[Webinar] Streamline your web hosting managementRegister Today

x
  • Status: Solved
  • Priority: Medium
  • Security: Public
  • Views: 486
  • Last Modified:

Delphi 7 :: Programmatically adjust TListView height to display all items

Dear Experts,

I have an TListView where each item added respresents a file (and the file's associated icon).
All is working great.

As new items are added to the ListView I would like to determine if all items fit the
display size and if not then I want to increase the height of the ListView to display all items without
showing the scrollbars.

Hope this is clear.

Thanks!
0
Marius0188
Asked:
Marius0188
  • 5
  • 4
1 Solution
 
TheRealLokiSenior DeveloperCommented:
something like this?

procedure TForm1.Button1Click(Sender: TObject);
var
  newitem: TListitem;
  requiredsize: integer;
  tm: tagTEXTMETRIC;
  newcount: integer;
begin
  ListView1.ViewStyle := vsreport;

  newcount := ListView1.Items.Count + 1; // we are going to add an item
  GetTextMetrics(Listview1.Canvas.Handle, tm);
  requiredsize := (newcount) * (tm.tmHeight + 1);
  requiredsize := 12 + tm.tmHeight + requiredsize; // room for border and header + (height per line)
  listview1.height := requiredsize;
// now add the item - adding after resizing so that scrollbars dont try to appear
  newitem := ListView1.Items.Add;
  newitem.caption := edit1.text;
end;
0
 
Marius0188Author Commented:
Close but not exactly working.

Everytime I add a new item the listviews height grows even
when not necessary.

0
 
Marius0188Author Commented:
Sorry I should of mentioned:

That I need it be:

ListView.ViewStyle := vsSmallIcon
0
Keep up with what's happening at Experts Exchange!

Sign up to receive Decoded, a new monthly digest with product updates, feature release info, continuing education opportunities, and more.

 
TheRealLokiSenior DeveloperCommented:
ahhh i see, ok

procedure TForm1.Button2Click(Sender: TObject);
var
  newitem: TListitem;
  i: integer;
  maxw, maxh: integer;
  itemrect: TRect;
begin
    newitem := ListView1.Items.Add;
    newitem.caption := edit1.text;
    newitem.ImageIndex := random(3);
    maxh := 0;
    maxw := 0;
    for i := 0 to pred(listview1.items.count) do
    begin
      itemrect := ListView1.Items[i].DisplayRect(drBounds);
      maxw := max(maxw, itemrect.Left + (itemrect.Right - itemrect.Left));
      maxh := max(maxh, itemrect.Top + (itemrect.Bottom - itemrect.Top));
    end;
    ListView1.height := 6 + maxh;
end;
0
 
TheRealLokiSenior DeveloperCommented:
add "uses math;" for the "max()" function
0
 
Marius0188Author Commented:
Its better and closer but still.

But still when adding to 2 filenames as items caption then it sqeezes both in "one line" instead of rather checking what is the ListView current Height and determine if it enough else increase the height of the ListView and insert new item in "second row".

Thanks for helping so far :)
0
 
TheRealLokiSenior DeveloperCommented:
I'm sorry, i don't quite understand. do you have some example code or can you explain it a little more to me thanks.
0
 
TheRealLokiSenior DeveloperCommented:
actually, I think I know what you mean. Try this one

procedure TForm1.Button3Click(Sender: TObject);
var
  newitem: TListitem;
begin
  newitem := ListView1.Items.Add;
  inc(uniquenumber);
  newitem.caption := edit1.text;
  RearrangeListViewIconsAndHeight;
end;

procedure TForm1.RearrangeListViewIconsAndHeight;
var
  newitem: TListitem;
  i: integer;
  maxw, maxh: integer;
  itemrect: TRect;
  newpos: tpoint;
  currentx, currenty: integer;
  itemsinthisrow: integer;
  lvdisplaywidth: integer;
begin
    maxh := 0;
    maxw := 0;
    lvdisplaywidth := Listview1.Width - 2;
    itemsinthisrow := 0;
    currentx := 0;
    currenty := 0;
    for i := 0 to pred(listview1.items.count) do
    begin
      itemrect := ListView1.Items[i].DisplayRect(drBounds);
      if (currentx + (itemrect.Right - itemrect.Left)) > lvdisplaywidth then
      begin  // goes outide of bounds, move down if possible
        currentx := 0;
        newpos.x := 0;
        currenty := currenty + (itemrect.Bottom - itemrect.Top); // assume same "height" for all icons
        newpos.y := currenty;
        itemsinthisrow := 0;
      end
      else
      begin
        inc(itemsinthisrow);
        newpos.x := currentx;
        newpos.y := currenty;
      end;
      ListView1.Items[i].SetPosition(newpos);
      currentx := currentx + (itemrect.Right - itemrect.Left);
      maxw := max(maxw, currentx);
      maxh := max(maxh, currenty + (itemrect.Bottom - itemrect.Top));
    end;
    ListView1.height := 6 + maxh;
end;
0
 
Marius0188Author Commented:
I have tried your last suggestion.
Looks like the one I need.

So far so good.
Wil let you know as soon I have implement it.

Thanks!
0

Featured Post

Take Control of Web Hosting For Your Clients

As a web developer or IT admin, successfully managing multiple client accounts can be challenging. In this webinar we will look at the tools provided by Media Temple and Plesk to make managing your clients’ hosting easier.

  • 5
  • 4
Tackle projects and never again get stuck behind a technical roadblock.
Join Now