Step by Step Creating a Basic WebSockets Application

In order to make yourself familiar with WebSockets in uniGUI the best way is to test this feature in a simple application.

Create a new uniGUI standalone application

Create a new uniGUI standalone application in your Delphi environment.

Enable WebSocketConnection on the MainModule

Open the MainModule and enable the WebSocketConnection property. Enabling this property will force sessions to establish a WebSocket connection to the server. This connection will be used to receive messages from the server.

Add a button to MainForm

Open MainForm and place a button on it.

Broadcast a message from the server

Add an event handler to the button and call BroadcastMessage as shown below.

MainForm - Button Click

procedure TMainForm.UniButton1Click(Sender: TObject);
begin
  BroadcastMessage('msg', ['text', 'This is the message!']);
end;

Handle broadcasted messages on the client/session

Add an event handler to the MainForm named OnBroadcastMessage to receive and handle the broadcasted message:

MainForm - OnBroadcastMessage

procedure TMainForm.UniFormBroadcastMessage(const Sender: TComponent;
  const Msg: string; const Params: TUniStrings);
begin
  if Msg = 'msg' then
  begin
    ShowMessage(Params['text'].AsString);
  end;
end;

Run and test the application

Run the application. In the web browser open a new tab and navigate to the application URL (for example, http://localhost:8077 depending on your port configuration). In the web application press the button — a message window should display the text parameter.