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Has there been any thought to adding a picker wheel like the DatePicker but for any list of data?

It's "rarely" used component in the iOS world (IMO), maybe that's the reason why it's not in the ui module. Or it wasn't just on top of the list. Anyway, you can write your own with objc_util & UIPickerView.

@bogfard I had already tried but I've never understood why when the wheel rolls too far, data disappear.
Thus, I've stopped to spend time, but you can try this script

@cvp here's working one ...

# coding: utf-8

from objc_util import ObjCInstance, c, ObjCClass, ns, create_objc_class, NSObject
from ctypes import c_void_p
import ui


# Data for both pickers
_data = [
    [str(x) for x in range(2000, 2040)],
    ['xxxx', 'yyyy', 'zzzz']
]

# ObjC classes
UIColor = ObjCClass('UIColor')
UIPickerView = ObjCClass('UIPickerView')
UIFont = ObjCClass('UIFont')
NSAttributedString = ObjCClass('NSAttributedString')


# Default attributes, no need to recreate them again and again
def _str_symbol(name):
    return ObjCInstance(c_void_p.in_dll(c, name))


_default_attributes = {
    _str_symbol('NSFontAttributeName'): UIFont.fontWithName_size_(ns('Courier'), 16),
    _str_symbol('NSForegroundColorAttributeName'): UIColor.redColor(),
    _str_symbol('NSBackgroundColorAttributeName'): UIColor.greenColor()
}


# Data source & delegate methods
def pickerView_attributedTitleForRow_forComponent_(self, cmd, picker_view, row, component):
    tag = ObjCInstance(picker_view).tag()
    return NSAttributedString.alloc().initWithString_attributes_(ns(_data[tag - 1][row]), ns(_default_attributes)).ptr


def pickerView_titleForRow_forComponent_(self, cmd, picker_view, row, component):
    tag = ObjCInstance(picker_view).tag()
    return ns(_data[tag - 1][row]).ptr


def pickerView_numberOfRowsInComponent_(self, cmd, picker_view, component):
    tag = ObjCInstance(picker_view).tag()
    return len(_data[tag - 1])


def numberOfComponentsInPickerView_(self, cmd, picker_view):
    return 1


def rowSize_forComponent_(self, cmd, picker_view, component):
    return 100


def pickerView_rowHeightForComponent_(self, cmd, picker_view, component):
    return 30


def pickerView_didSelectRow_inComponent_(self, cmd, picker_view, row, component):
    tag = ObjCInstance(picker_view).tag()
    print(f'Did select {_data[tag - 1][row]}')


methods = [
    numberOfComponentsInPickerView_, pickerView_numberOfRowsInComponent_,
    rowSize_forComponent_, pickerView_rowHeightForComponent_, pickerView_attributedTitleForRow_forComponent_,
    pickerView_didSelectRow_inComponent_
]

protocols = ['UIPickerViewDataSource', 'UIPickerViewDelegate']


UIPickerViewDataSourceAndDelegate = create_objc_class(
    'UIPickerViewDataSourceAndDelegate', NSObject, methods=methods, protocols=protocols
)


# UIPickerView wrapper which behaves like ui.View (in terms of init, layout, ...)
class UIPickerViewWrapper(ui.View):
    def __init__(self, **kwargs):
        super().__init__(**kwargs)
        self._picker_view = UIPickerView.alloc().initWithFrame_(ObjCInstance(self).bounds()).autorelease()
        ObjCInstance(self).addSubview_(self._picker_view)

    def layout(self):
        self._picker_view.frame = ObjCInstance(self).bounds()

    @property
    def tag(self):
        return self._picker_view.tag()

    @tag.setter
    def tag(self, x):
        self._picker_view.setTag_(x)

    @property
    def delegate(self):
        return self._picker_view.delegate()

    @delegate.setter
    def delegate(self, x):
        self._picker_view.setDelegate_(x)

    @property
    def data_source(self):
        return self._picker_view.dataSource()

    @data_source.setter
    def data_source(self, x):
        self._picker_view.setDataSource_(x)


class MyView(ui.View):
    def __init__(self, **kwargs):
        super().__init__(**kwargs)

        self.background_color = 'white'

        self.delegate_and_datasource = UIPickerViewDataSourceAndDelegate.alloc().init().autorelease()

        pv1 = UIPickerViewWrapper(frame=[100, 100, 200, 100])
        pv1.delegate = self.delegate_and_datasource
        pv1.data_source = self.delegate_and_datasource
        pv1.tag = 1
        self.add_subview(pv1)

        pv2 = UIPickerViewWrapper(frame=[100, 400, 200, 100])
        pv2.delegate = self.delegate_and_datasource
        pv2.data_source = self.delegate_and_datasource
        pv2.tag = 2
        self.add_subview(pv2)


if __name__ == '__main__':
    v = MyView()
    v.present('full_screen')

@zrzka One more time, thanks a lot...
I'm not sure I'll try to write my-self some Objective-C code in the future.
Could you, in some words, tell me why my code was erroneous.

@zrzka

I am working on a lib of lesser used UI components as well as components I create for my own projects (ie Modal box, web style drop down)

Are you okay if I include your code - with it?

I had intentions of doing it, but since you already have it working pretty well, its a big time saver especially since I don't do objc that well.

Once the module is somewhat stable i will be open sourcing it as MIT and posting here.

I will of course keep any copyright text you deem fit.

@reticulated feel free, it's just a snippet. Whatever I put on the forum I consider public domain. Also it's @cvp code, I just modified it a bit.

@cvp honestly I don't know. I just pasted it to Pythonista, rewrite non pythonic parts, ... and it worked :)

@zrzka Anyway, once more, thanks for your time.

@reticulated

How is the lib coming? I would love to get that!