app.py

import gradio as gr

with gr.Blocks() as demo1:
    show_box = gr.Checkbox()

    @gr.render(inputs=show_box)
    def render(show_box):
        if show_box:
            textbox = gr.Textbox()
            textbox2 = gr.Textbox()
            textbox.change(lambda x:x, textbox, textbox2)
        else:
            gr.Markdown("Hidden textbox")

#demo.launch(debug=True)

import gradio as gr

def predict(*args):
    print(args)
    return {"inputs": list(args)}

with gr.Blocks() as demo:    
    s = gr.Slider(1, 4, step=1, interactive=True)

    @gr.render(inputs=s, triggers=[s.change])
    def render(num):
        texts = []
        with gr.Row():
            for i in range(num):
               texts.append(gr.Textbox())
        json = gr.JSON()
        btn = gr.Button("RUN")
        btn.click(fn=predict, inputs=texts, outputs=json)
demo.launch(debug=True)