UIPickerView Tutorial

1. Add a New File, subclass of ViewController, to your project. In my example, the name of my class is ViewController.

2. Open ViewController.xib and drag a pickerview to your xib file.

 3. Add a UIPickerView IBOutlet to your ViewController.h file, and synthesize it to your ViewController.m.

@property (nonatomic, strong) IBOutlet UIPickerView *myPickerView; //.h

@synthesize myPickerView; //.m

4. Connect your IBOutlet property to the object in your .xib file.

5. Go back to your ViewController.h, and make your interface header look like this:

@interface ViewController : UIViewController<UIPickerViewDataSource, UIPickerViewDelegate> 

6. On your viewDidLoad, set the delegate and datasource of your pickerview to self;

- (void)viewDidLoad

{

    [super viewDidLoad];

    myPickerView.delegate = self;

    myPickerView.dataSource = self;

}

7. Add an array that will hold your items for you.

If your items are constant, use NSArray, else, use NSMutableArray.

@property (nonatomic, strong) NSArray *itemsArray; //.h

@ synthesize itemsArray; //.m

8. Initialize your array.

itemsArray = [[NSArray alloc] initWithObjects:@"Item 1", @"Item 2", @"Item 3", @"Item 4", @"Item 6", nil];

9. Add these delegate and datasource methods of pickerview in your ViewController.m class:

#pragma mark - UIPickerView DataSource

// returns the number of 'columns' to display.

- (NSInteger)numberOfComponentsInPickerView:(UIPickerView *)pickerView

{

    return 1;

}

// returns the # of rows in each component..

- (NSInteger)pickerView:(UIPickerView *)pickerView numberOfRowsInComponent:(NSInteger)component

{

    return [itemsArray count];

}

#pragma mark - UIPickerView Delegate

- (CGFloat)pickerView:(UIPickerView *)pickerView rowHeightForComponent:(NSInteger)component

{

    return 30.0;

}

- (NSString *)pickerView:(UIPickerView *)pickerView titleForRow:(NSInteger)row forComponent:(NSInteger)component

{

    return [itemsArray objectAtIndex:row];

}

//If the user chooses from the pickerview, it calls this function;

- (void)pickerView:(UIPickerView *)pickerView didSelectRow:(NSInteger)row inComponent:(NSInteger)component

{

    //Let's print in the console what the user had chosen;

    NSLog(@"Chosen item: %@", [itemsArray objectAtIndex:row]);

}

10. Done! Hit Run!