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Docs: LCL/grids. Updates content in TCustomGrid.TrySmoothScrollBy and TCustomGrid.ScrollBy topics.

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dsiders 2023-09-29 01:21:08 +01:00
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commit b06ec95360
1 changed files with 96 additions and 16 deletions
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docs/xml/lcl/grids.xml
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@ -9235,17 +9235,6 @@ Indicates if the existing cursor shape is stored for later reuse.
</short>
</element>
<element name="TCustomGrid.TrySmoothScrollBy">
<short>
Scroll the grid origin by the specified relative columns and rows as needed.
</short>
<descr/>
<seealso/>
</element>
<element name="TCustomGrid.TrySmoothScrollBy.Result"/>
<element name="TCustomGrid.TrySmoothScrollBy.aColDelta"/>
<element name="TCustomGrid.TrySmoothScrollBy.aRowDelta"/>
<element name="TCustomGrid.TryScrollTo">
<short>
Attempts to scroll the grid until the specified coordinates are at the origin
@ -15643,17 +15632,29 @@ Scrolls the non-fixed area for the control by the specified delta values.
</short>
<descr>
<p>
Calls ScrollWindowEx to perform the scrolling operation for the non-fixed
client area in the control. No scrolling is performed when both DeltaX and
DeltaY contain 0 (zero).
<var>ScrollBy</var> us an overridden method in <var>TCustomGrid</var>. No
actions are performed in the method when both DeltaX and DeltaY contain 0
(zero).
</p>
<p>
Updates the visible grid area in the cached information for the control, and
recalculates the scroll bar ranges.
ScrollBy calls ScrollWindowEx to perform the scrolling operation for the
non-fixed client area on the control. It updates the visible grid area in the
cached information for the control, and recalculates the scroll bar ranges.
</p>
<p>
ScrollBy is called from the TrySmoothScrollBy method, and occurs when scroll
bar messages or mouse wheel events are handled for the grid control.
</p>
</descr>
<seealso>
<link id="TCustomGrid.FixedCols"/>
<link id="TCustomGrid.FixedRows"/>
<link id="TCustomGrid.TrySmoothScrollBy"/>
<link id="TCustomGrid.LeftCol"/>
<link id="TCustomGrid.TopRow"/>
<link id="TCustomGrid.GridMouseWheel"/>
<link id="#lcl.controls.TWinControl.ScrollBy">TWinControl.ScrollBy</link>
<link id="#lcl.controls.TControl.ClientRect">TControl.ClientRect</link>
</seealso>
</element>
<element name="TCustomGrid.ScrollBy.DeltaX">
@ -16174,6 +16175,85 @@ Row offset or number for the selection.
</short>
</element>
<element name="TCustomGrid.TrySmoothScrollBy">
<short>
Scrolls the grid origin by the specified relative amounts.
</short>
<descr>
<p>
<var>TrySmoothScrollBy</var> is an <var>Integer</var> function used to scroll
the grid control by the specified horizontal and vertical amounts (Deltas).
TrySmoothScrollBy ensures that the internal cache for the control is updated to
reflect the visible area for the control after the scroll operation.
</p>
<p>
TrySmoothScrollBy is called from methods that handle scroll bar or the event
handler for mouse wheel messages, and occurs when the user interacts with the
the grid control. For example: WMHScroll, WMVScroll, and GridMouseWheel. In is
not intended for use in end-user code - but it's not expressly forbidden either.
</p>
<p>
<var>AColDelta</var> and <var>ARowDelta</var> contain the number of pixels that
the control content should be scrolled in the horizontal and vertical
directions. Positive values indicate that the content should scroll towards the
right or bottom of the control. Negative values indicate that the content
should scroll towards the left or top of the control.
</p>
<p>
No actions are performed in the method when both AColDelta and ARowDelta are
set to 0 (zero).
</p>
<p>
TrySmoothScrollBy uses the coordinates for the visible cell at the top and left
coordinates on the control for the scroll operation. It also uses values in
ColWidths and RowHeights to determine when a cells become visible (or hidden)
on the control canvas and in its cache. When goScrollKeepVisible has been
included in Options, the selection on the control is extended to include the
scrolled area. The ScrollBy method is called using the calculated X and Y
offsets for the new top and left coordinates on the control.
</p>
<p>
The return value is <b>True</b> if the scroll operation was successfully
completed in the method. The return value is <b>False</b> if the operation
failed due to cell that is too tall or too wide for the requested scroll
value(s). This can occur when goSmoothScroll is <b>not</b> included in the grid
Options.
</p>
</descr>
<version>
Modified in LCL version 4.0 to have protected visibility.
</version>
<seealso>
<link id="TCustomGrid.ColWidths"/>
<link id="TCustomGrid.GCache"/>
<link id="TCustomGrid.GetPxTopLeft"/>
<link id="TCustomGrid.GetSmoothScroll"/>
<link id="TCustomGrid.GridMouseWheel"/>
<link id="TCustomGrid.MoveNextSelectable"/>
<link id="TCustomGrid.Options"/>
<link id="TCustomGrid.RowHeights"/>
<link id="TCustomGrid.ScrollBy"/>
<link id="TCustomGrid.TopLeftChanged"/>
<link id="TCustomDrawGrid.GridMouseWheel"/>
<link id="TGridOption"/>
</seealso>
</element>
<element name="TCustomGrid.TrySmoothScrollBy.Result">
<short>
<b>True</b> on successful completion of the scroll operation.
</short>
</element>
<element name="TCustomGrid.TrySmoothScrollBy.aColDelta">
<short>
Indicates the direction and number of pixels for a horizontal scroll request.
</short>
</element>
<element name="TCustomGrid.TrySmoothScrollBy.aRowDelta">
<short>
Indicates the direction and number of pixels for a vertical scroll request.
</short>
</element>
<element name="TCustomGrid.UnLockEditor">
<short>
Decrements the lock count for the cell Editor following a call to LockEditor.