Delphi REST not updating VCL db components when created runtime - rest

I have a REST client which sends a request and updates some VCL db components with the response using an adapter, that works fine when the REST VCL components are put on a TDatamodule, however if I try to create the same REST components runtime, the VCL db components are not showing the data. I can see that the data are in fact returned (I can read them in the FDMemtable and store the data as a file) so the data is there, but the GUI components doesnt display data. The DBGrid does however show the vertical scroll bare after the update.
I'm using Delphi XE10.2.
I got stuck with this, I got to be missing something.
function TRESTClientModule.UpdateHistory: Boolean;
var
ARESTClient : TRESTClient;
ARESTRequest: TRESTRequest;
ARESTResponse: TRESTResponse;
ARESTResponseDataSetAdapter: TRESTResponseDataSetAdapter;
i : Integer;
s : string;
begin
Result := False;
try
ARESTClient := TRESTClient.Create('http://localhost:8080');
ARESTRequest := TRESTRequest.Create(nil);
ARESTResponse := TRESTResponse.Create(nil);
ARESTResponseDataSetAdapter := TRESTResponseDataSetAdapter.Create(nil);
try
// bind to RESTClient
ARESTRequest.Client := ARESTClient;
//- Prepare to get data from 'alarms' end-point.
ARESTRequest.Resource := 'alarms';
ARESTRequest.Method := TRESTRequestMethod.rmGET;
ARESTRequest.Response := ARESTResponse;
// Link Response to dataset (FDMemtable + TDataSource)
ARESTResponseDataSetAdapter.Dataset := AlarmHistory;
ARESTResponseDataSetAdapter.ResponseJSON := ARESTResponse;
ARESTResponseDataSetAdapter.RootElement := 'alarms';
//- Add the parameter to the request.
ARESTREquest.Params.Clear;
with ARESTRequest.Params.AddItem do
begin
name := 'IncludeOOS';
value := '0';
end;
ARESTRequest.Execute;
s := ARESTResponse.Content; // returned content is present
i := AlarmHistory.RecordCount; // the expected Recordcount is present
Result := True;
finally
ARESTResponse.Free;
ARESTResponseDataSetAdapter.Free;
ARESTRequest.Free;
end;
except on E: Exception do
end;
end;

Related

Delphi Unique Dynamic Form Creation

I am using multiple forms on my project. (Client Server Application) I used chat but i have some problems.
1- I have a user list on my listview. And i am open new chat form here.
procedure CreateNewChat(User: String);
var
ChatForm: TChatForm;
begin
ChatForm:= TChatForm.Create(nil);
if assigned (ChatForm) then
ChatForm.User:= User;
Chat.Socket:= MySocket; // TClientSocket new Instance
ChatForm.Show;
end;
///Chatform
procedure ParseData(Cmd:string);
begin
if Cmd <> '' then
begin
/// parsing...
end;
New connections are adding to listview like that
var
Item: TListItem;
NewTempForm: TTempForm;
begin
NewTempForm := tempForm.Create;
Item := Listview.Items.Add;
if User = '' then
Exit;
Item.Caption := User;
Item.SubItems.Add('OK');
Item.GroupId := GroupId;
Item.SubItems.Objects[0] := NewTempForm;
end;
My problems are started on here.
1- How can i detect form according to user? So, if two or higher form is open then how can i show received message on them? Because i was create them dynamically. I need a object for detect.
I tryed like that
var
tempForm: TTempForm; // this is an empty object class
sTempStr: String;
begin
if ListView.Selected <> nil then
begin
tempForm := TTempForm(ListView.Selected.SubItems.Objects[0]); // this is for unique form creation
if tempForm.frmTasks = nil then // if there is not, create!
begin
tempForm.frmTasks := TfrmTasks.Create(nil);
end;
But my received message is appear on all forms. Actually should appear just one form. (Which user sent it)
Thanks.

How to prevent using anything except application in Delphi XE

I'm developing a VCL Form Application
When the application started
I need to prevent the user of the computer to do anything
He can't close the application by ALT+F4 or CTRL+ALT+DEL
He can't change to another window by ALT+Tab
He can't Go to the desktop by clicking Windows + D
This will used in Cyber Cafe and it is a Server/Client application
so before the Admin in the Server giving access to the Client, He can't do anything in the computer .. just a full screen for my form
Because it is the login system of Windows that traps the CTRL-ALT-DEL combination (and so it is not accessible to user applications), you will need to change the system's keyboard scancode map to ignore at least one of those keys.
First you have to ensure Autologon on your computer, else you can login. This could also be done in the registry.
Then the tricky part editing the scancode map. In MSDN you'll find an article about how to do: https://msdn.microsoft.com/en-us/library/windows/hardware/jj128267%28v=vs.85%29.aspx?f=255&MSPPError=-2147217396
I've found this reg file that is suppose to disable CTRL + ALT + DELETE but I havent tested it
Windows Registry Editor Version 5.00
[HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Keyboard Layout]
"Scancode Map"=hex:00,00,00,00,00,00,00,00,03,00,00,00,00,00,38,00,00,00,38,e0,\
00,00,00,00
Be aware that this is extremely hirisk. Both using the REG file and changing the scancode map. I suggest you test your stuff in a virtual Machine.
You also need to prevent the user from shuttingdown the computer. Which is also done in registry:
User Key: [HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Policies\
Explorer]
System Key: [HKEY_LOCAL_MACHINE\Software\Microsoft\Windows\CurrentVersion\Policies\
Explorer]
Value Name: NoClose
Data Type: REG_DWORD (DWORD Value)
Value Data: (0 = shutdown enabled, 1 = shutdown disabled)
So inorder for shuttingdown the computer your probram must make a call to ShutdownwindowsEx
function ExitWindows(iFlags: Integer): Boolean;
var
osVerInfo: TOSVersionInfo;
function SetPrivilege(sPrivilegeName: string; bEnabled: Boolean): Boolean;
var
TPPrev, TP: TTokenPrivileges;
Token: THandle;
dwRetLen: DWord;
begin
Result := False;
OpenProcessToken(GetCurrentProcess, TOKEN_ADJUST_PRIVILEGES or TOKEN_QUERY, Token);
TP.PrivilegeCount := 1;
if (LookupPrivilegeValue(nil, PChar(sPrivilegeName), TP.Privileges[0].LUID)) then
begin
if (bEnabled) then
TP.Privileges[0].Attributes := SE_PRIVILEGE_ENABLED
else
TP.Privileges[0].Attributes := 0;
dwRetLen := 0;
Result := AdjustTokenPrivileges(Token, False, TP, sizeof(TPPrev), TPPrev, dwRetLen);
end;
CloseHandle(Token);
end;
begin
Result := True;
osVerInfo.dwOSVersionInfoSize := sizeof(TOSVersionInfo);
if GetVersionEx(osVerInfo) then
case osVerInfo.dwPlatformId of
VER_PLATFORM_WIN32_WINDOWS:
if not ExitWindowsEx(iFlags, 0) then
Result := False; // handle errors...
VER_PLATFORM_WIN32_NT:
if SetPrivilege('SeShutdownPrivilege', True) then
begin
if not ExitWindowsEx(iFlags, 0) then
Result := False; // handle errors...
SetPrivilege('SeShutdownPrivilege', False)
end
else
Result := False; // handle errors...
else
Result := False;
end;
end;

Send/Receive text with buffer using sockets in Delphi

So I have searched for a way to make this work but found no working solution. I am trying to send text that has been inserted in to a memo from the Client to the Server using sockets. Unfortunately I cannot get the coding working. It might be something stupid I'm doing wrong; but I don't know where the mistake is. I created a stable connection between the server and client, and I am able to send text using Server.Socket.Connections[Form1.ListView1.Selected.Index].SendText('Texthere'); but I just cant get it to send and receive text or anything using buffers.
Code on Client:
procedure TIBAT.Sends1Click(Sender: TObject); //Button to start the sending of the text on the memo component
var
ms: TMemoryStream;
size: Integer;
begin
if (Form1.ListView1.Selected <> nil) then //if a server is selected
begin
Form1.Server.Socket.Connections[Form1.ListView1.Selected.Index].SendText('IBAT');
ms:= TMemoryStream.Create;
try
IBAT.Memo1.Lines.SaveToStream(ms);
ms.Position:= 0;
Size:= MS.Size;
Form1.Server.Socket.Connections[Form1.ListView1.Selected.Index].SendBuf(Size,SizeOf(Size));
Form1.Server.Socket.Connections[Form1.ListView1.Selected.Index].SendStream(ms);
except
ms.Free;
ShowMessage('FAILED');
end;
end;
end;
Code on the Server:
private
Stream: TMemoryStream;
FSize: Integer;
writing: Boolean;
...
procedure TSock.ClientRead(Sender: TObject; Socket: TCustomWinSocket);
var
Command :String;
BytesReceived: Longint;
CopyBuffer: Pointer; //buffer for copying
ChunkSize: Integer;
TempSize: Integer;
const
MaxChunkSize: Longint = 8192;
begin
Command := Socket.ReceiveText;
if split(Command, '|', 0) = 'IBAT' then
begin
If FSize=0 then
begin
//ShowMessage(IntToStr(Socket.ReceiveLength)); added messageboxes everywhere to figure out where the problem is
If Socket.ReceiveLength>SizeOf(TempSize) then
begin
Socket.ReceiveBuf(TempSize,SizeOf(TempSize));
Stream:= TMemoryStream.Create;
Stream.SetSize(TempSize);
//ShowMessage(IntToStr(TempSize));
FSize:= TempSize;
writing:= True;
End;
End;
If (FSize>0) and (writing) then
begin
GetMem(CopyBuffer, MaxChunkSize); //allocate the buffer
While Socket.ReceiveLength>0 do
Begin
ChunkSize:= Socket.ReceiveLength;
If ChunkSize > MaxChunkSize then ChunkSize:= MaxChunkSize;
BytesReceived:= Socket.ReceiveBuf(CopyBuffer^,ChunkSize);
Stream.Write(CopyBuffer^, BytesReceived); //write chunk
Dec(FSize,BytesReceived);
End;
FreeMem(CopyBuffer, MaxChunkSize); //free allocated buffer
If FSize = 0 then
begin
Stream.SaveToFile(TempDir+IntToStr(GetTickCount)+'.cmd');
Socket.SendText('File received!');
Stream.SetSize(0);
FSize:= 0;
End;
FreeMem(CopyBuffer, MaxChunkSize);
Writing:= False;
End;
end;
I know using Indy is more effective and better than sockets, but I've already started coding using it and switching over to Indy is a big pain.
If anyone can help me get this working I would really appreciate it.
I've just make a very-very simple example of TCP client and server on Indy. It is very simple, even no exceptions handling there.
Take a look at a repository at github and feel free to ask any questions.
Anyway, using of native socket components is not a good idea. Try to study Indy, then Synapse or mORMot may be. Indy will be a good start.
UPD I'll try to get some code here in answer:
Start a TCP server listening on specified port:
var
IdTcpServer1: TIdTcpServer
[...]
IdTcpServer1.DefaultPort := SERVER_PORT;
IdTcpServer1.Active := True;
Server will start listening on 0.0.0.0:1234.
Connect a TCP client to TCP server:
var
IdTcpClient1: TIdTcpClient;
[...]
IdTcpClient1.Host := SERVER_HOST; // IP or DNS name
IdTcpClient1.Port := SERVER_PORT;
IdTcpClient1.Connect;
Send a text line to socket (after it's connected):
IdTcpClient1.IOHandler.Writeln('Hello world!');
Server must implement OnExecute event handler:
// manual init in code or you can assign it in design-time in IDE
IdTcpServer1.OnExecute := IdTcpServer1ExecuteHandler;
[...]
// very simple example
procedure IdTcpServer1ExecuteHandler(AContext: TIdContext);
var
s: string;
begin
s := AContext.Connection.IOHandler.ReadLn();
if s <> EmptyStr then
begin
// do something with received string s
end;
end;

Using Word OLE in Lazarus FreePascal

Im trying to get FreePascal to open up a word document, append some text and data to it and then close it. I've managed to get connected and can write a single line to the document but anything over that is defeating me. Currently I am attempting methods details in this Visual Basic reference, which is pretty similar to how I would expect FreePascal to handle things.
Basically I think I have misunderstood how the relationship between Lazarus and the Word OLE actually works, can anyone offer me any examples on how to construct a simple document that I can build on?
The following code, opens the document but then completely replaces its contents
program officAuto;
{$IFDEF FPC}
{$MODE Delphi}
{$ELSE}
{$APPTYPE CONSOLE}
{$ENDIF}
uses
SysUtils, Variants, ComObj;
const
ServerName = 'Word.Application';
var
Server, Doc : Variant;
oPara : Variant;
w:widestring;
begin
if Assigned(InitProc) then
TProcedure(InitProc);
try
Server := CreateOleObject(ServerName);
except
WriteLn('Unable to start Word.');
Exit;
end;
w:= UTF8Decode('c:\mydoc.docx');
Server.Visible := True; {Make Word visible}
Doc := Server.Documents.Open(w);
Doc.Range.Text := 'This is a Heading';
Doc.Range.Font.Bold := True;
Doc.Format.SpaceAfter := 24;
end.
Whereas this, based on the code above, in attempting to print a string at a bookmark, opens the document, retains the contents, moves to the bookmark and then does nothing.
w:= UTF8Decode('c:\mydoc.docx');
Server.Visible := True;
Doc := Server.Documents.Open(w);
oPara := Doc.Content.Paragraphs.Add(Doc.Bookmarks.Item('\Bookmark1').Range);
oPara := Doc.Range.Text('Where will this appear if at all!');
Ah I worked it out. The following code works as expected:
program officAuto;
{$IFDEF FPC}
{$MODE Delphi}
{$ELSE}
{$APPTYPE CONSOLE}
{$ENDIF}
uses
SysUtils, Variants, ComObj;
var
Server, Connect : Variant;
oWord, oPara1, oPara2 : Variant;
w:widestring;
begin
if Assigned(InitProc) then
TProcedure(InitProc);
try
Server := CreateOleObject('Word.Application');
except
WriteLn('Unable to start Word.');
Exit;
end;
// oWord := Server.Documents.Add;
w:= UTF8Decode('c:\mydoc.docx');
Server.Visible := True;
Server.Documents.Open(w);
oPara1 := Server.ActiveDocument.Content.Paragraphs.Add;
oPara1.Range.Text := 'This is a Heading';
oPara1.Range.Font.Bold := True;
oPara1.Format.SpaceAfter := 24;
oPara1.Range.InsertParagraphAfter();
oPara2 := Server.ActiveDocument.Content.Paragraphs.Add;
oPara2.Range.Text := 'Where will this appear if at all!';
oPara2.Range.Font.Bold := False;
oPara2.Format.SpaceAfter := 24;
oPara2.Range.InsertParagraphAfter();
end.

InnoSetup Dynamic ComboBox, check which item is selected and execute program

In InnoSetup I want to disply a ComboBox on the Finished Page which shows the Components that were installed.
You can choose "None" or any of the installed Components and start the associated program when clicking on finish.
This is my code so far:
procedure CurPageChanged(CurPageID: Integer);
var
NewComboBox1: TNewComboBox;
begin
if (CurPageID = wpFinished) then begin
NewComboBox1 := TNewComboBox.Create(WizardForm);
with NewComboBox1 do begin
Parent := WizardForm.FinishedPage;
Left := ScaleX(256);
Top := ScaleY(208);
Width := ScaleX(145);
Height := ScaleY(21);
ItemIndex := 0;
Style := csDropDownList;
Items.Add('None');
if IsComponentSelected('1') then
Items.Add('Component 1');
if IsComponentSelected('2') then
Items.Add('Component 2');
if IsComponentSelected('3') then
Items.Add('Component 3');
end;
end;
end;
First I want to set "None" as automatically selected. when the page is shown. I have looked up many Pascal forums but none of the solutions worked, like NewComboBox1.ItemSelected=0 (or similar, don't remember correctly...). So how do I achieve this?
Then I don't know how to make a program start when clicking on Finish. I thought
function NextButtonClick
might help but then no Next button worked in the setup.
Maybe there is also a problem because the list is created depending on which Components were selected, so item 1 is not Component 1, if Component 1 was not selected but Component 2 for instance.
I thought one might solve this by making the items invisible instead of not creating them at all.
I looked in the Support Classes Reference in the IS help file but didn't find anything that would help me.
I am looking forward to your answers!
There's no simple way to do this due to a lack of missing access to the file name and destination directory which the component is binded to. Even TSetupComponentEntry internal record doesn't contain this information, but even if would, you won't be able to access it. So, the following script uses its own separate array which contains the component/file linkage needed for this task:
[Setup]
AppName=My Program
AppVersion=1.5
DefaultDirName={pf}\My Program
[Components]
Name: "program_32"; Description: "Program 32-bit"
Name: "program_x64"; Description: "Program 64-bit"
Name: "program_ia64"; Description: "Program IA 64-bit"
[Files]
Source: "MyProg.exe"; DestDir: "{app}"; Components: program_32
Source: "MyProg-x64.exe"; DestDir: "{app}"; Components: program_x64
Source: "MyProg-IA64.exe"; DestDir: "{app}"; Components: program_ia64
[Code]
type
TFileData = record
Component: string;
Description: string;
FileName: string;
Parameters: string;
end;
var
ComponentCombo: TNewComboBox;
ComponentArray: array of TFileData;
SelectionArray: array of TFileData;
procedure InitializeWizard;
begin
// this is a weakness of this solution - you need to fill the array
// of components that can be added to the final combo box when they
// are selected on component selection page. This is needed because
// you can't get neither file name nor destination directory of the
// file for the component from script. As first, set how many items
// you want to add to your component array storage
SetArrayLength(ComponentArray, 2);
// the Component member must match to the "Name" parameter from the
// [Components] section item since it's used in IsComponentSelected
// function call
ComponentArray[0].Component := 'program_32';
// the Description member is the text displayed in the combo item
ComponentArray[0].Description := 'Program 32-bit';
// the FileName member is the name of the file including path. This
// member may contain InnoSetup constants
ComponentArray[0].FileName := '{app}/MyProg.exe';
// the Parameters member contains execution parameters
ComponentArray[0].Parameters := '-a';
// this is the second item that can be added to the combo box, note
// that the program_ia64 component is not added to this array, what
// means, that it cannot be added to the "run" combo box. It's such
// kind of a filter for components like help files etc.
ComponentArray[1].Component := 'program_x64';
ComponentArray[1].Description := 'Program 64-bit';
ComponentArray[1].FileName := '{app}/MyProg-x64.exe';
ComponentArray[1].Parameters := '-b';
end;
procedure CurPageChanged(CurPageID: Integer);
var
I: Integer;
begin
if (CurPageID = wpFinished) then
begin
ComponentCombo := TNewComboBox.Create(WizardForm);
ComponentCombo.Parent := WizardForm.FinishedPage;
ComponentCombo.Left := ScaleX(256);
ComponentCombo.Top := ScaleY(208);
ComponentCombo.Width := ScaleX(145);
ComponentCombo.Height := ScaleY(21);
ComponentCombo.Style := csDropDownList;
ComponentCombo.Items.Add('None');
for I := 0 to GetArrayLength(ComponentArray) - 1 do
if IsComponentSelected(ComponentArray[I].Component) then
begin
ComponentCombo.Items.Add(ComponentArray[I].Description);
SetArrayLength(SelectionArray, GetArrayLength(SelectionArray) + 1);
SelectionArray[High(SelectionArray)] := ComponentArray[I];
end;
ComponentCombo.ItemIndex := 0;
end;
end;
function NextButtonClick(CurPageID: Integer): Boolean;
var
FileData: TFileData;
ResultCode: Integer;
begin
Result := True;
if (CurPageID = wpFinished) and (ComponentCombo.ItemIndex > 0) then
begin
FileData := SelectionArray[ComponentCombo.ItemIndex - 1];
Exec(ExpandConstant(FileData.FileName), FileData.Parameters, '', SW_SHOW,
ewNoWait, ResultCode);
end;
end;