The ComponentIndex property or DelphiVCL.Application.ComponentIndex from DelphiVCL is used to indicate the position of the component in its owner’s Components property array.
Use ComponentIndex when iterating through the Components list of the component’s owner to perform an action on owned components. It can be used in conjunction with ComponentCount. ComponentIndex is used…
Use the Dispatch method or DelphiVCL.Application.Dispatch from the DelphiVCL library to call message-handling methods for the object, based on the contents of the Message parameter.
Call Dispatch to automatically pass messages to the appropriate message…
The ComponentStyle property or DelphiVCL.Application.ComponentStyle is used to govern the behavior of the component when you are carrying out Windows development.
ComponentStyle governs how the component interacts with the streaming system and the Object Inspector.
The DoApplicationIdle method or DelphiVCL.Application.DoApplicationIdle is used to process messages in the Message queue for certain events as part of your Windows development.
The DoApplicationIdle method forces a call to the protected method TApplication.Idle. Idle triggers the event OnIdle, processes the events OnMouseEnter and OnMouseLeave, and updates the hints.
Let’s browse all the…
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…
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 MDI…
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 OnActionExecute event handler to respond when a user invokes actions whose action lists do not have OnExecute event…
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…
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…