How to Mousewheel capture in Tumbviewer?
lazarus / 39-Graphics

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barsoom · 2020-06-22 23:44

Thumbcontrol.pas unit handle the keys up, down right, left and enter
keys, however, not the mousewheel.
How can i do the selected picture move up/down in the vertical layout
of thumviewer when using the mousewheel?
Thanks.

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wp · 2020-06-23 22:16

In which package is this ThumbControl?

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barsoom · 2020-06-25 18:34

Thumbviewer

https://github.com/theo222/lazarus-thumbviewer

I have a Thumbcontrol component in the main form with a vertical
layout. What i need is to move up or down the scroll by using the
mousewheel, as it occurs whwn uning the up and down keys of the
keyboard.

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flowCRANE · 2020-06-26 02:13

Just add the WMMouseWheel and WMMouseHWheel message handlers and in
them call the method responsible for scrolling the component using the
keys.

Code: Pascal  [Select][+][-]window.onload = function(){var x1 =
document.getElementById("main_content_section"); if (x1) { var x =
document.getElementsByClassName("geshi");for (var i = 0; i procedure
WMMouseWheel(var Message: TLMMouseEvent); message
LM_MOUSEWHEEL;procedure WMMouseHWheel(var Message: TLMMouseEvent);
message LM_MOUSEHWHEEL;
Check what the Messsage argument has, recognize horizontal/vertical
direction and, on the basis of recognized direction, pass the
appropriate key constant (in the form of variable) to the KeyDown
method. Or simply modify the component code (without inheritance),
copy the parts of the logic from the KeyDown method to the message
handlers and that's it.

I don't know this component, I've never seen or used it, but it should
work fine.