?
Solved

How can I change the order of the Items in a ListView by drag and drop?

Posted on 2004-04-09
2
Medium Priority
?
549 Views
Last Modified: 2010-04-05
Hi,

I'd like to change the order of the Items in a ListView just by drag and drop with the mouse?
Is this possible?


thanks
0
Comment
Question by:Bohne
[X]
Welcome to Experts Exchange

Add your voice to the tech community where 5M+ people just like you are talking about what matters.

  • Help others & share knowledge
  • Earn cash & points
  • Learn & ask questions
  • 2
2 Comments
 
LVL 11

Accepted Solution

by:
shaneholmes earned 500 total points
ID: 10791382
To drag items within a listview there are three things to do,
first set the dragmode in obect inspector to dmAutomatic.

In the OnDragOver event set the drag accept conditions, for example:

Procedure TForm1.ListView1DragOver(Sender, Source : TObject; X, Y :
Integer;
  State : TDragState; Var Accept : Boolean);
Begin
  Accept := (Source Is TListView)
        and (Source = Sender) // only accept from same  listview
End;

The list item manipulation code goes in the OnDragDrop event.
The following code will swap two items if one is dropped on the other
or put a dragged item at the end of the list if dropped on an empty
space.

Procedure TForm1.ListView1DragDrop(Sender, Source : TObject; X, Y :
Integer);
Var
  TargetItem, TempItem : TListItem;
Begin
  With TListView(Sender) Do
    Begin
      TempItem := items.add;
      TempItem.Assign(selected);
      TargetItem := GetItemAt(X, Y);
      If (TargetItem <> Nil) Then
        Begin
          selected.Assign(TargetItem);
          TargetItem.Assign(TempItem);
          TempItem.delete
        End
      Else
        selected.delete;
      Arrange(arAlignLeft)
    End;
End;

Shane
0
 
LVL 11

Expert Comment

by:shaneholmes
ID: 10791454
If you want to do it at runtime by a click of a button (btnUp, btnDown), then the code:

btnUp:

 if  ListView1.ItemIndex <> 0 then
begin
 ListView1.ItemIndex:= ListView1.ItemIndex - 1;
 ListView1.Items[ListView1.ItemIndex].Selected:= True;
 ListView1.Items[ListView1.ItemIndex].Focused:= True;
end;

btnDown:

if  ListView1.ItemIndex <> ListView1.Items.Count - 1  then
begin
 ListView1.ItemIndex:= ListView1.ItemIndex + 1;
 ListView1.Items[ListView1.ItemIndex].Selected:= True;
 ListView1.Items[ListView1.ItemIndex].Focused:= True;
end;


Shane
0

Featured Post

Free Tool: Port Scanner

Check which ports are open to the outside world. Helps make sure that your firewall rules are working as intended.

One of a set of tools we are providing to everyone as a way of saying thank you for being a part of the community.

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

Introduction The parallel port is a very commonly known port, it was widely used to connect a printer to the PC, if you look at the back of your computer, for those who don't have newer computers, there will be a port with 25 pins and a small print…
Creating an auto free TStringList The TStringList is a basic and frequently used object in Delphi. On many occasions, you may want to create a temporary list, process some items in the list and be done with the list. In such cases, you have to…
Michael from AdRem Software outlines event notifications and Automatic Corrective Actions in network monitoring. Automatic Corrective Actions are scripts, which can automatically run upon discovery of a certain undesirable condition in your network.…
In this video, Percona Director of Solution Engineering Jon Tobin discusses the function and features of Percona Server for MongoDB. How Percona can help Percona can help you determine if Percona Server for MongoDB is the right solution for …
Suggested Courses
Course of the Month11 days, 9 hours left to enroll

752 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question