Choice

In plain words

A question with several possible answers, each one a button.

A message with your own buttons: options are (label, on_press) pairs and the last one is the main one.

ui.choice · Category: Dialogs · Full reference →

Preview

Code

ui.dialog_layer(main_view(), ui.choice(
    "notes.py already exists in this folder.",
    [("Keep both", on_keep), ("Skip", on_skip), ("Replace", on_replace)],
    on_cancel, title="File exists", width=420,
))

New

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When to use

• When a question has more than two answers (Keep both / Replace / Skip).

Usage

from pyzed import ui

ui.dialog_layer(main_view(), ui.choice(
    "notes.py already exists in this folder.",
    [("Keep both", on_keep), ("Skip", on_skip), ("Replace", on_replace)],
    on_cancel, title="File exists", width=420,
))

Variants

About these captures

Each capture is recorded by pyzed itself, off-screen at 2x, in One Dark or One Light to match this site’s theme, and cropped to the component so it shows at its real size. The pointer hovers, presses or types into it; a component that does not react to the pointer cycles through a few themes. With reduced motion you see the first frame. Open Code under a capture to see the snippet that draws it; free names such as on_save stand for your own callbacks.

Options

Two answers

Code

ui.choice("Open the project in…", [("This window", on_here), ("New window", on_new)],
          on_cancel, width=360)

Three answers

Code

ui.choice("notes.py already exists.", [("Keep both", on_keep), ("Skip", on_skip),
          ("Replace", on_replace)], on_cancel, title="File exists", width=400)

Events

Choice has 1 event of its own, listed below. Like every widget it also has the 18 common events (click, double_click, right_click, mouse_enter, drag, key_down, resize…), attached with .on(...): see Events and Events of every component.

Event	Handler gets	When
on_cancel	()	The close icon.

Handler gets is what Pyzed passes to your callable: () means nothing. Any handler can also be a message (a value that is not callable), which goes to update().

Handling the events

The same events written three ways. Imperative: methods of the app change self. Declarative: the handlers produce messages and one update() decides. Functional: a pure function draws an immutable state and asks for changes with set_state(...). See Imperative, declarative and functional.

Imperative

class Copy(pz.App):
    def __init__(self):
        self.asking, self.answer = True, None

    def answer_with(self, what):
        self.asking, self.answer = False, what

    def view(self):
        dialog = ui.choice("notes.py already exists in this folder.",
                           [("Keep both", lambda: self.answer_with("both")),   # one handler per option
                            ("Replace", lambda: self.answer_with("replace"))],
                           lambda: setattr(self, "asking", False),             # on_cancel: the ✕
                           title="File exists")
        return ui.dialog_layer(main_view(), dialog if self.asking else None)

Declarative

from dataclasses import dataclass


@dataclass
class Answer:
    what: str


class Copy(pz.App):
    asking = True

    def update(self, message):
        match message:
            case Answer(what):
                self.asking = False
                print("chose", what)
            case "cancel":
                self.asking = False

    def view(self):
        dialog = ui.choice("notes.py already exists.", [("Keep both", Answer("both")),
                                                        ("Replace", Answer("replace"))], "cancel")
        return ui.dialog_layer(main_view(), dialog if self.asking else None)

Functional

from dataclasses import dataclass


@dataclass(frozen=True)
class State:
    answer: str = ""


def view(state, set_state):
    if state.answer:
        return ui.label(f"You chose: {state.answer}")
    return ui.dialog_layer(main_view(), ui.choice(
        "notes.py already exists.",
        [(label, lambda a=answer: set_state(answer=a)) for label, answer in (("Keep both", "both"),
                                                                            ("Replace", "replace"))],
        lambda: set_state(answer="cancel")))

Properties and API

ui.choice

choice(message, options, on_cancel, *, title=None, width=440, theme=None)

A message with your own buttons.

Property	Default	Description
message	required	Any Python value, or a callable.
options	required	(label, on_press) pairs; the last one is the main button.
title	None	Title.
width	440	Width: pixels, "fill", "shrink" or "fill:N" (proportion).
theme	None	Theme to use instead of the current one (pyzed.theme.current()).

Events: on_cancel (events).

Full reference →

Related

ConfirmA yes/no question, red for destructive actions.

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