Drag and Drop Rectangle... How to go about it?

[mountfranklin]

Hi again.

I would like to know the simplest way to implement a drag and drop feature for my rectangles I draw up.

I can select the rectangles and I know I have to get the old position to equal the new position but wouldn't know how to actually do this.

I would think that I would have to put it into MouseMove but again, not sure.

Any help would be awesome, cheers

[WRoos]

I know about Drag/Drop to use for contents of a control (maybe a certain line in a listbox)to Drag to another control, or Drag the total control to a different location.

If you drawn a rectangle on a form, and want it to be somewhere else it is easiest to erase the first one, then draw it on the new position again.
You could try "Canvas->Pen->Mode = pmXor;" while drawing your rectangle. This is special, because it inverts the color. You can restore it by simply draw it again.
In your .h you can declare a rect:ARect and a boolean Moving.
In FormCreate-Event draw your first rect and save it in ARect. Also set Moving to false;

In MouseDown-Event set Moving to true.
In MouseUp-Event set Moving to false.
In MouseMove-Event: if (Moving)you first draw the old-position to erase, then calculate the new position and draw it there.
save new position in ARect.

Good-Luck