paweld/lazarus
1
0
Fork 0
mirror of https://gitlab.com/freepascal.org/lazarus/lazarus.git synced 2025-09-02 12:20:38 +02:00
Code Issues Packages Projects Releases Wiki Activity

Docs: LCL/forms. Updates TCustomForm.ActiveControl topic for changes in 16e2f677. Issue #40774.

Browse Source
This commit is contained in:
dsiders 2024-03-08 07:17:22 +00:00
parent d0869438b5
commit 888cfa910e
1 changed files with 27 additions and 10 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

37
docs/xml/lcl/forms.xml
View File

@ -7529,18 +7529,20 @@ already has focus when the active control is changed.
</element>
<element name="TCustomForm.ActiveControl">
<short>Specifies the active control on the form.</short>
<short>
Gets or sets the active control on the form.
</short>
<descr>
<p>
<var>ActiveControl</var> is a <var>TWinControl</var> property which contains
the control which has focus on the form. The property value can be <b>Nil</b>
if the form is hidden, disabled, or has never been activated.
the control which has focus on the form. The property can contain <b>Nil</b> if
the parent form is hidden, disabled, or has never been activated.
</p>
<p>
Setting a new value for the property causes validity checks to be performed
to ensure that the specified control can receive focus when the form is
<var>Visible</var>. An <var>EInvalidOperation</var> exception is raised when
the new property value contains:
Setting a new value for the property performs validity checks to ensure that
the specified control can receive focus when the form is <var>Visible</var>. An
<var>EInvalidOperation</var> exception is raised with the message in
SCannotFocus when the new property value contains:
</p>
<ul>
<li>The current form instance.</li>
@ -7548,15 +7550,30 @@ the new property value contains:
<li>A control that returns <b>False</b> from its CanFocus method.</li>
</ul>
<p>
The <var>SetWindowFocus</var> method is called if the form is
<var>Active</var>, and the <var>ActiveChanged</var> method is called.
The value in the LastActiveControl property is updated with the existing value
for ActiveControl if it is a control and not a TForm/TCustomForm instance. If
the form (and not a control) was active, LastActiveControl is set to <b>Nil</b>.
</p>
<p>
At run-time, the new active control is focused and activated if its form is
active (Active = <b>True</b>). ActiveChanged is called too. Both of these steps
are omitted at design-time or when the component is loaded during component
streaming.
</p>
<p>
The value in ActiveControl is updated in the <var>FocusControl</var> and
<var>DefocusControl</var> methods.
</p>
</descr>
<seealso/>
<seealso>
<link id="TCustomForm.LastActiveControl"/>
<link id="TCustomForm.Active"/>
<link id="TCustomForm.ActiveChanged"/>
<link id="TCustomForm.FocusControl"/>
<link id="TCustomForm.DefocusControl"/>
<link id="GetParentForm"/>
<link id="#lcl.controls.TWinControl.CanFocus"/>
</seealso>
</element>
<element name="TCustomForm.ActiveDefaultControl">