[Lazarus] TextHint in TComboBox

[Ondrej Pokorny]

On 13.08.2020 17:58, Juha Manninen via lazarus wrote:
> On Thu, Aug 13, 2020 at 6:50 PM Juha Manninen <juha.manninen62 at gmail.com> wrote:
>> AFAIK it is not emulated on Windows. LCL-Win32 reports LCLCapability
>> flag lcTextHint.
> Actually it is emulated for older Windows versions.
> function TWin32WidgetSet.GetLCLCapability has :
>    ...
>      lcTextHint:
>      begin
>        if (ComCtlVersion >= ComCtlVersionIE6) then
>          Result := LCL_CAPABILITY_YES
>        else
>          Result := LCL_CAPABILITY_NO;
>      end;
>
> For Windows 10 it should report LCL_CAPABILITY_YES.

Funnily I tested with themes off, so I got LCL_CAPABILITY_NO :)

But yes, you are correct. That is not optimal. We need to split 
lcTextHint into lcTextHintEdit and lcTextHintMemo. Because as I wrote 
before WinAPI doesn't support TextHint for multi-line text boxes 
(TMemo): 
https://docs.microsoft.com/en-us/windows/win32/api/commctrl/nf-commctrl-edit_setcuebannertext

So for TMemo we need the emulated code, which works now with a minor bug 
(the TextHint is not visible when the form is shown the first time). 
Strangely the bug is present only in a themed application, not in an 
unthemed one.

Ondrej