管理状态

import gradio as gr

# Shared between all users
visitor_count = 0

def increment_counter():
    global visitor_count
    visitor_count += 1
    return visitor_count

with gr.Blocks() as demo:    
    number = gr.Textbox(label="Total Visitors", value="Counting...")
    demo.load(increment_counter, inputs=None, outputs=number)

demo.launch()

import gradio as gr

with gr.Blocks() as demo:
    cart = gr.State([])
    items_to_add = gr.CheckboxGroup(["Cereal", "Milk", "Orange Juice", "Water"])

    def add_items(new_items, previous_cart):
        cart = previous_cart + new_items
        return cart

    gr.Button("Add Items").click(add_items, [items_to_add, cart], cart)

    cart_size = gr.Number(label="Cart Size")
    cart.change(lambda cart: len(cart), cart, cart_size)

demo.launch()

import gradio as gr

class NonDeepCopyable:
    def __init__(self):
        from threading import Lock
        self.counter = 0
        self.lock = Lock()  # Lock objects cannot be deepcopied
    
    def increment(self):
        with self.lock:
            self.counter += 1
            return self.counter

# Global dictionary to store user-specific instances
instances = {}

def initialize_instance(request: gr.Request):
    instances[request.session_hash] = NonDeepCopyable()
    return "Session initialized!"

def cleanup_instance(request: gr.Request):
    if request.session_hash in instances:
        del instances[request.session_hash]

def increment_counter(request: gr.Request):
    if request.session_hash in instances:
        instance = instances[request.session_hash]
        return instance.increment()
    return "Error: Session not initialized"

with gr.Blocks() as demo:
    output = gr.Textbox(label="Status")
    counter = gr.Number(label="Counter Value")
    increment_btn = gr.Button("Increment Counter")
    increment_btn.click(increment_counter, inputs=None, outputs=counter)
    
    # Initialize instance when page loads
    demo.load(initialize_instance, inputs=None, outputs=output)    
    # Clean up instance when page is closed/refreshed
    demo.close(cleanup_instance)    

demo.launch()

import random
import string
import gradio as gr
import time
with gr.Blocks() as demo:
    gr.Markdown("Your Username and Password will get saved in the browser's local storage. "
                "If you refresh the page, the values will be retained.")
    username = gr.Textbox(label="Username")
    password = gr.Textbox(label="Password", type="password")
    btn = gr.Button("Generate Randomly")
    local_storage = gr.BrowserState(["", ""])
    saved_message = gr.Markdown("✅ Saved to local storage", visible=False)

    @btn.click(outputs=[username, password])
    def generate_randomly():
        u = "".join(random.choices(string.ascii_letters + string.digits, k=10))
        p = "".join(random.choices(string.ascii_letters + string.digits, k=10))
        return u, p

    @demo.load(inputs=[local_storage], outputs=[username, password])
    def load_from_local_storage(saved_values):
        print("loading from local storage", saved_values)
        return saved_values[0], saved_values[1]

    @gr.on([username.change, password.change], inputs=[username, password], outputs=[local_storage])
    def save_to_local_storage(username, password):
        return [username, password]

    @gr.on(local_storage.change, outputs=[saved_message])
    def show_saved_message():
        timestamp = time.strftime("%I:%M:%S %p")
        return gr.Markdown(
            f"✅ Saved to local storage at {timestamp}",
            visible=True
        )

demo.launch()