有没有通过javascript触发某消息函数的机制？

[honesthnter]

有没有通过javascript触发某消息函数的机制？

[wang0618]

使用底层的 output_register_callback() 注册一个回调函数来获取回调id，然后在前端调用 WebIO.pushData() 并传入回调id：

from pywebio.output import *
from pywebio import session
from pywebio.io_ctrl import output_register_callback

def click_callback(val):
    put_text(val)

callback_id = output_register_callback(click_callback)

session.run_js("WebIO.pushData('data', callback_id)", callback_id=callback_id)

[honesthnter]

感谢，用上了，实现了一个表格点击事件的回调，实现点击表头排序及点击下钻等功能。

[bengulliano]

Hi Please can you give a little bit of example how this can be achieved using Coroutine-based session and start_server.

In the above example the output_register_callback(click_callback) and session.runjs are both executed on the server side.

How can one register the callback and pass the callback id to the client so it can be used in the client. I guess this can be done through the session. But can one use session when the server has not started?

start_server will block until the window is closed, so I cannot place code after start_server

[wang0618]

from pywebio.output import *
from pywebio.io_ctrl import output_register_callback


def click_callback(val):
    put_text(val)


def main():
    callback_id = output_register_callback(click_callback)

    put_html("""
    <button onclick="send_data()">Click me</button>
    <script>
    function send_data(){
        WebIO.pushData('data', %r)
    }
    </script>
    """%callback_id)


start_server(main, port=8080, debug=True)

[wang0618]

You can build your own widget which can post data back by using output_register_callback() and put_html()

[bengulliano]

Hi Wang, wow, thanks for that quick reply., sure did help to remind of some of the things I may have forgotten for example:

Server can pass objects and information to the client before rendering and it will still be in the session scope. Just like it is done when using PHP. And that opens a lot of possibilities.

I must say this is a great tool you have made. Thumbs up.