import panel as pn
import asyncio

pn.extension()

button = pn.widgets.Button(name='Click me!')
text = pn.widgets.StaticText()

async def run_async(event):
    text.value = f'Running {event.new}'
    await asyncio.sleep(2)
    text.value = f'Finished {event.new}'

button.on_click(run_async)

pn.Row(button, text)

import numpy as np
from bokeh.plotting import figure
from bokeh.models import ColumnDataSource

button = pn.widgets.Button(name='Click me!')

p = figure(width=500, height=300)
cds = ColumnDataSource(data={'x': [0], 'y': [0]})
p.line(x='x', y='y', source=cds)
pane = pn.pane.Bokeh(p)

@pn.io.with_lock
async def stream(event):
    await asyncio.sleep(1)
    x, y = cds.data['x'][-1], cds.data['y'][-1]
    cds.stream({'x': list(range(x+1, x+6)), 'y': y+np.random.randn(5).cumsum()})
    pane.param.trigger('object')
    
# Equivalent to `.on_click` but shown
button.param.watch(stream, 'clicks')

pn.Row(button, pane)

import time
import threading

c = threading.Condition()

button = pn.widgets.Button(name='Click to launch')
text = pn.widgets.StaticText()

queue = []

def callback():
    global queue
    while True:
        c.acquire()
        for i, q in enumerate(queue):
            text.value = f'Processing item {i+1} of {len(queue)} items in queue.'
            time.sleep(2)
        queue.clear()
        text.value = "Queue empty"
        c.release()
        time.sleep(1)
        
thread = threading.Thread(target=callback)
thread.start()

def on_click(event):
    queue.append(event)

button.on_click(on_click)

pn.Row(button, text).servable()