CEF4Delphi/demos/Lazarus_Windows/PopupBrowser2/uMainForm.pas
2023-01-07 15:53:04 +01:00

384 lines
13 KiB
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// ************************************************************************
// ***************************** CEF4Delphi *******************************
// ************************************************************************
//
// CEF4Delphi is based on DCEF3 which uses CEF to embed a chromium-based
// browser in Delphi applications.
//
// The original license of DCEF3 still applies to CEF4Delphi.
//
// For more information about CEF4Delphi visit :
// https://www.briskbard.com/index.php?lang=en&pageid=cef
//
// Copyright © 2023 Salvador Diaz Fau. All rights reserved.
//
// ************************************************************************
// ************ vvvv Original license and comments below vvvv *************
// ************************************************************************
(*
* Delphi Chromium Embedded 3
*
* Usage allowed under the restrictions of the Lesser GNU General Public License
* or alternatively the restrictions of the Mozilla Public License 1.1
*
* Software distributed under the License is distributed on an "AS IS" basis,
* WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License for
* the specific language governing rights and limitations under the License.
*
* Unit owner : Henri Gourvest <hgourvest@gmail.com>
* Web site : http://www.progdigy.com
* Repository : http://code.google.com/p/delphichromiumembedded/
* Group : http://groups.google.com/group/delphichromiumembedded
*
* Embarcadero Technologies, Inc is not permitted to use or redistribute
* this source code without explicit permission.
*
*)
unit uMainForm;
{$I cef.inc}
interface
uses
Windows, Messages, SysUtils, Variants, Classes, Graphics,
Controls, Forms, Dialogs, StdCtrls, ExtCtrls, SyncObjs,
uCEFChromium, uCEFWindowParent, uCEFInterfaces, uCEFConstants, uCEFTypes, uChildForm,
uCEFWinControl, uCEFChromiumEvents, uCEFSentinel;
const
CEF_CREATENEXTCHILD = WM_APP + $A50;
CEF_CHILDDESTROYED = WM_APP + $A51;
type
{ TMainForm }
TMainForm = class(TForm)
AddressPnl: TPanel;
AddressEdt: TEdit;
ApplicationProperties1: TApplicationProperties;
GoBtn: TButton;
Timer1: TTimer;
Chromium1: TChromium;
CEFWindowParent1: TCEFWindowParent;
procedure CEFSentinel1Close(Sender: TObject);
procedure GoBtnClick(Sender: TObject);
procedure Timer1Timer(Sender: TObject);
procedure FormShow(Sender: TObject);
procedure FormCreate(Sender: TObject);
procedure FormDestroy(Sender: TObject);
procedure FormCloseQuery(Sender: TObject; var CanClose: Boolean);
procedure Chromium1AfterCreated(Sender: TObject; const browser: ICefBrowser);
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 Chromium1BeforeClose(Sender: TObject; const browser: ICefBrowser);
procedure Chromium1Close(Sender: TObject; const browser: ICefBrowser; var aAction: TCefCloseBrowserAction);
protected
FChildForm : TChildForm;
FCriticalSection : TCriticalSection;
FCanClose : boolean; // Set to True in TChromium.OnBeforeClose
FClosingMainForm : boolean; // Set to True in the CloseQuery event.
FClosingChildren : boolean; // Set to True in the CloseQuery event.
function GetPopupChildCount : integer;
procedure ClosePopupChildren;
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 CreateNextChildMsg(var aMessage : TMessage); message CEF_CREATENEXTCHILD;
procedure ChildDestroyedMsg(var aMessage : TMessage); message CEF_CHILDDESTROYED;
public
function CreateClientHandler(var windowInfo : TCefWindowInfo; var client : ICefClient; const targetFrameName : string; const popupFeatures : TCefPopupFeatures) : boolean;
property PopupChildCount : integer read GetPopupChildCount;
end;
var
MainForm: TMainForm;
procedure CreateGlobalCEFApp;
implementation
{$R *.lfm}
uses
uCEFApplication, uCEFMiscFunctions;
// This is demo shows how to create popup windows in CEF.
// You need to understand the SimpleBrowser2 demo completely before trying to understand this demo.
// When TChromium needs to show a new popup window it executes TChromium.OnBeforePopup.
// VCL components *MUST* be created and destroyed in the main thread but CEF executes the
// TChromium.OnBeforePopup in a different thread.
// For this reason this demo creates a hidden popup form (TChildForm) in case CEF needs to show a popup window.
// TChromium.OnBeforePopup calls TChildForm.CreateClientHandler to initialize some parameters and create the new ICefClient.
// After that, it sends a CEF_CREATENEXTCHILD message to show the popup form and create a new one.
// All the child forms must be correctly destroyed before closing the main form. Read the code comments in uChildForm.pas
// to know how the popup windows are destroyed.
// The main form sends a WM_CLOSE to all active popup forms and waits until all of them have sent a CEF_CHILDDESTROYED message.
// Destruction steps
// =================
// 1. FormCloseQuery sets CanClose to FALSE and it closes all child forms.
// 2. When all the child forms are closed then FormCloseQuery is triggered again, sets CanClose to FALSE calls TChromium.CloseBrowser which triggers the TChromium.OnClose event.
// 3. TChromium.OnClose sends a CEFBROWSER_DESTROY message to destroy CEFWindowParent1 in the main thread, which triggers the TChromium.OnBeforeClose event.
// 4. TChromium.OnBeforeClose sets FCanClose := True and sends WM_CLOSE to the form.
procedure CreateGlobalCEFApp;
begin
GlobalCEFApp := TCefApplication.Create;
GlobalCEFApp.EnableHighDPISupport := True;
//GlobalCEFApp.LogFile := 'cef.log';
//GlobalCEFApp.LogSeverity := LOGSEVERITY_VERBOSE;
end;
procedure TMainForm.FormCloseQuery(Sender: TObject; var CanClose: Boolean);
begin
FClosingChildren := True;
Visible := False;
if (PopupChildCount > 0) then
begin
ClosePopupChildren;
CanClose := False;
end
else
begin
CanClose := FCanClose;
if not(FClosingMainForm) then
begin
FClosingMainForm := True;
Chromium1.CloseBrowser(True);
end;
end;
end;
procedure TMainForm.FormCreate(Sender: TObject);
begin
FClosingChildren := False;
FClosingMainForm := False;
FCanClose := False;
FCriticalSection := TCriticalSection.Create;
Chromium1.DefaultURL := AddressEdt.Text;
Chromium1.Options.BackgroundColor := CefColorSetARGB($FF, $FF, $FF, $FF);
end;
procedure TMainForm.FormDestroy(Sender: TObject);
begin
FreeAndNil(FCriticalSection);
end;
procedure TMainForm.FormShow(Sender: TObject);
begin
// You *MUST* call CreateBrowser to create and initialize the browser.
// This will trigger the AfterCreated event when the browser is fully
// initialized and ready to receive commands.
// 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.Chromium1AfterCreated(Sender: TObject; const browser: ICefBrowser);
begin
// Now the browser is fully initialized we can send a message to the main form to load the initial web page.
PostMessage(Handle, CEF_AFTERCREATED, 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
case targetDisposition of
WOD_NEW_FOREGROUND_TAB,
WOD_NEW_BACKGROUND_TAB,
WOD_NEW_WINDOW : Result := True; // For simplicity, this demo blocks new tabs and new windows.
WOD_NEW_POPUP : Result := not(CreateClientHandler(windowInfo, client, targetFrameName, popupFeatures));
else Result := False;
end;
end;
function TMainForm.CreateClientHandler(var windowInfo : TCefWindowInfo;
var client : ICefClient;
const targetFrameName : string;
const popupFeatures : TCefPopupFeatures) : boolean;
begin
try
FCriticalSection.Acquire;
Result := (FChildForm <> nil) and
FChildForm.CreateClientHandler(windowInfo, client, targetFrameName, popupFeatures) and
PostMessage(Handle, CEF_CREATENEXTCHILD, 0, 0);
finally
FCriticalSection.Release;
end;
end;
function TMainForm.GetPopupChildCount : integer;
var
i : integer;
TempForm : TCustomForm;
begin
Result := 0;
i := pred(screen.CustomFormCount);
while (i >= 0) do
begin
TempForm := screen.CustomForms[i];
// Only count the fully initialized child forms and not the one waiting to be used.
if (TempForm is TChildForm) and
TChildForm(TempForm).ClientInitialized then
inc(Result);
dec(i);
end;
end;
procedure TMainForm.ClosePopupChildren;
var
i : integer;
TempForm : TCustomForm;
begin
i := pred(screen.CustomFormCount);
while (i >= 0) do
begin
TempForm := screen.CustomForms[i];
// Only send WM_CLOSE to fully initialized child forms.
if (TempForm is TChildForm) and
TChildForm(TempForm).ClientInitialized and
not(TChildForm(TempForm).Closing) then
PostMessage(TChildForm(TempForm).Handle, WM_CLOSE, 0, 0);
dec(i);
end;
end;
procedure TMainForm.BrowserCreatedMsg(var aMessage : TMessage);
begin
FChildForm := TChildForm.Create(self);
Caption := 'Popup Browser';
AddressPnl.Enabled := True;
end;
procedure TMainForm.BrowserDestroyMsg(var aMessage : TMessage);
begin
CEFWindowParent1.Free;
end;
procedure TMainForm.CreateNextChildMsg(var aMessage : TMessage);
begin
try
FCriticalSection.Acquire;
if (FChildForm <> nil) then
begin
//FChildForm.ApplyPopupFeatures;
//FChildForm.Show;
PostMessage(FChildForm.Handle, CEF_SHOWCHILD, 0, 0);
end;
FChildForm := TChildForm.Create(self);
finally
FCriticalSection.Release;
end;
end;
procedure TMainForm.ChildDestroyedMsg(var aMessage : TMessage);
begin
if FClosingChildren and (PopupChildCount = 0) then Close;
end;
procedure TMainForm.GoBtnClick(Sender: TObject);
begin
// This will load the URL in the edit box
Chromium1.LoadURL(AddressEdt.Text);
end;
procedure TMainForm.CEFSentinel1Close(Sender: TObject);
begin
end;
procedure TMainForm.Chromium1BeforeClose(Sender: TObject; const browser: ICefBrowser);
begin
FCanClose := True;
PostMessage(Handle, WM_CLOSE, 0, 0);
end;
procedure TMainForm.Chromium1Close(Sender: TObject; const browser: ICefBrowser;
var aAction: TCefCloseBrowserAction);
begin
PostMessage(Handle, CEF_DESTROY, 0, 0);
aAction := cbaDelay;
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.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.