Alternative for TCategoryPanelGroup or TPageControl - delphi

Does an alternative exist for TCategoryPanelGroup or TPageControl? My problem is I use a CategoryPanelGroup on a PageControl, therefore there is an enormous flicker which I can not prevent (using DoubleBuffered, disabling a ParentBackground and other things).
I use TPageControl as panels, to show/hide groups of controls.

If you don't need to show tabs, don't use a page control.

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TPageControl component in Delphi 2006

Is there an option to use same components (check boxes, TEdits, etc.) on different tabs on TPageControl component?
Not directly, no because each page is a separate object. If you want to use the same controls on every page, use TTabControl instead.
If you need to use TPageControl, there are ways to dynamically move controls between pages but usually it is simpler to just copy and paste.

How to get the handle of the splitter between docked forms

I docked two forms on a panel.
It will create a splitter automatically.
Is it possible to get the handle of the splitter using code?
No, it's not possible to get the handle of that control. Splitter controls descend from TGraphicControl, so they do not have window handles.
Whatever your reason for wanting a handle, you'll need to find some other solution to the problem you thought it would solve.

Caption for TTabControl

I'm looking for a way of implementing a sort of inset caption before a set of tabs, something like this:
The tab set is not supposed to be multi-line, will only be horizontal and laid out at the top. However it should be correctly scrollable when there are too many tabs.
I fear I'm going to be restricted here with regard to using third-party controls, but I could use subclassing on the standard TTabControl to add the necessary changes to the standard looks and behaviour. (I don't need it to be TPageControl, because it's only the specific arrangement of the tabs that I am interested in.)
Maybe there's some way of implementing this with craftily arranged combination of standard controls, which, despite my endevours, has escaped me.
Basically, any ideas or pointers are welcome.
Oh, and additional requirement is, it should blend well with desktop themes.
Granted some time has passed, but I recently needed this style and found you can do it with the TMS Software TAdvOfficePager. It has a property FixedTabs, which I set to 1 in this case. It also has an OnChanging event where you can prevent access to a tab, in this case I used AllowChange := (ToPage > 0); Lastly, I set the first tab to disabled.
Then just style the first tab different than the rest and you can have something like this:
Have you tried to make the first tab to be the caption you want.
With some additional logic you can restrict the selection of this tab.
I don't know if you can control the style of each tab individually to make the first one look as it is not the tab.
Here is crafty arrangement of controls that will work. I have done this sort of thing in the past. Best of all it automatically handles scrolling of tabs.

Delphi: Managing multiple instances of TFrames

In this article there is an explanation of how to use TFrames as an alternative to TTabSheets in a Delphi PageControl.
I've been pondering a similar exercise, which the above doesn't seem to provide the solution for, and for which my solution seems to be overly complicated.
The requirement is for a tabbed interface, where each tab can be one of a number of different designs. Each design is implemented as a TFrame.
Due to the nature of the application being designed, we may have multiple copies of any frame open at any particular moment (with the content of each tab differing, but not the design) so that the user can compare the details of 2/3 different items at the same time.
For example in one session we may have 3 tabs open, all of Frame design A.
On another occasion we may have 3 tabs open each of Frame A, B and C.
The design needs to be flexible enough that we can add Frames to the design on request.
At the moment the solution that I have is to have separate TLists managing each type of Frame that we have open, with perhaps a master TList to keep track of the tabs that are open. As I said, over complicated.
Does anyone have a suggestion of how this could be handled more simply?
I'd probably leave out the master TList of frame instances.
If you need them you'll be able to get them by interrogating the TPageControl directly or through each of your individual TLists for each frame type.
Apart from that your approach sounds reasonable.
I have an application that manages frames on a single panel with my own menu control to control which frame is visible. When I need to make a frame visible I simple set visible:=false for every frame on the panel except for the one that I want. I am in control of what goes onto the panel so I know that at the very least each control is a Tframe and I can get to each frame by iterating over the Panel's Controls property. I then use interfaces to communicate between my main form and my frames.
Now if you want to use a standard windows tabbed interface you could still use the page control as you have suggested, you know that each TtabSheet has a single Tframe on it and you can check it's type and work with it as required. I don't see why you'd need a Tlist because if you really need to get at the "list of Tframes" you could build it dyamically anyway by iterating over the TtabSheets in the page control.
An alternative which would work similarly to my first approach, but gets you nice Windows tabs, would be to use a TtabControl instead of a TpageControl. With the TtabControl you basically just get a Tstrings instance (in the Tabs property) which represents all of the tabs. Since it's a Tstrings you can associate an object (ie your Tframe) with each item and hence each tab. When you click a tab you hide everything and show the correct Tframe. You also have your list because it's attached to the TtabControl via the Tabs property. You just have to handle the visibility of the frames yourself.
We use a TPageControl and create runtime a TTabSheet descendant, which has a new property for our own TFrame (we do not need to scan through .Controls or .Components to search our frame each time).

Fluid Form Layout in Delphi

We have developed a software. In this software we are show and hiding a few controls on various input screens depending on various situations.
When we hid a control what happens is that the space occupied by that control is left as it is and layout looks very bad at times esp. in screens that have larger numbers of controls. Our client does not like this and has asked us to do something about this.
My question:
Is there some way by which we can create Fluid Layouts so that when a control is hidden the rest of the controls automatically adjusts themselves to fill the empty space left by the control hidden and when the control is show they should automatically make way for the control and adjust themselves accordingly.
I know we can achieve this by coding but that will require a lot of code in each screen for adjusting the layout. I am looking something which will reduce coding in each screen as there are 80+ screens.
Please suggest some way which is less error pron and can get rid of unnecessary coding in each input screen.
I think your best option is to use a component that handles the layout of your vcl controls on your form in runtime (depending on the conditions that you define). I recommend you try the Devexpress ExpressLayout Control
you can find two great demo videos here
ExpressLayout Control - How to Customize Layout Views
ExpressLayout Control - Create and Customize a Simple Layout
(source: devexpress.com)
You can check these features
Auto-Management - Control groups and individual control elements are automatically managed by the Layout Control. You never worry about pixel-by-pixel positioning.
Form auto-sizing - The form can be automatically resized to fit its contents best.
Bye.
Now, I'm not sure how complex layout you have, but I guess you can use TFlowPanel and/or TGridPanel for this. Flowpanel has a nice handling of components that change visiblity. I'm not sure how well gridpanel handles the same...
What kind of controls are you dynamically hiding, and what do you mean with auto fill space?
I do not know if it is as this simple: place controls on panels, and use align alTop/alClient/alBottom. When you hide a panel, all other panels will move automatically up.
One problem though: if you want to show a panel again, the order of panels can sometimes be screwed up... Can be fixed by manually setting .Top property, or "hide" by setting .Height := 1;
What I would do with a complex layout is actually split it up into several tabs. This has two advantages. It simplifies the form layout, and allows you to show and hide whole tabs depending on choices made in other tabs.
Raize Components have a TRzFlowPanel UI component. Does exactly what you're after.
Use TRzFlowPanel to put an empty flow panel on a form. The major difference between a traditional panel and a flow panel is the way in which controls are placed. With a traditional panel, you place a control (such as a button) in a specific location. You can freely move that control to any location within the panel using the mouse. In a flow panel, each control is placed in a specific location, regardless of where you place it with the mouse. The automatic location is controlled by the FlowStyle property. For example, using the default FlowStyle property of LeftRightTopBottom, the first control you add to the flow panel snaps to the top left corner. The second control that you add snaps next to the first control, and so on.

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