Hello.
Currently the default behaviour of TCustomGrid is that when you click or
drag mouse cursor then the selected cell will become entirely visible by
scrolling the control. Sometimes even when the target cell is already fully
visible, the grid is scrolled in such a way that it "begins" with a full
column, i.e., not in the middle of the column. This is not desired behaviour
for me and I wanted to make an option to disable it.
Is it possible to do it without breaking compatibility with existing code?
I've attached the changes that I have made so far. I've added a
'goDisableScrollWithMouse' option that is disabled by default (as opposed to
'goScrollWithMouse' that would be enabled by default), so that current code
that didn't know about this option will continue to work correctly. I hope
this is enough.
What should I do with GRIDFILEVERSION? Do I have to increase to 4? It is
used in TCustomGrid.LoadContent to determine if the option value has to be
read (for example for goSmoothScroll). In the attached diff those are the
lines that are commented out.
Is it better to do it with a property/variable than a grid option?
--
cobines
Index: grids.pas
===================================================================
--- grids.pas (wersja 21126)
+++ grids.pas (kopia robocza)
@@ -103,7 +103,8 @@
goFixedRowNumbering, // Ya
goScrollKeepVisible, // keeps focused cell visible while scrolling
goHeaderHotTracking, // Header cells change look when mouse is over them
- goHeaderPushedLook // Header cells looks pushed when clicked
+ goHeaderPushedLook, // Header cells looks pushed when clicked
+ goDisableScrollWithMouse // Don't scroll to cell with mouse click or move
);
TGridOptions = set of TGridOption;
@@ -894,7 +895,7 @@
procedure MouseDown(Button: TMouseButton; Shift:TShiftState; X,Y:Integer); override;
procedure MouseMove(Shift: TShiftState; X,Y: Integer);override;
procedure MouseUp(Button: TMouseButton; Shift:TShiftState; X,Y:Integer); override;
- function MoveExtend(Relative: Boolean; DCol, DRow: Integer): Boolean;
+ function MoveExtend(Relative: Boolean; DCol, DRow: Integer; Scroll: Boolean): Boolean;
function MoveNextAuto(const Inverse: boolean): boolean;
function MoveNextSelectable(Relative:Boolean; DCol, DRow: Integer): Boolean;
procedure MoveSelection; virtual;
@@ -2438,7 +2439,7 @@
if AValue=FCol then Exit;
if not AllowOutboundEvents then
CheckLimitsWithError(AValue, FRow);
- MoveExtend(False, AValue, FRow);
+ MoveExtend(False, AValue, FRow, True);
Click;
end;
@@ -2447,7 +2448,7 @@
if AValue=FRow then Exit;
if not AllowOutBoundEvents then
CheckLimitsWithError(FCol, AValue);
- MoveExtend(False, FCol, AValue);
+ MoveExtend(False, FCol, AValue, True);
Click;
end;
@@ -5116,7 +5117,8 @@
Exit;
end;
- if not MoveExtend(False, FSplitter.X, FSplitter.Y) then begin
+ if not MoveExtend(False, FSplitter.X, FSplitter.Y,
+ not (goDisableScrollWithMouse in Options)) then begin
if EditorAlwaysShown then begin
SelectEditor;
EditorShow(true);
@@ -5152,7 +5154,7 @@
P:=MouseToLogcell(Point(X,Y));
if gfNeedsSelectActive in GridFlags then
SelectActive := (P.x<>FPivot.x)or(P.y<>FPivot.y);
- MoveExtend(False, P.x, P.y);
+ MoveExtend(False, P.x, P.y, not (goDisableScrollWithMouse in Options));
end;
gsColMoving:
@@ -5197,7 +5199,7 @@
gsSelecting:
begin
if SelectActive then
- MoveExtend(False, Cur.x, Cur.y)
+ MoveExtend(False, Cur.x, Cur.y, not (goDisableScrollWithMouse in Options))
else
CellClick(cur.x, cur.y);
end;
@@ -5780,7 +5782,7 @@
end;
end;
-function TCustomGrid.MoveExtend(Relative: Boolean; DCol, DRow: Integer): Boolean;
+function TCustomGrid.MoveExtend(Relative: Boolean; DCol, DRow: Integer; Scroll: Boolean): Boolean;
var
OldRange: TRect;
begin
@@ -5806,7 +5808,7 @@
end else
FRange:=NormalizarRect(Rect(Fpivot.x,FPivot.y, DCol, DRow));
- if not ScrollToCell(DCol, DRow) then
+ if (not Scroll) or (not ScrollToCell(DCol, DRow)) then
InvalidateMovement(DCol, DRow, OldRange);
SwapInt(DCol,FCol);
@@ -5879,7 +5881,7 @@
Inc(NRow, RInc);
SelOk:=SelectCell(NCol, NRow);
end;
- Result:=MoveExtend(False, NCol, NRow);
+ Result:=MoveExtend(False, NCol, NRow, True);
// whether or not a movement was valid if goAlwaysShowEditor
// is set, editor should pop up.
@@ -7015,6 +7017,7 @@
cfg.SetValue(Path+'goRelaxedRowSelect/value', goRelaxedRowSelect in options);
cfg.SetValue(Path+'goDblClickAutoSize/value', goDblClickAutoSize in options);
Cfg.SetValue(Path+'goSmoothScroll/value', goSmoothScroll in Options);
+ Cfg.SetValue(Path+'goDisableScrollWithMouse/value', goDisableScrollWithMouse in Options);
end;
Cfg.SetValue('grid/saveoptions/position', soPosition in SaveOptions);
@@ -7099,6 +7102,9 @@
if Version>=2 then begin
GetValue('goSmoothScroll',goSmoothScroll);
end;
+ //if Version >= 4 then begin
+ // GetValue('goDisableScrollWithMouse',goDisableScrollWithMouse);
+ //end;
Options:=Opt;
end;
@@ -7114,7 +7120,7 @@
j:=Cfg.GetValue('grid/position/row',-1);
if (i>=FFixedCols)and(i<=ColCount-1) and
(j>=FFixedRows)and(j<=RowCount-1) then begin
- MoveExtend(false, i,j);
+ MoveExtend(False, i, j, True);
end;
if goRangeSelect in Options then begin
FRange.left:=Cfg.getValue('grid/position/selection/left',FCol);
--
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