Wonderful Shell routines

delphi package - easy access to shell apis
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Logikmensch
Posts: 17
Joined: Fri Jun 30, 2006 4:26 am
Location: Germany

Wonderful Shell routines

Post by Logikmensch »

Hello members,

I'm very happy :D that I found the wonderful mad Collection, which is very easy to use, well-documented and in my case - for the madShell - the easiest way to handle the often strange Shell objects of the ShellAPI.
Indeed - I worked a lot to understand the concept of the shell routines, including CSIDL, PItemIDLists, etc., but the way the IShellObj interface can be used makes all these things understandable.
The only disadvantage is that the source is not included so I don't know *how* it works exactly, but that's the decision of the author. :wink:
Thanks for the great work!

Claus.
madshi
Site Admin
Posts: 10339
Joined: Sun Mar 21, 2004 5:25 pm

Post by madshi »

Thanks for the feedback!

The source code is of course included in the commercial edition... :wink:
Logikmensch
Posts: 17
Joined: Fri Jun 30, 2006 4:26 am
Location: Germany

Post by Logikmensch »

Yup. I already ordered the commercial version today. A good decision and not a waste of money. :D

Claus.
madshi
Site Admin
Posts: 10339
Joined: Sun Mar 21, 2004 5:25 pm

Post by madshi »

Thank you... :D
Logikmensch
Posts: 17
Joined: Fri Jun 30, 2006 4:26 am
Location: Germany

Memory allocation/disallocation when using ShellObj calls

Post by Logikmensch »

By the way:

when I use the structure

with ShellObj('c:\whatever.txt') do ...

the madshell Unit allocates a new Shell object for performing the action with the shell item 'c:\whatever.txt'. Is the structure correctly dis-allocated when a procedure / the application ends or Do I have to dis-allocate such objects for my own? I'm working on a Treeview routine made with ShellObj calls and I ask myself what about all those allocated shell items?
madshi
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Joined: Sun Mar 21, 2004 5:25 pm

Post by madshi »

madSecurity is based on reference counted interfaces. This works similar to how Delphi dynamic strings are working. Basically you don't need to care about freeing/destroying. It is done automatically.

I'd suggest that you complete your TreeView project and then afterwards use a tool like MemProof to make sure that there are no memory/resource leaks.
Logikmensch
Posts: 17
Joined: Fri Jun 30, 2006 4:26 am
Location: Germany

Post by Logikmensch »

Hi! :D You are very fast in replying.

Well, indeed, ShellObj frees the memory pretty much like using temporary strings. That's fascinating! All I have to do is to put anything I want to do with the ShellObj structure within the WITH context. Outside the with structure the object is already freed.

Allow me to publish the code of my testing tree view here (so other can see how easy madShell makes the stuff):

Code: Select all

unit Unit1;

interface

uses
  Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
  Dialogs, ComCtrls,  madshell;


type
  TForm1 = class(TForm)
    TreeView1: TTreeView;
    procedure TreeView1AdvancedCustomDrawItem(Sender: TCustomTreeView;
      Node: TTreeNode; State: TCustomDrawState; Stage: TCustomDrawStage;
      var PaintImages, DefaultDraw: Boolean);
    procedure TreeView1MouseUp(Sender: TObject; Button: TMouseButton;
      Shift: TShiftState; X, Y: Integer);
    procedure FormActivate(Sender: TObject);
    procedure FormCreate(Sender: TObject);
  private
    { Private-Deklarationen }
    first:boolean;
    procedure addnode(node:TTreeNode; ishell:IShellObj; var level:integer);
  public
    { Public-Deklarationen }
  end;

var
  Form1: TForm1;

implementation

{$R *.dfm}

procedure TForm1.addnode;
var
  i:integer;
begin
  inc(level);
  if ishell.isfolder then begin
    node:=TreeView1.Items.AddChild(node,ishell.name);
    if node<>nil then begin
      for i:=0 to ishell.ItemCount-1 do begin
        application.ProcessMessages;
        if level<3 then addnode(node,ishell.Items[i],level);
      end; {for}
    end; {if}
  end; {if}
  dec(level);
end;

procedure TForm1.FormCreate(Sender: TObject);
begin
  first:=true;
end;

procedure TForm1.FormActivate(Sender: TObject);
var
  level:integer;
begin
  level:=0;
  addnode(nil,shellobj('c:\'),level);
  first:=false;
end;

function getpath(node:TTreeNode):string;
begin
  result:='';
  if node<>nil then begin
    result:=node.Text;
    while node.parent<>nil do begin
      result:=node.Parent.Text+'\'+result;
      node:=node.Parent;
    end; {while}
    result:=stringreplace(result,'\\','\',[rfReplaceAll]);
  end; {if}
end;

procedure TForm1.TreeView1MouseUp(Sender: TObject; Button: TMouseButton;
  Shift: TShiftState; X, Y: Integer);
var
  node:TTreeNode;
  path:string;
begin
  if button=mbright then begin
    node:=TreeView1.GetNodeAt(x,y);
    path:=getpath(node);
    if path<>'' then shellobj(path).ShowContextMenu(handle);
  end; {if}
end;

procedure TForm1.TreeView1AdvancedCustomDrawItem(Sender: TCustomTreeView;
  Node: TTreeNode; State: TCustomDrawState; Stage: TCustomDrawStage;
  var PaintImages, DefaultDraw: Boolean);
var
  rect:TRect;
  icon:TIcon;
begin
  if node<>nil then begin
    rect:=node.DisplayRect(true);
    with treeview1.Canvas do begin
      brush.Color:=clYellow;
      brush.Style:=bsSolid;
      rect.Right:=rect.Right+16;
      textrect(rect,rect.Left+16+2,rect.Top+2,node.text);
      with ShellObj(getpath(node)) do begin
        icon:=TIcon.Create;
        icon.Handle:=geticon(16);
        draw(rect.Left,rect.Top,icon);
        icon.Free;
      end; {if}
    end; {with}
  end; {if}
end;

end.
Well, it's only a testing project - nothing real big. It only shows 2 levels of the tree - but you can right-click to get the explorer context menu.

Now I have to take some time to study what madShell definitely performs.
You have very high knowledge of the internal structures of the Shell (but not only), and of course you did that what the ShellAPI programmers did not: Making an understandable structured object for programmers. Thanks for that very good work! :D

Claus.
madshi
Site Admin
Posts: 10339
Joined: Sun Mar 21, 2004 5:25 pm

Post by madshi »

I'm glad you like it... :D
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