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Docs: LCL/forms. Updates the TApplication.CreateForm topic to match the order of operations after changes in 872608c3.

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dsiders 2023-09-15 03:52:36 +01:00
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docs/xml/lcl/forms.xml
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@ -15815,28 +15815,96 @@ Calls the AppBringToFront method in the widgetset class.
</element>
<element name="TApplication.CreateForm">
<short>Creates a Form or component, owned by Application.</short>
<short>
Creates a Form or component owned by the Application instance.
</short>
<descr>
<remark>
The method name is slightly misleading, and kept only for Delphi
compatibility. The method can actually create any kind of component.
</remark>
<p>
CreateForm creates a Component instance of the given class, and sets the
pointer to the component variable. If it is a form, it will be added to the
list of forms in the application.
<var>CreateForm</var> creates a new Component instance of the given class, and
sets the pointer to the component variable in <var>Reference</var>. If
InstanceClass is a TForm descendant, it will be added to the list of forms in
the application. It is assigned as the MainForm in Application if a form has
not already been assigned to the property. A form with its FormStyle property
set to fsMDIChild or fsSplash is not used as the MainForm for the Application.
</p>
<p>
A splash form is shown immediately.
If the new form instance is a splash form (FormStyle=fsSplash), it is displayed
immediately and a message processing loop is started for the form instance.
</p>
<p>
<b>Use in a .lpr Project File</b>
</p>
<p>
The most common use of CreateForm is in the project (.lpr) program file. It is
used to initialize the auto-created form instances for the project. For example:
</p>
<code>
program PoFileMaintenance;
{$mode objfpc}{$H+}
uses
{$IFDEF UNIX}
cthreads,
{$ENDIF}
{$IFDEF HASAMIGA}
athreads,
{$ENDIF}
Interfaces, Forms, PotFile, Unit1,
{ you can add units after this };
{$R *.res}
begin
RequireDerivedFormResource := True;
Application.Scaled := True;
Application.Initialize;
Application.CreateForm(TForm1, Form1);
Application.Run;
end.
</code>
<p>
<b>Use in Program Code</b>
</p>
<p>
Another common use of CreateForm is to allocate a dynamic, temporary form
instance as needed in program code. For example:
</p>
<code>
function ShowDialog(FormClass: TFormClass): Boolean;
var
Dlg: TForm;
begin
Application.CreateForm(FormClass, Dlg);
try
Result := Dlg.ShowModal in [mrOk, mrYes];
finally
Dlg.Free;
end;
end;
</code>
</descr>
<seealso/>
<seealso>
<link id="TApplication.MainForm"/>
<link id="TApplication.UpdateMainForm"/>
<link id="TApplication.ProcessMessages"/>
<link id="TCustomForm.FormStyle"/>
<link id="TCustomForm.Show"/>
</seealso>
</element>
<element name="TApplication.CreateForm.InstanceClass">
<short>The class type used to create the new instance.</short>
<short>
The class type used to create the new class instance.
</short>
</element>
<element name="TApplication.CreateForm.Reference">
<short>The variable for the new component reference.</short>
<short>
The output parameter used to return the new component reference.
</short>
</element>
<element name="TApplication.UpdateMainForm">