how to show the availble files in Android memory with Firemonkey

Question

In Delphi for Windows one has the TOpenDialog and the commands such as FindFirst. In Firemonky/Android there is no TOpenDialog, but according to many forumsFindFirst` should exist. However there are more who have problems with it, but no solution:

In Windows the following functions properly:

var iResult,n:integer;
Filenaam,s:string;
sr: TSearchRec;

begin

with form1 do
begin
    L_toonactie.Text:='start file list';
    M_filelist.lines.Clear;
    Filenaam:=
          System.IOUtils.tpath.GetDocumentsPath+'\assets\internal\'+'*.*';          
    iResult:=FindFirst(Filenaam,faAnyFile,sr); 
    str(iresult,s);L_toonactie.Text:='started '+s;
    n:=0;
    while (iResult=0) do
    begin
        inc(n);
        L_toonactie.Text:='busy file list';
        s:=s+sr.Name+sLineBreak;
        M_filelist.lines.add(sr.name);
        iResult:=FindNext(sr);
    end;
  FindClose(sr);
 // str(n,s);if n=0 then L_toonactie.Text:='nothing found' 
else L_toonactie.Text:='ready file list ('+s+'found)'

end;}

iResult always has -1

Another solution found was:

procedure toon_files2(pathSTRING:string);  
var
   {$IFDEF FPC}
   patharray : NSArray;
   filename,path,ext,subdir:NSString ;
   fileManager: NSFileManager ;
   direnum:NSEnumerator;//NSDirectoryEnumerator ;//NSDirectoryEnumerator;
   //direnum:NSDirectoryEnumerator ;//NSDirectoryEnumerator;
   i,n:integer;
   error:NSError;
   {$ENDIF}
   k:integer;
begin
form1.L_toonactie.Text:='start file list';

{$IFDEF FPC}
path:= NSSTR(PChar(pathSTRING)); // =NSHomeDirectory();//
fileManager:= NSFileManager.defaultManager;
patharray:= fileManager.contentsOfDirectoryAtPath_error(path,@error);
n:=0;
k:=0;
direnum:= patharray.objectEnumerator ;
repeat
    inc(k);
    filename:=direnum.nextObject;
    if string(fileName.UTF8STRING)<>'' then
    begin
        ext:= filename.pathExtension;
        if UpperCase(string(ext.UTF8STRING))='KPF' then
        begin
            form1.L_toonactie.Text:='found a file';
            SetLength(pngLIST,n+1);
            pngLIST[n]:=string(Path.UTF8STRING)+string(filename.UTF8STRING);
            form1.memo1.Lines.Add(pngLIST[n]) ;
            inc(n);
        end;
    end;
until string(fileName.UTF8STRING)='';
{$ENDIF}

if k=0 then form1.L_toonactie.Text:='nothing found' 
else form1.L_toonactie.Text:='ready file list';
end;

But does not work either.

Answer 1

The functionality available in IOUtils is all you need. This code (tested on my Nexus 7) populates a TMemo with the files in your folder (if there are any):

uses
  IOUtils;

procedure THeaderFooterForm.SpeedButton1Click(Sender: TObject);
var
  DirList: TStringDynArray;
  DirPath: string;
  s: string;
begin
  DirPath := TPath.Combine(TPath.GetDocumentsPath, 'assets');
  DirPath := TPath.Combine(DirPath, 'internal');

  // Display where we're looking for the files
  Memo1.Lines.Add('Searching ' + DirPath);

  if TDirectory.Exists(DirPath, True) then
  begin
    // Get all files. Non-Windows systems don't typically care about
    // extensions, so we just use a single '*' as a mask.
    DirList := TDirectory.GetFiles(DirPath, '*');

    // If none found, show that in memo
    if Length(DirList) = 0 then
      Memo1.Lines.Add('No files found in ' + DirPath)
    else // Files found. List them.
    begin 
      for s in DirList do
        Memo1.Lines.Add(s);
    end;
  end
  else
    Memo1.Lines.Add('Directory ' + DirPath + ' does not exist.');
end;