Unit containing its own form
lazarus / 21-General

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torbente · 2021-01-26 08:42

I coded a simple file explorer (image included)
Then i try to make an unit from it.

Code: Pascal  [Select][+][-]window.onload = function(){var x1 =
document.getElementById("main_content_section"); if (x1) { var x =
document.getElementsByClassName("geshi");for (var i = 0; i unit
FormExplore; {$mode objfpc}{$H+} interface uses  Classes, SysUtils,
forms, controls, stdctrls,Graphics, buttons, grids, fileutil; function
OnlyName(conpath:string):string;procedure FGridFilesDblClick(Sender:
TObject);Procedure LoadDirectory(directory:string);procedure
FSBUpPathClick(Sender: TObject);Procedure
ShowExplorer(Directory:string); var  FExplorer : TForm;  EditPath :
Tedit;  FSBUpPath : TSpeedButton;  FGridFiles : TStringGrid; 
FEditFilename : Tedit;  FSBOkFile : TSpeedButton;   FActiveDir :
String = '';  FilesDir : TStringList;  FoldersDir : TStringList; 
Result : String = ''; implementation Procedure ShowExplorer(Directory:
String);BeginLoadDirectory(Directory);FExplorer.Visible:=true;End; fun
ction OnlyName(conpath:string):string;var  cont : integer;Beginfor
cont := length(conpath) downto 1 do   if conpath[cont] = '\' then    
begin      result := copy(conpath,cont+1,length(conpath));     
break;      end;end; procedure FSBUpPathClick(Sender: TObject);var 
contador : integer;beginfor contador := length(FActiveDir) downto 1
do   begin   if FActiveDir[contador] = '\' then      begin     
FActiveDir := copy(FActiveDir,1,contador-1);     
LoadDirectory(FActiveDir);      break      end;   end;end; procedure
FGridFilesDblClick(Sender: TObject);beginif FGridFiles.Row>0 then 
 begin   if copy(FGridFiles.Cells[0,FGridFiles.Row],1,3) = '   ' then 
    begin      FActiveDir := FActiveDir+'\'+ copy(FGridFiles.Cells[0,F
GridFiles.Row],4,length(FGridFiles.Cells[0,FGridFiles.Row]));     
LoadDirectory(FActiveDir);      end;   end;end; procedure
FGridFilesSelection(Sender: TObject; aCol, aRow: Integer);beginFEditFi
lename.Text:=FGridFiles.Cells[0,FGridFiles.Row];if
copy(FEditFilename.Text,1,3)='   ' then
FEditFilename.Text:='';end; Procedure
LoadDirectory(directory:string);var  cont : integer;BeginFilesDir.Clea
r;FoldersDir.clear;FGridFiles.RowCount:=1;FindAllFiles(FilesDir,
directory, '*.*', false);FoldersDir :=
FindAllDirectories(directory,false);if FoldersDir.Count>0 then 
 Begin   for cont := 0 to FoldersDir.Count-1 do      begin     
FGridFiles.RowCount:=FGridFiles.RowCount+1;     
FGridFiles.Cells[0,cont+1]:='   '+OnlyName(FoldersDir[cont]);     
end;   end;if FilesDir.Count>0 then   begin   for cont := 0 to
FilesDir.Count-1 do      begin     
FGridFiles.RowCount:=FGridFiles.RowCount+1;     
FGridFiles.Cells[0,FGridFiles.RowCount-1]:=OnlyName(FilesDir[cont]); 
   end;   end;EditPath.Text:=directory;End; beginFExplorer :=
TForm.Create(nil);FExplorer.caption := 'File
Explorer';FExplorer.SetBounds(0, 0, 450, 350);FExplorer.BorderStyle :=
bssingle;FExplorer.Position:=poOwnerFormCenter;FExplorer.BorderIcons:=
FExplorer.BorderIcons-[biminimize]; EditPath := TEdit.Create(FExplorer
);EditPath.Parent:=FExplorer;EditPath.AutoSize:=false;EditPath.Left:=1
;EditPath.Top:=1;EditPath.Height:=24;EditPath.Width:=424;EditPath.Font
.Name:='consolas'; EditPath.Font.Size:=12;EditPath.Color:=clBlack;Edit
Path.Font.color:=clwhite;EditPath.Alignment:=taLeftJustify;EditPath.Vi
sible:=true;EditPath.Enabled:=true;EditPath.ReadOnly:=true; FSBUpPath
:= TSpeedButton.Create(FExplorer);FSBUpPath.Parent:=FExplorer;FSBUpPat
h.Left:=426;FSBUpPath.Top:=2;FSBUpPath.Height:=22;FSBUpPath.Width:=22;
FSBUpPath.Visible:=true;FSBUpPath.hint:='Go up';FSBUpPath.ShowHint:=tr
ue;//FSBUpPath.OnClick:=SBUpPathClick; FGridFiles := TStringGrid.Creat
e(nil);FGridFiles.Parent:=FExplorer;FGridFiles.Font.Name:='consolas';
FGridFiles.Font.Size:=12;FGridFiles.Left:=2;FGridFiles.Top:=24;FGridFi
les.Height:=298;FGridFiles.width:=446;FGridFiles.FixedCols:=0;FGridFil
es.FixedRows:=1;FGridFiles.rowcount := 1;FGridFiles.ColCount:=4;FGridF
iles.ScrollBars:=ssAutoVertical;FGridFiles.Options:=
FGridFiles.Options-[goRangeSelect];FGridFiles.ColWidths[0]:=
444;FGridFiles.Cells[0,0]:= 'Name';FGridFiles.FocusRectVisible:=false;
//FGridFiles.OnDblClick:=FGridFilesDblClick;//FGridFiles.OnSelection:=
FGridFilesSelection; FEditFilename := TEdit.Create(FExplorer);FEditFil
ename.Parent:=FExplorer;FEditFilename.AutoSize:=false;FEditFilename.Le
ft:=1;FEditFilename.Top:=324;FEditFilename.Height:=24;FEditFilename.Wi
dth:=384;FEditFilename.Font.Name:='consolas'; FEditFilename.Font.Size:
=12;FEditFilename.Color:=clBlack;FEditFilename.Font.color:=clwhite;FEd
itFilename.Alignment:=taLeftJustify;FEditFilename.Visible:=true;FEditF
ilename.Enabled:=true;FEditFilename.ReadOnly:=true; FSBOkFile := TSpee
dButton.Create(FExplorer);FSBOkFile.Parent:=FExplorer;FSBOkFile.Left:=
388;FSBOkFile.Top:=324;FSBOkFile.Height:=22;FSBOkFile.Width:=60;FSBOkF
ile.Visible:=true;FSBOkFile.hint:='Accept';FSBOkFile.ShowHint:=true;//
FSBOkFile.OnClick:=@form1.FSBOkFileOnClick; FilesDir :=
TStringList.Create;FoldersDir := TStringList.Create;END.  
But im missing something since im unable to assign the event functions
to its controls.
(lines 129,141,142,155)

PS: The unit is still not finished, but im stuck here. It actually
works but without control events, it is impossible to navigate.

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dseligo · 2021-01-26 09:23

I think that event procedures should be part of class (method). So,
try to create a class and put this procedures in that class.

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howardpc · 2021-01-26 10:05

something like this:
Code: Pascal  [Select][+][-]window.onload = function(){var x1 =
document.getElementById("main_content_section"); if (x1) { var x =
document.getElementsByClassName("geshi");for (var i = 0; i unit
FormExplore; {$mode objfpc}{$H+} interface uses  Classes, SysUtils,
FileUtil,  Forms, Controls, StdCtrls, Graphics, Buttons, Grids; type 
TExplorerForm = class(TForm)  private    EditPath: TEdit;   
FActiveDir: String;    FEditFilename: TEdit;    FGridFiles:
TStringGrid;    FilesDir: TStringList;    FoldersDir: TStringList;   
FSBOkFile: TSpeedButton;    FSBUpPath: TSpeedButton;      procedure
FSBOkFileOnClick(Sender: TObject);    function OnlyName(const conpath:
String): String;    procedure FGridFilesDblClick(Sender: TObject);   
procedure FGridFilesSelection(Sender: TObject; aCol, aRow: Integer); 
 procedure SBUpPathClick(Sender: TObject);    procedure
LoadDirectory(const Directory: String);  public    constructor
Create(TheOwner: TComponent); override;    destructor Destroy;
override;  end;   procedure ShowExplorer(const Directory:
String); implementation var  explorer: TExplorerForm = Nil; procedure
ShowExplorer(const Directory: String); begin  if not
Assigned(explorer) then    explorer := TExplorerForm.Create(Nil); 
explorer.LoadDirectory(Directory);  explorer.Show;end; { TExplorerForm
} constructor TExplorerForm.Create(TheOwner: TComponent);begin 
inherited CreateNew(TheOwner);  Caption := 'File Explorer'; 
SetBounds(0, 0, 450, 350);  BorderStyle := bssingle;  Position :=
poOwnerFormCenter;  BorderIcons := BorderIcons - [biminimize];  
FilesDir := TStringList.Create;  FoldersDir := TStringList.Create;  
EditPath := TEdit.Create(Self);  with EditPath do    begin     
SetBounds(1, 1, 424, 24);      Font.Name := 'consolas';      Font.Size
:= 12;      Font.Color := clWhite;      Color := clBlack;     
Alignment := taLeftJustify;      ReadOnly := True;      Parent :=
Self;    end;   FSBUpPath := TSpeedButton.Create(Self);  with
FSBUpPath do    begin      SetBounds(426, 2, 22, 22);      Hint := 'Go
up';      ShowHint := True;      OnClick := @SBUpPathClick;     
Parent := Self;    end;   FGridFiles := TStringGrid.Create(Self); 
with FGridFiles do    begin      SetBounds(2, 24, 446, 298);     
Font.Name := 'consolas';      Font.Size := 12;      FixedCols := 0;  
  FixedRows := 1;      RowCount := 1;      ColCount := 4;     
ScrollBars := ssAutoVertical;      Options := Options -
[goRangeSelect];      ColWidths[0] := 444;      Cells[0,0] := 'Name'; 
    FocusRectVisible := False;      OnDblClick :=
@FGridFilesDblClick;      OnSelection := @FGridFilesSelection;     
Parent := Self;    end;   FEditFilename := TEdit.Create(Self);  with
FEditFilename do    begin      SetBounds(1, 324, 384, 24);     
AutoSize := False;      Font.Name := 'consolas';      Font.Size :=
12;      Font.Color := clWhite;      Color := clBlack;      Alignment
:= taLeftJustify;      ReadOnly := True;      Parent := Self;   
end;   FSBOkFile := TSpeedButton.Create(Self);  with FSBOkFile do   
begin      SetBounds(388, 324, 60, 22);      ShowHint := True;     
Hint := 'Accept';      OnClick := @FSBOkFileOnClick;      Parent :=
Self;    end; end; destructor TExplorerForm.Destroy;begin 
FilesDir.Free;  FoldersDir.Free;  inherited Destroy;end; procedure
TExplorerForm.FGridFilesDblClick(Sender: TObject);begin  if
(FGridFiles.Row > 0) and (Copy(FGridFiles.Cells[0,FGridFiles.Row],1,3)
= '   ' ) then    begin      FActiveDir := FActiveDir+'\'+ Copy(FGridF
iles.Cells[0,FGridFiles.Row],4,Length(FGridFiles.Cells[0,FGridFiles.Ro
w]));      LoadDirectory(FActiveDir);   end;end; procedure
TExplorerForm.FGridFilesSelection(Sender: TObject; aCol, aRow:
Integer);begin  FEditFilename.Text :=
FGridFiles.Cells[0,FGridFiles.Row];  if Copy(FEditFilename.Text,1,3) =
'   ' then    FEditFilename.Text := '';end; procedure
TExplorerForm.FSBOkFileOnClick(Sender: TObject);begin  // your code
hereend; procedure TExplorerForm.LoadDirectory(const Directory:
String);var  cont: Integer;begin  FilesDir.Clear;  FoldersDir.Clear; 
FGridFiles.RowCount := 1;  FindAllFiles(FilesDir, Directory, '*.*',
False);  FindAllDirectories(FoldersDir, Directory, False);  if
FoldersDir.Count > 0 then    for cont := 0 to FoldersDir.Count-1 do  
  begin        FGridFiles.RowCount := FGridFiles.RowCount+1;       
FGridFiles.Cells[0,cont+1] := '   ' + OnlyName(FoldersDir[cont]);    
end;  if FilesDir.Count > 0 then    for cont := 0 to FilesDir.Count-1
do      begin        FGridFiles.RowCount := FGridFiles.RowCount+1;   
   FGridFiles.Cells[0,FGridFiles.RowCount-1] :=
OnlyName(FilesDir[cont]);      end;  EditPath.Text :=
Directory;end; function TExplorerForm.OnlyName(const conpath: String):
String;var  cont: Integer;begin  for cont := Length(conpath) downto 1
do   if conpath[cont] = '\' then     begin       Result :=
Copy(conpath, cont+1, Length(conpath));       Break;   
 end;end; procedure TExplorerForm.SBUpPathClick(Sender: TObject);var 
contador : integer;beginfor contador := length(FActiveDir) downto 1
do   begin   if FActiveDir[contador] = '\' then      begin       
FActiveDir := copy(FActiveDir,1,contador-1);       
LoadDirectory(FActiveDir);        Break;      end; 
 end;end; finalization   explorer.Free;  explorer := Nil; end.

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torbente · 2021-01-26 13:26

Your code works perfect! Thanks a lot. I did not have idea i need
declare a new class for the form.

Actually, when ok button is pressed, it returns the full path showed
in the upper Tedit+'\'+Name of the file specified.
The string is exactly the same i got from the windows file explorer.
But if i apply a Fileexists to this string, i get a false  .
I guest it is something with the application dir, but it not supposed
that with the complete path it should work?
I try changing the directory separator from '\' to '/' but it did not
work  neither

Quote from: howardpc on January 26, 2021, 11:05:32 amsomething like
this:
Code: Pascal  [Select][+][-]window.onload = function(){var x1 =
document.getElementById("main_content_section"); if (x1) { var x =
document.getElementsByClassName("geshi");for (var i = 0; i unit
FormExplore; {$mode objfpc}{$H+} interface uses  Classes, SysUtils,
FileUtil,  Forms, Controls, StdCtrls, Graphics, Buttons, Grids; type 
TExplorerForm = class(TForm)  private    EditPath: TEdit;   
FActiveDir: String;    FEditFilename: TEdit;    FGridFiles:
TStringGrid;    FilesDir: TStringList;    FoldersDir: TStringList;   
FSBOkFile: TSpeedButton;    FSBUpPath: TSpeedButton;      procedure
FSBOkFileOnClick(Sender: TObject);    function OnlyName(const conpath:
String): String;    procedure FGridFilesDblClick(Sender: TObject);   
procedure FGridFilesSelection(Sender: TObject; aCol, aRow: Integer); 
 procedure SBUpPathClick(Sender: TObject);    procedure
LoadDirectory(const Directory: String);  public    constructor
Create(TheOwner: TComponent); override;    destructor Destroy;
override;  end;   procedure ShowExplorer(const Directory:
String); implementation var  explorer: TExplorerForm = Nil; procedure
ShowExplorer(const Directory: String); begin  if not
Assigned(explorer) then    explorer := TExplorerForm.Create(Nil); 
explorer.LoadDirectory(Directory);  explorer.Show;end; { TExplorerForm
} constructor TExplorerForm.Create(TheOwner: TComponent);begin 
inherited CreateNew(TheOwner);  Caption := 'File Explorer'; 
SetBounds(0, 0, 450, 350);  BorderStyle := bssingle;  Position :=
poOwnerFormCenter;  BorderIcons := BorderIcons - [biminimize];  
FilesDir := TStringList.Create;  FoldersDir := TStringList.Create;  
EditPath := TEdit.Create(Self);  with EditPath do    begin     
SetBounds(1, 1, 424, 24);      Font.Name := 'consolas';      Font.Size
:= 12;      Font.Color := clWhite;      Color := clBlack;     
Alignment := taLeftJustify;      ReadOnly := True;      Parent :=
Self;    end;   FSBUpPath := TSpeedButton.Create(Self);  with
FSBUpPath do    begin      SetBounds(426, 2, 22, 22);      Hint := 'Go
up';      ShowHint := True;      OnClick := @SBUpPathClick;     
Parent := Self;    end;   FGridFiles := TStringGrid.Create(Self); 
with FGridFiles do    begin      SetBounds(2, 24, 446, 298);     
Font.Name := 'consolas';      Font.Size := 12;      FixedCols := 0;  
  FixedRows := 1;      RowCount := 1;      ColCount := 4;     
ScrollBars := ssAutoVertical;      Options := Options -
[goRangeSelect];      ColWidths[0] := 444;      Cells[0,0] := 'Name'; 
    FocusRectVisible := False;      OnDblClick :=
@FGridFilesDblClick;      OnSelection := @FGridFilesSelection;     
Parent := Self;    end;   FEditFilename := TEdit.Create(Self);  with
FEditFilename do    begin      SetBounds(1, 324, 384, 24);     
AutoSize := False;      Font.Name := 'consolas';      Font.Size :=
12;      Font.Color := clWhite;      Color := clBlack;      Alignment
:= taLeftJustify;      ReadOnly := True;      Parent := Self;   
end;   FSBOkFile := TSpeedButton.Create(Self);  with FSBOkFile do   
begin      SetBounds(388, 324, 60, 22);      ShowHint := True;     
Hint := 'Accept';      OnClick := @FSBOkFileOnClick;      Parent :=
Self;    end; end; destructor TExplorerForm.Destroy;begin 
FilesDir.Free;  FoldersDir.Free;  inherited Destroy;end; procedure
TExplorerForm.FGridFilesDblClick(Sender: TObject);begin  if
(FGridFiles.Row > 0) and (Copy(FGridFiles.Cells[0,FGridFiles.Row],1,3)
= '   ' ) then    begin      FActiveDir := FActiveDir+'\'+ Copy(FGridF
iles.Cells[0,FGridFiles.Row],4,Length(FGridFiles.Cells[0,FGridFiles.Ro
w]));      LoadDirectory(FActiveDir);   end;end; procedure
TExplorerForm.FGridFilesSelection(Sender: TObject; aCol, aRow:
Integer);begin  FEditFilename.Text :=
FGridFiles.Cells[0,FGridFiles.Row];  if Copy(FEditFilename.Text,1,3) =
'   ' then    FEditFilename.Text := '';end; procedure
TExplorerForm.FSBOkFileOnClick(Sender: TObject);begin  // your code
hereend; procedure TExplorerForm.LoadDirectory(const Directory:
String);var  cont: Integer;begin  FilesDir.Clear;  FoldersDir.Clear; 
FGridFiles.RowCount := 1;  FindAllFiles(FilesDir, Directory, '*.*',
False);  FindAllDirectories(FoldersDir, Directory, False);  if
FoldersDir.Count > 0 then    for cont := 0 to FoldersDir.Count-1 do  
  begin        FGridFiles.RowCount := FGridFiles.RowCount+1;       
FGridFiles.Cells[0,cont+1] := '   ' + OnlyName(FoldersDir[cont]);    
end;  if FilesDir.Count > 0 then    for cont := 0 to FilesDir.Count-1
do      begin        FGridFiles.RowCount := FGridFiles.RowCount+1;   
   FGridFiles.Cells[0,FGridFiles.RowCount-1] :=
OnlyName(FilesDir[cont]);      end;  EditPath.Text :=
Directory;end; function TExplorerForm.OnlyName(const conpath: String):
String;var  cont: Integer;begin  for cont := Length(conpath) downto 1
do   if conpath[cont] = '\' then     begin       Result :=
Copy(conpath, cont+1, Length(conpath));       Break;   
 end;end; procedure TExplorerForm.SBUpPathClick(Sender: TObject);var 
contador : integer;beginfor contador := length(FActiveDir) downto 1
do   begin   if FActiveDir[contador] = '\' then      begin       
FActiveDir := copy(FActiveDir,1,contador-1);       
LoadDirectory(FActiveDir);        Break;      end; 
 end;end; finalization   explorer.Free;  explorer := Nil; end.

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lucamar · 2021-01-26 14:48

FileExist() should return True for an existing full-qualified file
name ... except when the name is that of a directory; in that case it
will return False and you'll have to use DirectoryExist().

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torbente · 2021-01-26 16:14

Fixed!

@Howadpc: how is the best way to handle the explorer form wjen the
user finish with it? close? Destroy? visible :=false?

Quote from: lucamar on January 26, 2021, 03:48:32 pmFileExist() should
return True for an existing full-qualified file name ... except when
the name is that of a directory; in that case it will return False and
you'll have to use DirectoryExist().

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howardpc · 2021-01-26 16:27

All classes must be freed after use to avoid memory leaks.
There are various ways to do this. The code I gave you relied on a
unit finalization routine.

Alternatively you could make the Application the form's Owner (rather
than having a Nil Owner), or you could explicitly Create and Free a
form instance in your main form's code somewhere if you only need the
form for a limited period in the lifetime of your app. It's up to you.

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Martin_fr · 2021-01-26 17:33

Quote from: torbente on January 26, 2021, 02:26:08 pmThanks a lot. I
did not have idea i need declare a new class for the form.

Note, you do not need to inherit TForm.

The only thing that you need is a class. And you need to instantiate
it.
Code: Pascal  [Select][+][-]window.onload = function(){var x1 =
document.getElementById("main_content_section"); if (x1) { var x =
document.getElementsByClassName("geshi");for (var i = 0; i type 
TMyClass = class    procedure FSBOkFileOnClick(Sender: TObject); 
end; ...   FSBOkFile := TSpeedButton.Create(Self);  with FSBOkFile do 
  begin...      OnClick := @FSBOkFileOnClick; 
Thus the event is a method.

Of course it makes sense to make your global vars, fields in that
class. Just to keep some order (though order is a subjective concept).
If you don't inherit TForm, then you could have a field "FMyForm:
TForm".