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RB 14

edited November 2011 in Component Writing
Greetings,

Up to RB 12.05 Pro I have been using several custom components that I've
made that draws directly to either the printer canvas or the screen canvas.
With RB 14 TppScrollableScreenDevice is new. I've tried drawing to its
canvas with no success. In the Report Designer - Preview my component does
not show up unless I set the report's preview form setting to single page.
Is there another canvas that I need to be drawing to?

I am currently using Delphi 2007, RB 14, Windows 7 Ultimate.

Regards,

Tommy Dillard

Comments

  • edited November 2011

    If you have a DrawCommand descendant class, with some code like this...

    function TmyDrawCommand.Draw(aDevice: TppDevice): Boolean;
    begin

    ...
    else if (aDevice is TppScreenDevice) then
    begin
    lCanvas := TppScreenDevice(aDevice).Canvas
    end

    end

    then you will need to change it to this..

    uses
    ppGraphicsDevice;

    .....

    else if (aDevice is TppGraphicsDevice) then
    begin
    lCanvas := TppGraphicsDevice(aDevice).Canvas
    end;


    TppGraphicsDevice was introduced in RB 12 and is the ancestor of any device
    that renders to a canvas. For RB 14 the hierachy looks like this...

    TppDevice
    TppGraphicsDevice
    TppCustomScreenDevice
    TppScreenDevice
    TppScrollableScreenDevice


    Sorry that I did not think of this when you emailed support@ last week,
    reading the wording of this post about 'drawing to the canvas' triggered in
    my mind what has changed from the DrawCommand perspective.


    -
    Nard Moseley
    Digital Metaphors
    www.digital-metaphors.com

    Best regards,

    Nard Moseley
    Digital Metaphors
    www.digital-metaphors.com
  • edited November 2011
    Nard,

    Thank you.

    Best Regards,
    Tommy Dillard

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