Delphi’s TTabControl is a container type VCL control – allowing controls in its client area and displaying a set of tabs (as tabs or buttons). The TTabControl, unlike TPageControl, is not made up of several pages (for each tab), rather the TTabControl has one “page”. By design, the TTabControl is used when displaying/editing list of objects of the same type. When changing the active tab – you need to update the controls it hosts.
An example of a tabbed control UI is an Internet Browser – take a look at Chrome, IE, Edge, or Firefox, etc. tabs. See how each tab has a close button. No such similar close button, to “close a tab”, can be specified or set via properties or methods of the TTabControl. What if you need one (for whatever the purpose)?
So, how to implement a close button for a TTabControl’s Tab? Plus: how to display the close button only over the hot tab (under the mouse) and have the button nicely rounded.
“If you want it to be playable and more interesting you need to jazz it up a bit!”
That’s what’s been cooking in my head from the time I’ve finished implementing the back end for the game of Memory (Match Up, Concentration, or whatever you are used to call it). As a proof of concept, I’ve coded a very simple application, aka the front end for the game – juts to have a workable user interface.
Now, the time has come to finish the series and introduce a more eye candy version of the game, one that’s not using dull buttons with numbers for field display values but that actually looks like card game type of Memory, with nice fancy images/icons for game fields. Why stop there? Why not go a step forward and introduce a new dimension for the game: make it 3D having fields appear on planes/layers, so players need to switch between planes to match a pair.
In my previous post, Coding a Game of Memory in Delphi – OOP Model, I’ve been developing the model, aka the back end, for the Memory (Match Up, Concentration, …) game. The idea was to separate the game logic from the user interface (aka the front end). As a result a few classes were introduced: TPlayer, TField and, of course, the main class/object TMemoryGame implementing all the code required to run the game.
Having only the model does not help us much if we actually want to play the game. Therefore, this time, we go into building the user interface in Delphi.
Since the TMemoryGame class is framework agnostic (and not platform specific), it is up for you to decide if you would like to do a classic Windows VCL application, a FireMonkey Android mobile game or something that works on a Mac. To make it quick and simple, I’ll go old-style VCL school.
Looking for the best approach to change the background color (and other properties) of the focused data entry control in a Delphi (VCL) application?
By (Windows) design, the control on a data entry form which has the input focus is not drawn (/highlighted) differently from other controls (i.e. those without the input focus). In case of the TEdit (or TMemo and alike) control, only the blinking insertion point is displayed.
To provide visually more attractive user-friendly interfaces for your Delphi applications, you could decide to change the background color (and maybe some other properties) of the currently selected control – the one that has the input focus. Of course, this would include restoring to the original background color when the focus shifts to another control.