[aneville]

Hey,

I'm trying to write an SMS composer that captures key events. I have written two independent programs but I'm having trouble integrating them. For the key event program, I'm setting the the following:

canvas = appuifw.Canvas(redraw_callback = redraw_callback, 
                        event_callback = event_callback)
appuifw.app.body = canvas

and my SMS composer application sets the following:

appuifw.app.body = appuifw.Text()

How can I go about integrating this so that I have a appuifw.Text() body that allows entering text while capturing the events at the same time?

Many Thanks,

A

[pavan.pareta]

Hi,


you have to write your own separate method for getting key value, while any key is pressed and you have to find it out which key is pressed by the user.

Hope this may be help.

[aneville]

The method I was using was a callback function. I have appended the full code below that I'm using to capture the key events. Note how appuifw.app.body is utilising a callback function to capture these events.

import e32, appuifw, datetime

canvas = None
text = ''
keymap = {}
firstTimeKeyPressed = True

def getFlightTime(sTime):
    global firstTimeKeyPressed
    global keyPressTime
    global keyDelta

    if firstTimeKeyPressed:
        firstTimeKeyPressed = False
        keyPressTime = sTime
    else:
        keyDelta = datetime.datetime.now() - keyPressTime
        keyPressTime = datetime.datetime.now()
        return keyDelta

def event_callback(event):
    global text
    pressTime = datetime.datetime.now()
    flightTime = getFlightTime(pressTime)
    if canvas is None:
        return
    eventType = event['type']
    scancode = event['scancode']
    if eventType == appuifw.EEventKeyDown:
        keymap[scancode] = datetime.datetime.now()
        text = 'KeyDown %d' % scancode
        redraw()
    elif eventType == appuifw.EEventKeyUp:
        try:
            delta = datetime.datetime.now() - keymap[scancode]
            del keymap[scancode]
        except KeyError:
            delta = -1
        releaseTime = datetime.datetime.now()
        text = '\n%s\n%s\n%d\n%s\n%s' % (pressTime, flightTime, scancode - 48, delta, releaseTime)
        print text
        redraw()
        
def redraw_callback(bounds):
    redraw()

def redraw():
    if canvas is None:
        return
    canvas.clear()
    canvas.text((10, 20), unicode(text))

canvas = appuifw.Canvas(redraw_callback = redraw_callback,
                        event_callback = event_callback)
appuifw.app.body = canvas
lock = e32.Ao_lock()
appuifw.app.exit_key_handler = lambda: lock.signal()
lock.wait()

However, I want to make this application look like an SMS composer by using appuifw.app.body = appuifw.Text(), but this overwrites the callback function. Is there any way to achieve this or do i need to take a new approach?

[bogdan.galiceanu]

If detecting keypresses and not key up or key down events is enough you can use the keycapture module. Otherwise you might be able to use your own Keyboard class that detects events, like in this article. Haven't tested it though.

[aneville]

bogdan.galiceanu: Thanks for your reply. Originally I implemented the Keyboard class but this has some problems whereby it made it difficult for me to add specific methods i required (like getting fligh times of keys and dwell times) as detailed in my previous example. Additionally, their method for checking is a key pressed (polling) is really inefficient as it's really heavy on power consumption. Regardless of this, the article which you linked me to exhibits the same problem whereby their Keyboard class is initiated using the

app.body = canvas = Canvas(event_callback=key.handle_event)

This will stops me from actually entering text into a Text() body. Surely there must be a way to do this?