Thread history

In plain words

The list of your earlier chats, sorted by day, with a box to search them.

ui.ThreadHistory is a component for past conversations: a search box and the threads grouped by when they were last updated (Today, Yesterday, This week, This month, Older). Each row shows the title, an optional detail (the model or the agent) and a delete button. threads are dicts or objects with id, title, updated (a time.time() timestamp) and detail; selected marks the open one. Picking a thread reports on_open and the trash button on_delete, both with the thread’s id in event.value. The component keeps the search text itself.

ui.ThreadHistory · Category: AI agents · Full reference →

Preview

Code

import time

now = time.time()
pz.container(ui.ThreadHistory(threads=[
    {"id": "1", "title": "Add a login form", "updated": now - 60, "detail": "Claude"},
    {"id": "2", "title": "Fix the failing tests", "updated": now - 900, "detail": "Claude"},
    {"id": "3", "title": "Dark theme for the settings", "updated": now - 86400, "detail": "Gemini CLI"},
    {"id": "4", "title": "Export the table to CSV", "updated": now - 4 * 86400},
    {"id": "5", "title": "First steps", "updated": now - 60 * 86400},
], selected="1", on_open=on_open, on_delete=on_delete), width=380, height=320)

New

This component was added recently. Tell us how it works for you in the issue tracker.

When to use

• In a side panel or a popover of a chat app, to reopen an earlier conversation.

Usage

import pyzed as pz
from pyzed import ui

class Chats(pz.App):
    def __init__(self):
        self.threads = load_threads()  # [{"id", "title", "updated", "detail"}, ...]
        self.open_id = ""

    def delete(self, ident):
        self.threads = [t for t in self.threads if t["id"] != ident]

    def view(self):
        return ui.ThreadHistory(threads=self.threads, selected=self.open_id,
                                on_open=lambda e: setattr(self, "open_id", e.value),
                                on_delete=lambda e: self.delete(e.value))

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.

State

The search ones are drawn with text typed in the box (the component keeps it).

Grouped by day

Code

import time

now = time.time()
threads = [
    {"id": "1", "title": "Add a login form", "updated": now - 60, "detail": "Claude"},
    {"id": "2", "title": "Fix the failing tests", "updated": now - 86400},
    {"id": "3", "title": "Export the table to CSV", "updated": now - 4 * 86400},
]
pz.container(ui.ThreadHistory(threads=threads), width=320, height=260)

selected="2"

Code

import time

now = time.time()
threads = [
    {"id": "1", "title": "Add a login form", "updated": now - 60, "detail": "Claude"},
    {"id": "2", "title": "Fix the failing tests", "updated": now - 86400},
    {"id": "3", "title": "Export the table to CSV", "updated": now - 4 * 86400},
]
pz.container(ui.ThreadHistory(threads=threads, selected="2"), width=320, height=260)

No threads

Code

pz.container(ui.ThreadHistory(threads=[]), width=320, height=110)

Searching

Code

import time

now = time.time()
threads = [
    {"id": "1", "title": "Add a login form", "updated": now - 60, "detail": "Claude"},
    {"id": "2", "title": "Fix the failing tests", "updated": now - 86400},
    {"id": "3", "title": "Export the table to CSV", "updated": now - 4 * 86400},
]
pz.container(ui.ThreadHistory(threads=threads), width=320, height=160)

Nothing matches

Code

import time

now = time.time()
threads = [
    {"id": "1", "title": "Add a login form", "updated": now - 60, "detail": "Claude"},
    {"id": "2", "title": "Fix the failing tests", "updated": now - 86400},
    {"id": "3", "title": "Export the table to CSV", "updated": now - 4 * 86400},
]
pz.container(ui.ThreadHistory(threads=threads), width=320, height=110)

Events

Thread history has 2 events 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.

It is a pz.Component, so it also raises on_mount and on_unmount, and its handlers get a pz.Event whose value holds the data.

Event	Handler gets	When
on_open	(event)	A thread was picked (event.value is its id).
on_delete	(event)	Delete was pressed on a thread.

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

import time


class Chats(pz.App):
    def __init__(self):
        now = time.time()
        self.threads = [{"id": "1", "title": "Add a login form", "updated": now - 60},
                        {"id": "2", "title": "Fix the tests", "updated": now - 900}]
        self.open_id = "1"

    def view(self):                      # event.value is the thread's id
        return ui.ThreadHistory(threads=self.threads, selected=self.open_id,
                                on_open=lambda e: setattr(self, "open_id", e.value),
                                on_delete=lambda e: self.delete(e.value))

    def delete(self, ident):
        self.threads = [t for t in self.threads if t["id"] != ident]

Declarative

from dataclasses import dataclass


@dataclass
class OpenThread:
    ident: str


@dataclass
class DeleteThread:
    ident: str


class Chats(pz.App):
    threads = [{"id": "1", "title": "Add a login form", "updated": 0}]
    open_id = ""

    def update(self, message):
        match message:
            case OpenThread(ident):
                self.open_id = ident
            case DeleteThread(ident):
                self.threads = [t for t in self.threads if t["id"] != ident]

    def view(self):
        return ui.ThreadHistory(threads=self.threads, selected=self.open_id,
                                on_open=lambda e: OpenThread(e.value), on_delete=lambda e: DeleteThread(e.value))

Functional

from dataclasses import dataclass


@dataclass(frozen=True)
class State:
    threads: tuple = ({"id": "1", "title": "Add a login form", "updated": 0},)
    open_id: str = ""


def view(state, set_state):
    return ui.ThreadHistory(
        threads=list(state.threads), selected=state.open_id,
        on_open=lambda e: set_state(open_id=e.value),
        on_delete=lambda e: set_state(threads=tuple(t for t in state.threads if t["id"] != e.value)))

Properties and API

ui.ThreadHistory

class ThreadHistory

A component for past conversations: a search box and the threads grouped by day (Today, Yesterday, This week, This month, Older), each with a delete button.

Property	Default	Description
threads	None	Dicts or objects with id, title, updated (a timestamp) and an optional detail.
selected	""	The id of the open thread.
theme	None	Theme.

Events: on_open, on_delete (events).

Full reference →

Related

List itemA list row with icon, text and an end slot.

Search inputAn input with a magnifying glass, for filtering.

Virtual listA list that only builds the rows in view, for millions of items.