Delphi 6 TRadioGroup with custom TRadioButton controls in it? - delphi

I'm using Delphi 6 (actualy BCB6 but nobody uses that, so Delphi advice is fine). Some controls let you create a custom class of items they can contain, like TListView. Does TRadioGroup have a way to do this without recreating most of the functionality from scratch? I have my own custom TRadioButton derived controls I created that have a custom look, and I'd like all of my radio buttons to match.
I'm not seeing anything possible looking at the source code in extctrls.pas, and not finding anything online, but figured I'd ask because it is late and I might have overlooked something.

TRadioGroup has no such functionality. What you can do is use a TGroupBox to contain your special controls.

Related

Delphi TListBox iOS making new itemstyle/behavior

I need to show custom data. For example I need to show a contact list with name, description, photo. And ideally I would also like to show custom data there, e.g. a button to launch telephone call. The default styles do not quite do what I want, but fairly close.
Thus, as far as I can tell, TListBox could be a decent control for this if I could create custom styles? Is that possible? (Anotther problem of course is setting the values of the custom data controls.)
You should take a good look at the FMX CustomListBox example AFAIK even the example alone already seems to have exactly what you need, already set in place.
It took me about 10 minutes to produce this result straight out of the CustomListBox example with your description:
One thing that the included FMX example demonstrates perfectly is how easy it is to add any FMX control to the ListBox via the TStyleBook Layouts such as buttons, images etc... basically any visual control upon which you then implement the HitTest, again, all very detailed in the FMX Delphi example.

How to write a custom Button component?

I have been making components for Delphi for a couple months now. Currently I am extending the TButton to create another form that has 20 or so components on it. I have done this recently and just created everything dynamically in click event. Is there a way to create to form and have it compiled into the component so I can use the IDE to design the form?
Thank you
Yes. Simply add your TForm unit to your button's Package, and then you can design it like any other project.

Delphi buttons show white border on Aero glass

I have been trying to find a good-looking design using Aero in Delphi 2010. One of the obvious uses one sees, is where the glass frame is extended to include the OK/Cancel buttons at the bottom of the screen. I notice though that this doesn't look quite right in Delphi 2010 - there is a white border all around each button.
This image shows the problem: the top 3 buttons are from my app, the bottom two were taken from Paint.NET's Layer Properties dialog.
I tried various combinations of DoubleBuffered and a few combinations of placing the controls on other controls first, but the problem remains. Any ideas?
If no one has a clean solution, as a workaround use TBitBtn with DoubleBuffered = false.
It appears that the only workaround is owner-draw, or a third-party button control Check out the Glass Button by Roy Klever or, as stated in the QC entry linked below, TBitBtn with DoubleBuffered=false, which was the accepted answer above to this question.
This is a bug in Windows Aero DWM or else a bug in the windows common controls, or a bug in the way the VCL class hierachy handles common control window messages and painting when painting on glass. In short, windows common controls do not paint themselves properly on glass, or rather DWM composition (Aero) is broken. Surprise surprise.
The standard VCL button component uses the Window Class BUTTON from Windows Common Controls.
Note that TSpeedButton does not use the windows common control, and does not have this problem. however, it also does not accept focus.
It appears Embarcadero knows about this issue, it is QC # 75246, which is closed because it is really a bug in the common controls library, as Won't Fix, with the suggestion to use TBitBtn. Buttons are not alone, this is part of a group of QC reports including panels, and other common controls.
However I have a commercial TcxButton (part of developer express components) which accepts keyboard focus, and does not draw this glitch. Any code that uses the Win32 common control button control appears to have this problem. It may be possible that a low level Win32 API hacker might find a workaround for this. I am looking into it. This answer will be updated if I figure it out.
One interesting detail: TcxButton has three drawing styles, cxButton.LookAndFeel.Kind = {lfOffice11,lfFlat,lfStandard}. Selecting lfOffice11 adds this glitch back in. It looks like a strange interaction between the glass feature in aero in Vista/Win7 and the common control/xptheme button drawing code.
It may be that the only workaround is to use a completely app-drawn button control and to not use Windows common controls buttons, or any button control that relies upon the XP theme engine to draw buttons, on an aero glass pane.
Edit: July 28, someone at Embarcadero has closed the above QC Entry, which was a mistake. I am urging them to reopen it, if only to clarify if this is indeed a Windows bug in the common controls dll.
If you wish to play around, make a copy of the VCL source code for the TButton and TCustomButton classes from StdCtrls, as I have done here, modify CNCtlColorBtn, so that you force one of three things to happen - PerformEraseBackground, DrawParentBackground or inherited, and see the results. Interesting stuff.
procedure TCustomGlassButton.CNCtlColorBtn(var Message: TWMCtlColorBtn);
begin
PerformEraseBackground(Self, Message.ChildDC);
Message.Result := GetStockObject(NULL_BRUSH);
(*
with ThemeServices do
if ThemesEnabled then
begin
if (Parent <> nil) and Parent.DoubleBuffered then
PerformEraseBackground(Self, Message.ChildDC)
else
DrawParentBackground(Handle, Message.ChildDC, nil, False);
{ Return an empty brush to prevent Windows from overpainting we just have created. }
Message.Result := GetStockObject(NULL_BRUSH);
end
else
inherited;
*)
end;
Some interesting reading on Vista era glass/DWM/aero APIs (C++ developers blog)
Here I'm providing some code that makes TButton look right on Glass. Unfortunately it makes the form "click-throw", so I don't think it's a good idea. But maybe you can find a way to fix the form's "click-throw".
if you are able to use win32 api, try exploiting NM_CUSTOMDRAW notification (not ownerdraw), as i do (yes, buttons DO send it, including radio and checkboxes. For these it is best to use WM_CTLCOLORSTATIC though.). This is how it is done in C++, but the idea is the same. While my idea is good, it so happens that my buttons do DISAPPEAR once per program execution from the window, when they are customdrawn and i need to hover mouse over them so they are visible again. That's why i'm still looking for comments for this. Note that it is really difficult to reproduce disappearing buttons in one-form applications. I hovewer am experiencing this behaviour in every project.
case WM_NOTIFY:
switch(((LPNMHDR)lParam)->code){
case NM_CUSTOMDRAW:
{
NMHDR *nmh=(NMHDR*)lParam;
//these 6000 through 6004 are button identifiers assigned by me
if(nmh->idFrom >= 6000 && nmh->idFrom <= 6004){
switch(((LPNMCUSTOMDRAW)nmh)->dwDrawStage){
case CDDS_PREERASE:
//BackgroundBrush is a HBRUSH used also as window background
FillRect(((LPNMCUSTOMDRAW)nmh)->hdc, &((LPNMCUSTOMDRAW)nmh)->rc, BackgroundBrush);
break;
}
}
break;
}
break;

Where can I find a movable toolbar demo?

At the top of the Delphi IDE is a toolbar with buttons grouped together on little movable trays. I'm trying to implement something like that, but not having much success. I've found TToolbar, but I can't figure out how to set up the movable trays. Does anyone know where I could find a simple demo app that shows how it's done?
I believe the webbrows.dpr located in the cool stuff demo directory (and included in all installs of Delphi since around Delphi 6 or so) contains just the demo you are looking for. This gives you the effect your looking for using only CodeGear supplied components. You add multiple bands and set the fixed size to false for the bands you want to allow to be movable.
You can try the Toolbar2000 Component from Jordan Russell or the TBX package wich is an extension for Toolbar2000 components.
Toolbar2000 is a set of components for CodeGear Delphi and C++Builder designed to mimic the Office 2000 look and behavior. It includes draggable and dockable toolbars and menus.
alt text http://www.indasoftware.com/_files/img/fordev/office2003/small_classic.png
you can see these links.
Office2003 Theme for TBX
Mac OSX Theme for TBX
TBX themes
Bye.
You can put your toolbars in a standard VCL TCoolBar or TControlBar. AFAIR this can get a bit messy sometimes. For an example, have a look at the CoolStuff demo, as skamradt suggested.

DateTimePicker Alignment in Delphi 7

My problem is following: I need to align text inside DateTimePicker component to center. This component however doesn't have Alignment property. This component comes from TCommonCalendar, which also doesn't have this property. Can anybody think of possible solution?
Thank you,
Tofig Hasanov
There are many alternatives to TDateTimePicker out there, for a reason: They can the stuff that TDateTimePicker cannot.
I doubt it is possible.
Behind the scenes, when you create a TDateTimePicker, a window common control SysDateTimePick32 get's created. It looks like it does not allow it's Style to be changed from ES_LEFT to ES_CENTER (or ES_RIGHT for that matter).
I hope to be proven wrong.

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