[SOLVED] Browsing For Folder in Linux
lazarus / 32-Linux

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Sandstone · 2020-11-02 01:44

I have some existing Pascal Windows code I'm trying to port for Linux
and am getting multiple errors:

function TMainForm.BrowseForFolder(var Path: string): Boolean;
var
  BI: TBrowseInfo;
  p: PItemIDList;
  s, t: string;
const
  BIF_NONEWFOLDERBUTTON = $00000200;
begin
  Result := False;
  ZeroMemory(@BI,SizeOf(BI));
  SetLength(t,MAX_PATH);
  with BI do begin
    hwndOwner := Handle;
    pidlRoot := nil;
    pszDisplayName := PChar(t);
    lpszTitle := PChar(S_SelectPathToExplore);
    ulFlags := BIF_NEWDIALOGSTYLE or BIF_NONEWFOLDERBUTTON or
BIF_RETURNONLYFSDIRS or BIF_VALIDATE;
  end;
  p := SHBrowseForFolder(BI);
  if Assigned(p) then
    try
      SetLength(s, MAX_PATH);
      if SHGetPathFromIDList(p, PChar(s)) then begin
        Result := True;
        Path := PChar(s);
      end;
    finally
      CoTaskMemFree(p);
    end;
end;

MainFormUnit.pas(2152,7) Error: Identifier not found "TBrowseInfo"
MainFormUnit.pas(2153,6) Error: Identifier not found "PItemIDList"
MainFormUnit.pas(2159,3) Error: Identifier not found "ZeroMemory"
MainFormUnit.pas(2162,5) Error: Identifier not found "hwndOwner"
MainFormUnit.pas(2163,5) Error: Identifier not found "pidlRoot"
MainFormUnit.pas(2164,5) Error: Identifier not found "pszDisplayName"
MainFormUnit.pas(2165,5) Error: Identifier not found "lpszTitle"
MainFormUnit.pas(2166,5) Error: Identifier not found "ulFlags"
MainFormUnit.pas(2166,16) Error: Identifier not found
"BIF_NEWDIALOGSTYLE"
MainFormUnit.pas(2166,63) Error: Identifier not found
"BIF_RETURNONLYFSDIRS"
MainFormUnit.pas(2166,87) Error: Identifier not found "BIF_VALIDATE"
MainFormUnit.pas(2168,8) Error: Identifier not found
"SHBrowseForFolder"

Am I missing a package or unit that handles this?

Units I have are:
uses
  LCLIntf, LCLType, LMessages, Messages, SysUtils, Variants, Classes,
Graphics, Controls, Forms,
  Dialogs, IniFiles, StdCtrls, Grids, ComCtrls, Types,
  ExtCtrls, Buttons, Organ, ToolWin, Menus, VirtualTrees, ImgList,
  FakeActiveX,  CheckLst, ObjectMatrixFrameUnit,
  Themes,
  {project units}
  WoodFormUnit, ScanFormUnit, ExportFormUnit,
  WarningFormUnit, ConfigurationFormUnit, SplashFormUnit;

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Handoko · 2020-11-02 03:19

Free Pascal Compiler is a cross platform compiler. But that does not
mean you can just compile all the source codes that work on a platform
to other platforms. The codes must be written to support cross
compiling, which usually mean not using any platform or OS specific
function.

In the list of units you provided, I think these are not able to
compile to Linux:
Organ, ToolWin, FakeActiveX, ObjectMatrixFramUnit.

The name ToolWin suggests it works on Windows only. And as far as I
know Linux does not support ActiveX technology.

If you really want to make the existing BrowseForFolder code to be
able to compile to Linux, you have some possible solutions:
- If you have the source codes of all the units, study them and
manually convert them to Linux-friendly units
- Or you can share all of them on the forum and ask someone to help
you if the licenses allow you to do that
- You can consider to create a bounty for the task

But I think the most easiest thing to do is abandon the code and write
a new cross-compile-friendly code. Browse for folder does not sound
difficult. Not exactly what you want but Lazarus itself has components
that you can use or study: TOpenDialog, TFileListBox, TShellListView.

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lucamar · 2020-11-02 05:34

All that code is entirely Windows-specific so you won't be able to
make it work on Linux. Also, note that, generally speaking, Linux
neither has or need a "Browse for folder" dialog, since most, if not
all, of its funcions are present in the standard "Open file" dialog or
its Lazarus specialization TSelectDirectory.

If you really want one looking more or less like the Windows one you
might mimic it by building your own; the easiest way will probably be
using a TShellListView, as Handoko said.

But if I were you I would just replace all that for a
SelectDirectoryDialog for all platforms.

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Sandstone · 2020-11-02 17:14

Quote from: Handoko on November 02, 2020, 04:19:56 amBut I think the
most easiest thing to do is abandon the code and write a new cross-
compile-friendly code.
I expected that this would be where I would end up with this.   No
worries, I still have the Windows version that will run in Wine 5.0.2

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balazsszekely · 2020-11-02 19:55

@Sandstone

There is a crossplatform TSelectDirectoryDialog component(Dialog
palette) shipped with Lazarus. If you check Options->ofOldStyleDialog
it looks exactly like the one created with your BrowseForFolder
function.

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Bart · 2020-11-02 20:21

If you insist on using the old function (so you don't have to change
the code that is calling it), try 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 function
TMainForm.BrowseForFolder(var Path: string): Boolean;var  Dlg:
TSelectDirectoryDialog;begin  Dlg :=
TSelectDirectoryDialog.Create(nil);  try    Dlg.InitialDir := Path;  
Result := Dlg.Execute;    if Result then      Path := Dlg.FileName; 
finally   Dlg.Free;  end;end;
Bart