DelphiVCL.PaintBox or TPaintBox provides a canvas that applications can use for rendering an image when you develop Windows software.
We can use TPaintBox to add custom images to a form. Unlike TImage, which displays an image that is stored in a bitmap, icon, or metafile, TPaintBox requires an application to draw the image directly on a canvas. Use the OnPaint event handler to draw on the paint…
This Is How TShiftState Works For Windows App Development
February 16, 2022
TShiftState in DelphiVCL indicates the state of the modifier keys – shift/ctrl/alt, the mouse buttons, or touch devices when you are performing Windows app development.
The TShiftState type is used by key-event and mouse-event handlers to determine the state of the…
DelphiVCL is a powerful framework for creating excellent, modern, graphical user interfaces (GUIs) for your Python programs. DelphiVCL is independent of Delphi and does not require Delphi to be installed. However, you can make use of Delphi’s powerful IDE software and its…
We use the Value property to set or specify any actions or parameters in the DelphiVCL library while using the IDE software.
Here is the working example of Value with CanSelect parameter:
def grdTestSelectCell(Sender, Col, Row, CanSelect):
if Col == 2 and Row == 2:
CanSelect.Value = False
In the example above, we set the CanSelect parameter to False to prevent the cell in…
The Lines Property contains the individual lines of text in the memo control. This works for native Windows development.
We use Lines to manipulate text in a memo control on a line-by-line basis. Lines is a DelphiVCL.Strings or TStrings object, so the TStrings methods may…
What Are Bi-Directional Properties In DelphiVCL Applications?
January 28, 2022
What is Bi-Directional (BiDi)?
Some languages do not follow the left to right reading order commonly found in Western languages, but rather use the right to left reading order for words and the left to right reading order for numbers. These languages are termed…
Everything You Need To Know About C++ ABI Inside DelphiVCL
January 27, 2022
C++ ABIs or more specifically: DelphiVCL.Application.CPP_ABI_1, DelphiVCL.Application.CPP_ABI_2, and DelphiVCL.Application.CPP_ABI_3 inside DelphiVCL.Application is C++ ABIs (Application Binary Interfaces, which are implemented under the hood, including how parameters are passed, such as in a register or on the stack).
In windows development software but also especially for Linux, an…
When you develop windows software use CreateForm method or DelphiVCL.Application.CreateForm to create a new form.
Call CreateForm to dynamically create a form at runtime. Developers do not need to add code for creating most forms, because typically one or more calls to…
For development on Windows OnGetMainFormHandle or DelphiVCL.Application.OnGetMainFormHandle is the event triggered when reading the value of the MainFormHandle property.
Let’s take a look at all of DelphiVCL.Application.OnGetMainFormHandle properties and…
What does the OnMessage Event in DelphiVCL.Application do?
January 24, 2022
In Windows application development the OnMessage or DelphiVCL.Application.OnMessage occurs when the application receives a message from either the Windows operating system or another application.
How to use the DelphiVCL.Application.OnMessage event properly?
We use the OnMessage to trap any or all Windows messages posted to all windows in the application. The OnMessage event occurs when an…
