Subject Re: Closing an image on a form
From Mervyn Bick <invalid@invalid.invalid>
Date Wed, 7 Apr 2021 15:12:16 +0200
Newsgroups dbase.getting-started

On 2021/04/07 11:39, royprice wrote:

> Hello Akshat,
> This is the code that currently displays the images in three areas...
>   this.IMAGEPHOTO01 = new IMAGE(this)
>     with (this.IMAGEPHOTO01)
>        onOpen = class::IMAGEPHOTO01_ONOPEN
>        onClose = class::IMAGEPHOTO01_ONCLOSE
>        height = 21.5
>        left = 89.0
>        top = 16.5
>        width = 87.0
>        dataSource = form.cactusaadatamodule1.photos01_dbf1.rowset.fields["photo"]
>        alignment = 3        // Keep Aspect Stretch
>     endwith
>     this.IMAGEPHOTO02 = new IMAGE(this)
>     with (this.IMAGEPHOTO02)
>        height = 17.5
>        left = 176.0
>        top = 0.5
>        width = 82.0
>        dataSource = form.cactusaadatamodule1.photos02_dbf1.rowset.fields["photo"]
>        alignment = 3        // Keep Aspect Stretch
>     endwith
>     this.IMAGEPHOTO03 = new IMAGE(this)
>     with (this.IMAGEPHOTO03)
>        height = 19.5
>        left = 176.0
>        top = 18.0
>        width = 82.0
>        dataSource = form.cactusaadatamodule1.photos03_dbf1.rowset.fields["photo"]
>     endwith

Another of my assumptions when I put together that little example was
that you only had one image control on your form.   Having three image
controls seems, on the face of it, to be a waste of space on the form.
On the other hand if your application really calls for three image
controls then so be it.

> Straightforward.....
> And this is my attempt to deal with the problem (which doesn't work).
> Also tried the same with OnClose()
>   function IMAGEPHOTO01_onOpen()
>         do case
>                  case  form.cactusaadatamodule1.cactusaa_dbf1.rowset.fields["photoyesfile"]='02'
>                  dataSource = form.cactusaadatamodule1.photos02_dbf1.rowset.fields["photo"]
>                 case  form.cactusaadatamodule1.cactusaa_dbf1.rowset.fields["photoyesfile"]='03'
>                 dataSource = form.cactusaadatamodule1.photos03_dbf1.rowset.fields["photo"]
>                 case  form.cactusaadatamodule1.cactusaa_dbf1.rowset.fields["photoyesfile"]='01'
>                 dataSource = form.cactusaadatamodule1.photos01_dbf1.rowset.fields["photo"]
>                 otherwise
>                         dataSource = form.cactusaadatamodule1.photos02_dbf1.rowset.fields["photo"]
>                 endcase
>        return

This would take care of displaying the correct photo for the first
record in your main table.  The syntax is, however, not quite correct.
In addition the approach is wrong if you actually have three separate
image controls on your form.  Try the following.

    function IMAGEPHOTO01_onOpen()
         this.dataSource =
         this.datasource = []

You will need a similar onOpen event handler, with the necessary
changes, for each image control.  This will leave one image control
displaying an image with the other two blank.

If you decide to use only one image control so as to save space on the
form with the added bonus of not have two empty image controls then the
following onOpen event handler will do the job.

function IMAGEPHOTO01_onOpen()
         this.dataSource =
         this.dataSource =
         this.dataSource =

As an aside the if...elseif...else...endif contruct has exactly the same
effect as a do construct.  I prefer it
as it requires less typing and I'm a lazy typist. :-)  If you are
happier with do case then by all means stick with it.

The next step is to deal with updating the image controls as you
navigate through the main table.

The way to do this is to use the main rowset's onNavigate event handler.
  If you are using three image controls set the datasource property for
the appropriate image control and null the other two by assigning [] to
their datasource properties.   If you are using one image control simply
set the datasource as appropriate for the value in the photoyesfile field.

Any rowset event handler doesn't understand the concept of "form" so one
needs to use this this.parent.... instead.  This is made trickier as
using a datamodule adds an extra parent into the mix.

I'm taking a break now to watch the rest of the ODI cricket match
between Pakistan and South Africa but I'll give you some code tomorrow.
  Unless someone else does so first. :-)