Handling "Back" Softkey Events

[lvngt5gj9]

Hi,

I've searched high and low for this but can't find an answer...

When a user presses the "back" key (i.e. the right softkey) to move back a screen in an application, how do I catch this?

I know that when the right softkey displays "Exit" you can catch this with the handler...

appuifw.app.exit_key_handler

...but can I handle the event when the right softkey does a "back" to a previous screen in a gui ?

Thanks for any help,

M.

[zell1983]

try with this:
appuifw.app.menu = []
appuifw.app.menu.append((u"back",self.func))
Where self.func is the function that handle the callback.
bye

[lvngt5gj9]

Here's an example of what I mean.

When you run the script below after the info message you are presented a single choice.

The left softkey displays "OK" and chooses the option. The right softkey shows "Exit". Hitting exit at this point calls the exit_key_handler. So far so good.

When the option is chosen a simple form is shown. The softkeys now read "Options" and "Back".

What I'd like to do is trap the "Back" event, and make it call show_main_view again (i.e. display the info message again).

Thanks again.

M.

import e32
import appuifw

class Test:
    def __init__(self):
        self.lock = e32.Ao_lock()
        appuifw.app.exit_key_handler = self.abort
        self.exit_flag = False
        
    def show_main_view(self):
        appuifw.note(u"Hello", 'info')
        self.choice = [(u"Choice 1") ]
        self.lb = appuifw.Listbox(self.choice, self.callback)
        appuifw.app.body = self.lb

    def callback(self):
        self.fields = [(u"Text Field", 'text') ]
        self.form = appuifw.Form(self.fields, appuifw.FFormDoubleSpaced)
        self.form.execute()       
        
    def abort(self):
        self.exit_flag = True
        self.lock.signal()

    def run(self):
        while not self.exit_flag:
            self.show_main_view()
            self.lock.wait()

if __name__ == "__main__":
    old_title = appuifw.app.title
    old_exit_key = appuifw.app.exit_key_handler
    try:
        appuifw.app.title = u"Test"
        e32.ao_yield()
        app = Test()
        app.run()
    finally:
        appuifw.app.set_tabs([], None)
        appuifw.app.exit_key_handler = old_exit_key
        appuifw.app.title = old_title

[Zen13546]

I am not sure what do you think, but you just need to do something when you leave the form.

I would try this

    def callback(self):
        self.fields = [(u"Text Field", 'text') ]
        self.form = appuifw.Form(self.fields, appuifw.FFormDoubleSpaced)
        self.form.execute()       
        # here insert  the code

[lvngt5gj9]

Thanks for the tip Zen.