TFillStyle in Delphi’s VCL Windows UI toolkit indicates the type of color change that defines the boundary of a possibly non-rectangular region on a canvas.
TFillStyle values determine what type of color changes define the boundaries of a (possibly) non-rectangular region of a canvas, as indicated in the following table:
Value
Meaning
fsSurface
The region is defined…
ActionUpdateDelay property or DelphiVCL.Application.ActionUpdateDelay used to delay the call to DoActionIdle. This applies to native Windows development. The following example demonstrates the usefulness of this property:
Create an MDI project with the main form, an…
What is the DelphiVCL.Application.OnActionExecute Event?
The OnActionExecute or DelphiVCL.Application.OnActionExecute event occurs for Windows app development when an action’s Execute method is called and its action list has not already handled it.
Use the…
OnModalBegin or DelphiVCL.Application.ModalBegin occurs when a modal form is opened.
Write an OnModalBegin event handler to perform special processing when a modal form is opened.
How to examine the properties, methods, and built-in properties of the DelphiVCL.Application.OnModalBegin?
Let’s browse all the properties, methods, and built-in properties of the DelphiVCL.Application.OnModalBegin…
Whenever object-oriented programming is done in Python, then we will often come across the self method as their first parameter. This article explains the main concept of self method in Python for Windows development.
self represents the instance of the class in Python.
In Delphi VCL, TColor is used to specify the color of a control. It only works for development on Windows.
TColor is used to specify the color of a Windows-only control. It is used by the Color property of many components and by many other properties that specify color…
For Windows app development the BringToFront method or DelphiVCL.Application.BringToFront sets the last active window as the topmost window on the desktop above all other applications.
Use BringToFront to find the window owned by the MainForm that was last active and bring it to the foreground. BringToFront also tests to see if the window is visible and enabled before making it the topmost…
The ClassParent method or DelphiVCL.Application.ClassParent is used during Windows app development to return the type of the immediate ancestor of a class.
ClassParent returns the name of the parent class for an object instance or class reference. For TObject, ClassParent…
The Components property or DelphiVCL.Application.Components in Windows app development is used to list all components owned by the component. Of then this is used to programmatically iterate through all the components on a form or panel in order to update them in some…
The DelphiVCL CleanupInstance method or DelphiVCL.Application.CleanupInstance is used to perform finalization on long strings, variants, and interface variables within a class.
Do not call CleanupInstance directly. CleanupInstance is called automatically when the object instance is destroyed.
CleanupInstance releases all long strings and variants. It sets long strings to empty and variants…
