Re: [Pythoncard-users] dbbrowser sample - creating widgets at runtime?

[Kevin A. <al...@se...>]

On Sep 3, 2004, at 11:42 AM, Gregory Pi=F1ero wrote:

> Hi,
>
> I'm looking at the dbrowser sample.  On my computer this is the file: =20=

> C:\Python23\Lib\site-=20
> packages\PythonCard\samples\dbBrowser\dbBrowser.py
>
> So this thing when running seems to know the number of columns in any =20=

> table I connect to and then (creates?) that many text boxes to show =20=

> the values of each column.  Does anyone know how this would work?  How =
=20
> are the text boxes created on the fly like that?
>
> I was unable to locate any documentation on this this and I can't see =20=

> how it does it from the code.
>
> Thanks,
>
> Greg

Creating components on the fly is easy, you just need to provide a =20
dictionary of the key:value pairs. Just look at the dictionaries for =20
each component in any .rsrc.py file and you'll see the same kind of =20
dictionary in use. For example, to create a button named 'btn1' in your =20=

code you might do something like:

self.components['btn1'] =3D {'type':'Button', 'name':'btn1', =20
'position':(0, 30), 'label':'btn1 hello'}

So, let's say you want to dynamically create 10 single-line fields when =20=

your application starts up. Here's one way you might do it:

     def on_initialize(self, event):
         insetFromEdge =3D 5
         padding =3D 4
         self.components['field0'] =3D {'type':'TextField', =20
'name':'field0', 'position':(5, 5), 'text':'field0'}
         height =3D self.components.field0.size[1]
         for i in range(1,10):
             name =3D 'field' + str(i)
             position =3D (insetFromEdge, insetFromEdge + i * (height + =20=

padding))
             text =3D name
             self.components[name] =3D {'type':'TextField', 'name':name, =
=20
'position':position, 'text':text}

I'm creating the first TextField outside the loop so that I can get the =20=

height of a TextField dynamically, which allows the code to work =20
regardless of the default text height on any given platform. You could =20=

just as easily, initialize the height to 0 and do an if block after the =20=

self.components[name] line to set the height.

ka=