暂停 Jupyter Notebook 小部件，等待用户输入

Question

我遇到了与 TheInterestedOne 提出的 here 相同的问题。

我需要为用户创建两个按钮，并建议用户点击循环中的两个按钮之一；以便循环的下一次迭代仅在用户选择之后发生。

我阅读了this source，但我无法让它适用于按钮。我不明白，在使用按钮的情况下，小部件属性如何变化。

from functools import wraps
def yield_for_change(widget, attribute):
    def f(iterator):
        @wraps(iterator)
        def inner():
            i = iterator()
            def next_i(change):
                try:
                    i.send(change.new)
                except StopIteration as e:
                    widget.unobserve(next_i, attribute)
            widget.observe(next_i, attribute) //**button.on_click(on_button_clicked) 
                                                                may be?**
            # start the generator
            next(i)
        return inner
    return f


from ipywidgets import Button
button=Button()


def on_button_clicked():
    print("Button clicked.")


@yield_for_change(button, 'value')
def f():
    for i in range(10):
        print('did work %s'%i)
        x = yield
        button.on_click(on_button_clicked)

Answer 1

此版本使用awaitio 并针对按钮进行了修改。

from ipywidgets import Button
import asyncio

def wait_for_change(widget):
    future = asyncio.Future()
    def getvalue(change):
        future.set_result(change.description)
        widget.on_click(getvalue, remove=True) 
        # we need to free up the binding to getvalue to avoid an InvalidState error
        # buttons don't support unobserve
        # so use `remove=True` 
    widget.on_click(getvalue)
    return future

button = Button(description="wow")

list_to_tag = ["one", "two", "three", "four"]

async def f():
    for i in list_to_tag:
        print("going to tag {}".format(i))
        x = await wait_for_change(button)
        print("tagged {} with {}".format(i, x))
        print()

asyncio.create_task(f())
button

Answer 2

要拥有多个按钮，您可以将其他小部件添加到 @IanMulvany 先前的答案之一。

请参阅下面代码中的

from ipywidgets import Button, HBox #<----- Add HBox for displaying multiple buttons
import asyncio

def wait_for_change(widget1, widget2): #<------ Rename to widget1, and add widget2
    future = asyncio.Future()
    def getvalue(change):
        future.set_result(change.description)
        widget1.on_click(getvalue, remove=True) #<------ Rename to widget1
        widget2.on_click(getvalue, remove=True) #<------ New widget2
        # we need to free up the binding to getvalue to avoid an IvalidState error
        # buttons don't support unobserve
        # so use `remove=True` 
    widget1.on_click(getvalue) #<------ Rename to widget1
    widget2.on_click(getvalue) #<------ New widget2
    return future

button1=Button(description="wow") #<------ Rename to button1
button2=Button(description="wow2") #<------ New button2 and description

list_to_tag = ["one", "two", "three", "four"]

async def f():
    for i in list_to_tag:
        print('going to tag ', i)
        x = await wait_for_change(button1,button2) #<---- Pass both buttons into the function
        if x == "wow": #<--- use if statement to trigger different events for the two buttons
            print("tagged ", i, "with  %s"%x)
        else:
            print(i, "tagged with %s"%x)
        print("")
        print("")

asyncio.create_task(f())
HBox([button1,button2]) #<----Display both buttons in an HBox

Answer 3

这是适用于Button 的示例。主要变化在于装饰器，将observe 替换为on_click，这在某种程度上相当于观察按钮。

from functools import wraps
def yield_for_change(widget):
    def f(iterator):
        @wraps(iterator)
        def inner():
            i = iterator()
            def next_i(change):
                try:
                    i.send(change)
                except StopIteration as e:
                    widget.unobserve(next_i, attribute)
            widget.on_click(next_i)
            # start the generator
            next(i)
        return inner
    return f


from ipywidgets import Button
button=Button()

def on_button_clicked():
    print("Button clicked.")


@yield_for_change(button)
def f():
    for i in range(10):
        print('did work %s'%i)
        x = yield

f()

button