How do I reload/refresh the UIPickerView (with new data array) based on button press?

Question

IF I wanted a picker, for states/provinces, i haven't seen an example, but I mocked up shown above, a picker for US/Can/Mex. wondering can you dynamically switch the NSMutableArray for the UIPickerView and then have it somehow reload each time you click on US/Can/Mex buttons??? How do I go about doing this. What approach do I take. Looking for someone to point a beginner for a clue in the right direction.

vikingosegundo · Accepted Answer · 2011-12-22T01:16:46.410

You will have to implement the datasource and the delegate.

once you press a button, set an array pointer to the appropriate array.

than call [thePicker reloadAllComponents];

-(IBAction) usButtonPressed:(id)sender{
    self.inputArray = self.usArray;
    [self.thePicker reloadAllComponents];
}

-(IBAction) mexicoButtonPressed:(id)sender{
    self.inputArray = self.mexicoArray;
    [self.thePicker reloadAllComponents];
}

the datasource methods:

- (NSInteger)numberOfComponentsInPickerView:(UIPickerView *)pickerView
{
    return 1;
}


- (NSInteger)pickerView:(UIPickerView *)pickerView numberOfRowsInComponent:(NSInteger)component
{
    return [self.inputArray count];
}

the delegate methods:

- (NSString *)pickerView:(UIPickerView *)pickerView titleForRow:(NSInteger)row forComponent:(NSInteger)component
{
    return [self.inputArray objectAtIndex:row];
}

Thanks for pointing me in the right direction. I'm a newbie. Ok great to see there's a class method for it. and that it "Calling this method causes the picker view to query the delegate for new data for all components" very cool. My current UI Picker has the datasource and delegate methods :-) so thats good. I'm usinga a book, didn't know the answer was right in the instance methods of the Class documentation. Thanks again. — jim4iOS, Dec 22 '11 at 05:32

score 30 · Answer 2 · edited May 14 '20 at 12:09

30

Swift: xcode 6.1

// reload the component of picker (Used this inside the trigger action or button)

[self.pickerControl reloadAllComponents];

edited May 14 '20 at 12:09

Naresh

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answered Nov 12 '14 at 07:19

Vinod Joshi

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this does not answer the question at all. – vikingosegundo Sep 25 '15 at 18:32
Well, it is the perfect answer that I was looking for. Up vote! – Doug Null Aug 29 '22 at 22:30

Enamul Haque · Answer 3 · 2019-12-28T12:23:15.437

9

In swift 3,4,or 5 you just write in didSelectRow function like bellow

func pickerView(_ pickerView: UIPickerView, didSelectRow row: Int, inComponent component: Int) {


        self.view.endEditing(false)
        yourPickerView.selectRow(0, inComponent: 0, animated: true)
        yourPickerView.reloadAllComponents();

}

edited Dec 28 '19 at 12:23

answered Oct 02 '17 at 06:03

Enamul Haque

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score 7 · Answer 4 · answered Jun 23 '16 at 16:45

7

By calling

thePicker.delegate = self;

again, I was able to force refresh the pickerview with new info

answered Jun 23 '16 at 16:45

Juan Manuel

239
2
4

score 2 · Answer 5 · answered May 12 '17 at 08:34

2

In your button press action,

[self.pickerView selectRow:0 inComponent:0 animated:YES];

answered May 12 '17 at 08:34

Jeff John

31
3

score 2 · Answer 6 · answered Dec 22 '11 at 01:12

2

Use multiple pickers, or use a switch block to determine which data should be loaded, and reload the picker.

answered Dec 22 '11 at 01:12

WrightsCS

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How do I reload/refresh the UIPickerView (with new data array) based on button press?

6 Answers6

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