Two uipicker in the same view - iphone

Question

what i am trying to do is to put two uipickers on the same view, i read somewhere that one of them should have its own separate delegate i tried to do so but i couldn't make it work properly.
Some times when i run the application the second application just stops working with no errors on the console.
this is the .h file for the view:
#interface FirstViewController : UIViewController {
IBOutlet UIPickerView *cities;
NSMutableArray *array;
NSString *picked;
}
#property(nonatomic,retain) IBOutlet UIPickerView *cities;
#property(nonatomic,retain) IBOutlet NSMutableArray *array;
and here is the .m:
#implementation FirstViewController
#synthesize cities,array;
-(void) getCities:(NSString *)link{
url=link;
NSString *str=[[NSString alloc] initWithContentsOfURL:[NSURL URLWithString:url]];
if([str length]==0){
[str release];
return;
}
SBJsonParser *parser=[[SBJsonParser alloc] init];
array=[[parser objectWithString:str] copy];
[receivedData release];
}
- (NSInteger)numberOfComponentsInPickerView:(UIPickerView *)thePickerView { // This method needs to be used. It asks how many columns will be used in the UIPickerView
return 1; // We only need one column so we will return 1.
}
- (NSInteger)pickerView:(UIPickerView *)thePickerView numberOfRowsInComponent:(NSInteger)component { // This method also needs to be used. This asks how many rows the UIPickerView will have.
return [array count]; // We will need the amount of rows that we used in the pickerViewArray, so we will return the count of the array.
}
- (void)pickerView:(UIPickerView *)thePickerView didSelectRow:(NSInteger)row inComponent:(NSInteger)component { // what happens when selecting rows
picked=[array objectAtIndex:row];
}
- (NSString *)pickerView:(UIPickerView *)thePickerView titleForRow:(NSInteger)row forComponent:(NSInteger)component { //method asks for what the title or label of each row will be
return [array objectAtIndex:row]; // We will set a new row for every string used in the array.
}
// Implement viewDidLoad to do additional setup after loading the view, typically from a nib.
- (void)viewDidLoad
{
[sv setScrollEnabled:TRUE];
[sv setContentSize:CGSizeMake(320, 800)];
[self getCities:#"any url"];
[super viewDidLoad];
}
- (BOOL)shouldAutorotateToInterfaceOrientation:(UIInterfaceOrientation)interfaceOrientation
{
// Return YES for supported orientations
return (interfaceOrientation == UIInterfaceOrientationPortrait);
}
- (void)didReceiveMemoryWarning
{
// Releases the view if it doesn't have a superview.
[super didReceiveMemoryWarning];
// Release any cached data, images, etc. that aren't in use.
}
- (void)viewDidUnload
{
[super viewDidUnload];
// Release any retained subviews of the main view.
// e.g. self.myOutlet = nil;
}
- (void)dealloc
{
[super dealloc];
}
#end
and for the second uipicker i added an nsobject to the view and changed its class to "SecondPickerDelegate" which i created before and this is its code:
.h
#import <UIKit/UIKit.h>
#interface FirstViewSecondPickerDelegate : UIViewController<UIPickerViewDelegate>{
IBOutlet UIPickerView *specialities;
NSMutableArray *array;
NSString *picked;
}
#property(nonatomic,retain) IBOutlet UIPickerView *specialities;
#property(nonatomic,retain) NSMutableArray *array;
#property(nonatomic,retain) NSString *picker;
#end
the .m file:
#import "FirstViewSecondPickerDelegate.h"
#import "JSON.h"
#implementation FirstViewSecondPickerDelegate
#synthesize specialities,array,picker;
-(void) getSpecialities:(NSString *)link{
url=link;
NSString *str=[[NSString alloc] initWithContentsOfURL:[NSURL URLWithString:url]];
if([str length]==0){
[str release];
return;
}
SBJsonParser *parser=[[SBJsonParser alloc] init];
array=[[parser objectWithString:str] copy];
for(int i=0;i<[array count];i++){
NSLog(#"index %i",i);
NSLog(#"value %#",[array objectAtIndex:i]);
}
}
- (NSInteger)numberOfComponentsInPickerView:(UIPickerView *)thePickerView { // This method needs to be used. It asks how many columns will be used in the UIPickerView
return 1; // We only need one column so we will return 1.
}
- (NSInteger)pickerView:(UIPickerView *)thePickerView numberOfRowsInComponent:(NSInteger)component { // This method also needs to be used. This asks how many rows the UIPickerView will have.
return [array count]; // We will need the amount of rows that we used in the pickerViewArray, so we will return the count of the array.
}
- (void)pickerView:(UIPickerView *)thePickerView didSelectRow:(NSInteger)row inComponent:(NSInteger)component { // what happens when selecting rows
picked=[array objectAtIndex:row];
}
- (NSString *)pickerView:(UIPickerView *)thePickerView titleForRow:(NSInteger)row forComponent:(NSInteger)component { //method asks for what the title or label of each row will be
return [array objectAtIndex:row]; // We will set a new row for every string used in the array.
}
- (id)initWithNibName:(NSString *)nibNameOrNil bundle:(NSBundle *)nibBundleOrNil
{
self = [super initWithNibName:nibNameOrNil bundle:nibBundleOrNil];
if (self) {
// Custom initialization
picked=#"1";
[self getSpecialities:#"http://localhost:8080/Test/gs"];
}
return self;
}
/*
-(void) viewDidLoad{
[super viewDidLoad];
}
*/
- (void)dealloc
{
[super dealloc];
}
- (void)didReceiveMemoryWarning
{
// Releases the view if it doesn't have a superview.
[super didReceiveMemoryWarning];
// Release any cached data, images, etc that aren't in use.
}
#pragma mark - View lifecycle
/*
// Implement loadView to create a view hierarchy programmatically, without using a nib.
- (void)loadView
{
}
*/
// Implement viewDidLoad to do additional setup after loading the view, typically from a nib.
- (void)viewDidLoad
{
[super viewDidLoad];
}
- (void)viewDidUnload
{
[super viewDidUnload];
// Release any retained subviews of the main view.
// e.g. self.myOutlet = nil;
}
- (BOOL)shouldAutorotateToInterfaceOrientation:(UIInterfaceOrientation)interfaceOrientation
{
// Return YES for supported orientations
return (interfaceOrientation == UIInterfaceOrientationPortrait);
}
#end
If any one has a working example for such case please help.

Answer 1

You don't need separate delegates for two UIPickerView's in the same view.
Use the UIPickerView tag property, and then you can differentiate between them in delegate methods.