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#1: Scrollbars of simplegraph Author: P_G, Location: Germany

Posted: 02/08/04 11:07
—
Hi, Kambiz

Here's another idea for simplegraph: When you insert a couple of nodes and move them into negativ coordinates (the upper-left corner of the component), they are "lost", because no scrollbars appear. Of course you can mark all objects and move them by keyboard into your view. But for many users it would be a lot more comfortable, if scrollbars are shown for nodes with negativ coordinates too. Idea

C.U. P_G

#2: Author: Kambiz, Location: Tehran, Iran

Posted: 03/08/04 20:24
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I tried but I couldn't find an easy way to implement it. Sad

#3: Author: Kambiz, Location: Tehran, Iran

Posted: 04/08/04 07:23
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I added new FreezeTopLeft property to the TSimpleGraph's interface. When this property is True, the objects don't accept negative coordinates.

Cheers,
Kambiz

#4: Good workaround Author: P_G, Location: Germany

Posted: 04/08/04 20:14
—
Yip! That's a good way. Thank you, Kambiz. Wink

P_G

#5: Patch to enable scrolling beyond the topleft corner... Author: MeW, Location: Netherlands

Posted: 21/02/05 15:18
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I'm not sure if this would be a proper place to enter such a routine, but it seems to behave. Patch the method or create a subclass which overrides this method like this:

Code:

procedure TSimpleGraph.DoCanMoveResizeNode(Node: TGraphNode; var aLeft,
aTop, aWidth, aHeight: Integer; var CanMove, CanResize: Boolean);
var
i: integer;
Delta: TPoint;
R: TRect;
begin
if FreezeTopLeft then
begin
if aLeft < 0 then aLeft := 0;
if aTop < 0 then aTop := 0;
end
else
begin
{ MeW: scroll other nodes to the bottom right
if a node is scrolled beyond the topleft }
if (aLeft < Left) or (aTop < Top) then
begin
Delta := Point(0,0);
if (aLeft < Left) then Delta.X := -aLeft;
if (aTop < Top) then Delta.Y := -aTop;
BeginUpdate;
try
for i:=0 to ObjectsCount-1 do
begin
if (Objects.Items[i] <> Node) then
begin
R := Objects[i].BoundsRect;
OffsetRect(R, Delta.X, Delta.Y);
Objects[i].BoundsRect := R;
end;
end;
if (aLeft < Left) then aLeft := Left;
if (aTop < Top) then aTop := Top;
finally
EndUpdate;
end;
end;
end;
if Assigned(OnCanMoveResizeNode) then
OnCanMoveResizeNode(Self, Node, aLeft, aTop, aWidth, aHeight, CanMove, CanResize);
end;

#6: Author: Stefan, Location: Belgium, Antwerp

Posted: 21/02/05 16:35
—
Hello,

I've adjusted the code a little to get a little different behaviour, hope you don't mind Smile

Cheers,
Stefan

Code:

procedure TExtGraph.DoCanMoveResizeNode(Node: TGraphNode; var aLeft,
aTop, aWidth, aHeight: Integer; var CanMove, CanResize: Boolean);
var
i: integer;
Delta: TPoint;
R: TRect;
begin
if FreezeTopLeft then begin
if aLeft < 0 then aLeft := 0;
if aTop < 0 then aTop := 0;
end else begin
{ MeW: scroll other nodes to the bottom right if a node is scrolled beyond the topleft }
if (aLeft < 0) or (aTop < 0) then begin
Delta := Point(0,0);
if (aLeft < 0) then Delta.X := -aLeft;
if (aTop < 0) then Delta.Y := -aTop;
BeginUpdate;
try
for i:=0 to ObjectsCount-1 do
begin
if (Objects.Items[i] <> Node) then
begin
R := Objects[i].BoundsRect;
OffsetRect(R, Delta.X, Delta.Y);
Objects[i].BoundsRect := R;
end;
end;
if (aLeft < 0) then aLeft := 0;
if (aTop < 0) then aTop := 0;
finally
EndUpdate;
end;
end;
end;
if Assigned(OnCanMoveResizeNode) then
OnCanMoveResizeNode(Self, Node, aLeft, aTop, aWidth, aHeight, CanMove, CanResize);
end;

#7: Author: MeW, Location: Netherlands

Posted: 03/03/05 12:02
—
more enhancements are being prepared in the SourceForge project which also handles scrolling outside the bottomright corner...

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