CEF4Delphi/demos/Lazarus_Windows/FullScreenBrowser/uMainForm.pas

unit uMainForm;

{$MODE Delphi}

interface

uses
  {$IFDEF DELPHI16_UP}
  Winapi.Windows, Winapi.Messages, System.SysUtils, System.Variants, System.Classes, Vcl.Graphics,
  Vcl.Controls, Vcl.Forms, Vcl.Dialogs,
  System.UITypes,
  {$ELSE}
  LCLIntf, LCLType, LMessages, Messages, SysUtils, Variants, Classes, Graphics,
  Controls, Forms, Dialogs, ExtCtrls,
  {$ENDIF}
  uCEFChromium, uCEFWindowParent, uCEFInterfaces, uCEFTypes, uCEFConstants,
  uCEFWinControl;

type

  { TMainForm }

  TMainForm = class(TForm)
    CEFWindowParent1: TCEFWindowParent;
    Chromium1: TChromium;
    Timer1: TTimer;
    procedure CEFSentinel1Close(Sender: TObject);
    procedure Chromium1PreKeyEvent(Sender: TObject;
      const browser: ICefBrowser; const event: PCefKeyEvent; osEvent: TCefEventHandle;
      out isKeyboardShortcut, Result: Boolean);
    procedure Chromium1KeyEvent(Sender: TObject;
      const browser: ICefBrowser; const event: PCefKeyEvent; osEvent: TCefEventHandle;
      out Result: Boolean);
    procedure FormShow(Sender: TObject);
    procedure Chromium1AfterCreated(Sender: TObject;
      const browser: ICefBrowser);
    procedure Timer1Timer(Sender: TObject);
    procedure Chromium1BeforePopup(Sender: TObject;
      const browser: ICefBrowser; const frame: ICefFrame; const targetUrl,
      targetFrameName: ustring;
      targetDisposition: TCefWindowOpenDisposition; userGesture: Boolean;
      const popupFeatures: TCefPopupFeatures; var windowInfo: TCefWindowInfo;
      var client: ICefClient; var settings: TCefBrowserSettings;
      var extra_info: ICefDictionaryValue;
      var noJavascriptAccess: Boolean; var Result: Boolean);
    procedure FormCreate(Sender: TObject);
    procedure FormCloseQuery(Sender: TObject; var CanClose: Boolean);
    procedure Chromium1BeforeClose(Sender: TObject;
      const browser: ICefBrowser);
    procedure Chromium1Close(Sender: TObject; const browser: ICefBrowser;
      var aAction : TCefCloseBrowserAction);
  private
    { Private declarations }
  protected
    // Variables to control when can we destroy the form safely
    FCanClose : boolean;  // Set to True in TChromium.OnBeforeClose
    FClosing  : boolean;  // Set to True in the CloseQuery event.

    procedure WMMove(var aMessage : TWMMove); message WM_MOVE;
    procedure WMMoving(var aMessage : TMessage); message WM_MOVING;
    procedure WMEnterMenuLoop(var aMessage: TMessage); message WM_ENTERMENULOOP;
    procedure WMExitMenuLoop(var aMessage: TMessage); message WM_EXITMENULOOP;
    procedure BrowserCreatedMsg(var aMessage : TMessage); message CEF_AFTERCREATED;
    procedure BrowserDestroyMsg(var aMessage : TMessage); message CEF_DESTROY;

    procedure HandleKeyUp(const aMsg : TMsg; var aHandled : boolean);
    procedure HandleKeyDown(const aMsg : TMsg; var aHandled : boolean);
  public
    { Public declarations }
  end;

var
  MainForm: TMainForm;

procedure CreateGlobalCEFApp;

implementation

{$R *.lfm}

uses
  uCEFApplication;   

// Destruction steps
// =================
// 1. FormCloseQuery sets CanClose to FALSE calls TChromium.CloseBrowser which triggers the TChromium.OnClose event.
// 2. TChromium.OnClose sends a CEFBROWSER_DESTROY message to destroy CEFWindowParent1 in the main thread, which triggers the TChromium.OnBeforeClose event.
// 3. TChromium.OnBeforeClose calls TCEFSentinel.Start, which will trigger TCEFSentinel.OnClose when the renderer processes are closed.
// 4. TCEFSentinel.OnClose sets FCanClose := True and sends WM_CLOSE to the form.

procedure CreateGlobalCEFApp;
begin
  GlobalCEFApp                     := TCefApplication.Create;  
  //GlobalCEFApp.LogFile          := 'cef.log';
  //GlobalCEFApp.LogSeverity      := LOGSEVERITY_VERBOSE;
end;

procedure TMainForm.HandleKeyUp(const aMsg : TMsg; var aHandled : boolean);
var
  TempMessage : TMessage;
  TempKeyMsg  : TWMKey;
begin
  TempMessage.Msg     := aMsg.message;
  TempMessage.wParam  := aMsg.wParam;
  TempMessage.lParam  := aMsg.lParam;
  TempKeyMsg          := TWMKey(TempMessage);

  if (TempKeyMsg.CharCode = VK_ESCAPE) then
    begin
      aHandled := True;

      PostMessage(Handle, WM_CLOSE, 0, 0);
    end;
end;

procedure TMainForm.Timer1Timer(Sender: TObject);
begin
  Timer1.Enabled := False;
  if not(Chromium1.CreateBrowser(CEFWindowParent1, '')) and not(Chromium1.Initialized) then
    Timer1.Enabled := True;
end;

procedure TMainForm.HandleKeyDown(const aMsg : TMsg; var aHandled : boolean);
var
  TempMessage : TMessage;
  TempKeyMsg  : TWMKey;
begin
  TempMessage.Msg     := aMsg.message;
  TempMessage.wParam  := aMsg.wParam;
  TempMessage.lParam  := aMsg.lParam;
  TempKeyMsg          := TWMKey(TempMessage);

  if (TempKeyMsg.CharCode = VK_ESCAPE) then aHandled := True;
end;

procedure TMainForm.Chromium1AfterCreated(Sender: TObject; const browser: ICefBrowser);
begin
  PostMessage(Handle, CEF_AFTERCREATED, 0, 0);
end;

procedure TMainForm.Chromium1BeforeClose(Sender: TObject; const browser: ICefBrowser);
begin
  FCanClose := True;
  PostMessage(Handle, WM_CLOSE, 0, 0);
end;

procedure TMainForm.Chromium1BeforePopup(Sender: TObject;
  const browser: ICefBrowser; const frame: ICefFrame; const targetUrl,
  targetFrameName: ustring; targetDisposition: TCefWindowOpenDisposition;
  userGesture: Boolean; const popupFeatures: TCefPopupFeatures;
  var windowInfo: TCefWindowInfo; var client: ICefClient;
  var settings: TCefBrowserSettings;
  var extra_info: ICefDictionaryValue;
  var noJavascriptAccess: Boolean;
  var Result: Boolean);
begin
  // For simplicity, this demo blocks all popup windows and new tabs
  Result := (targetDisposition in [WOD_NEW_FOREGROUND_TAB, WOD_NEW_BACKGROUND_TAB, WOD_NEW_POPUP, WOD_NEW_WINDOW]);
end;

procedure TMainForm.Chromium1Close(Sender: TObject; const browser: ICefBrowser; var aAction : TCefCloseBrowserAction);
begin
  PostMessage(Handle, CEF_DESTROY, 0, 0);
  aAction := cbaDelay;
end;

procedure TMainForm.BrowserCreatedMsg(var aMessage : TMessage);
begin
  CEFWindowParent1.UpdateSize;
end;

procedure TMainForm.BrowserDestroyMsg(var aMessage : TMessage);
begin
  CEFWindowParent1.Free;
end;

procedure TMainForm.Chromium1KeyEvent(Sender: TObject;
  const browser: ICefBrowser; const event: PCefKeyEvent; osEvent: TCefEventHandle;
  out Result: Boolean);
var
  TempMsg : TMsg;
begin
  Result := False;

  if (event <> nil) and (osEvent <> nil) then
    case osEvent.Message of
      WM_KEYUP :
        begin
          TempMsg := osEvent^;

          HandleKeyUp(TempMsg, Result);
        end;

      WM_KEYDOWN :
        begin
          TempMsg := osEvent^;

          HandleKeyDown(TempMsg, Result);
        end;
    end;
end;

procedure TMainForm.Chromium1PreKeyEvent(Sender: TObject;
  const browser: ICefBrowser; const event: PCefKeyEvent; osEvent: TCefEventHandle;
  out isKeyboardShortcut, Result: Boolean);
begin
  Result := False;

  if (event <> nil) and
     (event.kind in [KEYEVENT_KEYDOWN, KEYEVENT_KEYUP]) and
     (event.windows_key_code = VK_ESCAPE) then
    isKeyboardShortcut := True;
end;

procedure TMainForm.CEFSentinel1Close(Sender: TObject);
begin

end;

procedure TMainForm.FormCloseQuery(Sender: TObject; var CanClose: Boolean);
begin
  CanClose := FCanClose;

  if not(FClosing) then
    begin
      FClosing := True;
      Visible  := False;
      Chromium1.CloseBrowser(True);
    end;
end;

procedure TMainForm.FormCreate(Sender: TObject);
begin
  FCanClose := False;
  FClosing  := False;
end;

procedure TMainForm.FormShow(Sender: TObject);
begin
  Chromium1.DefaultUrl := 'https://www.google.com';

  // GlobalCEFApp.GlobalContextInitialized has to be TRUE before creating any browser
  // If it's not initialized yet, we use a simple timer to create the browser later.
  if not(Chromium1.CreateBrowser(CEFWindowParent1, '')) then Timer1.Enabled := True;
end;

procedure TMainForm.WMMove(var aMessage : TWMMove);
begin
  inherited;

  if (Chromium1 <> nil) then Chromium1.NotifyMoveOrResizeStarted;
end;

procedure TMainForm.WMMoving(var aMessage : TMessage);
begin
  inherited;

  if (Chromium1 <> nil) then Chromium1.NotifyMoveOrResizeStarted;
end;

procedure TMainForm.WMEnterMenuLoop(var aMessage: TMessage);
begin
  inherited;

  if (aMessage.wParam = 0) and (GlobalCEFApp <> nil) then GlobalCEFApp.OsmodalLoop := True;
end;

procedure TMainForm.WMExitMenuLoop(var aMessage: TMessage);
begin
  inherited;

  if (aMessage.wParam = 0) and (GlobalCEFApp <> nil) then GlobalCEFApp.OsmodalLoop := False;
end;

end.