryChoices = [NSArray arrayWithObjects:@"foo",@"bar",@"baz",nil];

//copy the original array to searchable array
arraySearchResults = [arrayCountryChoices mutableCopy];

An the picker methods.

- (NSInteger)numberOfComponentsInPickerView:(UIPickerView *)thePickerView {
return 1;
}
- (NSInteger)pickerView:(UIPickerView *)thePickerView numberOfRowsInComponent:(NSInteger)component {
return [arraySearchResults count];
}
- (NSString *)pickerView:(UIPickerView *)thePickerView titleForRow:(NSInteger)row forComponent:(NSInteger)component {
return [arraySearchResults objectAtIndex:row];
}
- (void)pickerView:(UIPickerView *)thePickerView didSelectRow:(NSInteger)row inComponent:(NSInteger)component {
//grab the selected country
strUserChoice = [arraySearchResults objectAtIndex:row];
}

Here is the search code for completeness although not really relevant yet as the app dies before we ever get here.

//filter on search term
NSPredicate* predicate = [NSPredicate predicateWithFormat:@"SELF beginswith[c] %@", strSearchText];
[arraySearchResults filterUsingPredicate: predicate];
[pickerCountry reloadComponent:0];

I have also dragged datasource and delegate connections from the UIPicker to Files Owner in Interface Builder. Any ideas? Thanks in advance.

Answer 1

Looks like you've got the picker's data source set to something other than the object that implements the code you've posted there—apparently a UIView somewhere. Make sure the picker's outlets point to your actual data-source object.