In Delphi rad studio 10.3, I use cef4delphi to call chromium.Loadurl() or chromium.Browser.Mainframe.Loadurl(), which will cause the top of the program. How can I solve it
procedure TfrmFatchView.Chromium_OnLoadingStateChange(Sender: TObject; const
browser: ICefBrowser; isLoading, canGoBack, canGoForward: Boolean);
begin
FChromium.DefaultWindowInfoExStyle := FChromium.DefaultWindowInfoExStyle;
end;
procedure TfrmFatchView.Chromium_OnSetFocus(Sender: TObject; const browser:
ICefBrowser; source: TCefFocusSource; out Result: Boolean);
begin
Result := True;
end;
Related
I have an event procedure that checks the OnKeyUp key press for two objects/controls (TNewEdit and TNewComboBox). Both objects need to be completed before a TNewButton gets enabled.
However, I cannot find a way to know how to get the type of the Sender: TObject, if that is TNewEdit or TNewComboBox.
Anyone can help?
You should not need to know the type/class for anything.
Such a need is a sign of a bad design.
If the handling of the event is different for each type/class, create a separate handler for each.
If part of the handling is common, call the common handler from the specific handlers.
var
Edit: TNewEdit;
ComboBox: TNewComboBox;
procedure CommonKeyUp(Sender: TObject; var Key: Word; Shift: TShiftState);
begin
Log('Common handling');
end;
procedure EditKeyUp(Sender: TObject; var Key: Word; Shift: TShiftState);
begin
Log('Edit key up');
CommonKeyUp(Sender, Key, Shift);
end;
procedure ComboBoxKeyUp(Sender: TObject; var Key: Word; Shift: TShiftState);
begin
Log('Combo box key up');
CommonKeyUp(Sender, Key, Shift);
end;
procedure InitializeWizard();
begin
{ ... }
Edit.OnKeyUp := #EditKeyUp;
Combobox.OnKeyUp := #ComboBoxKeyUp;
end;
Though as you actually have two controls, you probably want to distinguish, what control raised the event.
That's, what the Sender argument is for. The following code shows how to use it. But again, in general, this is not the right way to go.
var
Edit: TNewEdit;
ComboBox: TNewComboBox;
procedure ControlKeyUp(Sender: TObject; var Key: Word; Shift: TShiftState);
begin
if Sender = Edit then
begin
Log('Edit key up');
end
else
if Sender = ComboBox then
begin
Log('Combo box key up');
end
else
begin
Log('Other key up');
end;
end;
procedure InitializeWizard();
begin
{ ... }
Edit.OnKeyUp := #ControlKeyUp;
Combobox.OnKeyUp := #ControlKeyUp;
end;
Though still I do not understand, what you need this for.
You have to check both controls every time, so why do you need to know, what control, was the one that changed?
Also, to detect a change, do not use OnKeyUp, use OnChange. That way you capture all changes (key press, drag&drop, copy&paste, anything).
var
Edit: TNewEdit;
ComboBox: TNewComboBox;
Button: TNewButton;
procedure ControlChange(Sender: TObject);
begin
Button.Enabled := (Edit.Text <> '') and (ComboBox.Text <> '');
end;
procedure InitializeWizard();
begin
{ ... }
Edit.OnChange := #ControlChange;
Combobox.OnChange := #ControlChange;
end;
Application has a Login form and a Main form.
Applications DPR file has code to load Login form first, and when Login form returns successful login, then Main form is created and loaded.
When user logs out via a menu command in Main form, it should close the Main form and load the Login form.
Application exits only when user selects Exit in the Main form (or when user Cancels out of the Login form).
Using code in the application's DPR file, is it possible to code this?
Here is the code that presently exists:
program H;
uses
Forms,
SysUtils,
Registry,
MidasLib,
Dialogs,
Controls,
uDatamod in 'uDatamod.pas' {datamod: TDataModule} ,
uMain in 'uMain.pas' {fMain} ,
uMtlUpd in 'uMtlUpd.pas' {fMtlUpd} ,
uReportPrv in 'uReportPrv.pas' {fReportPrv} ,
uCamera in 'uCamera.pas' {fCamera} ,
uConfig in 'uConfig.pas' {fConfig} ,
uFuncs in 'uFuncs.pas',
uLogin in 'uLogin.pas' {fLogin} ,
uAdmin in 'uAdmin.pas' {fAdmin};
// MidasLib is required.
{$R *.res}
begin
Application.Initialize;
Application.MainFormOnTaskbar := True;
Application.Title := 'HTech';
if ((ParamCount = 1) and (UpperCase(ParamStr(1)) = '/CONFIG')) or
(getHServerHostName = EmptyStr) then
begin
Application.CreateForm(TfConfig, fConfig);
Application.Run;
end
else
begin
if not testHServerConnection then
begin
ShowMessage('Error: Could not connect to HServer');
Exit;
end;
Application.CreateForm(Tdatamod, Datamod);
while not TerminateApplicationFlag do
begin
fLogin := TfLogin.Create(Application);
try
if fLogin.ShowModal = mrOk then
begin
LoggedInEmployeeID := fLogin.FEmployeeID;
LoggedInEmployeeNm := fLogin.edtFirstName.Text + ' ' +
fLogin.edtLastName.Text;
AdminLogin := fLogin.FAdminUser;
FinanceLogin := fLogin.FFinanceUser;
end
else
begin
FreeAndNil(fLogin);
FreeAndNil(Datamod);
Exit;
end;
finally
// FreeAndNil(fLogin);
end;
if AdminLogin then
Application.CreateForm(TfAdmin, fAdmin)
else
begin
FreeAndNil(fLogin);
if not Assigned(fMain) then
Application.CreateForm(TfMain, fMain);
fMain.FHServerHost := getHServerHostName;
end;
Application.Run;
end;
end;
end.
The problem with the above code is that after one iteration (after user performs Logout in Main form), the application exits (control is returned to the operating system) because " fLogin.ShowModal " exits without showing the Login form.
Here is the code from the Main form:
Procedure LogoutProcedure;
begin
TerminateApplicationFlag := False;
Close;
end;
Procedure ExitProcedure;
begin
TerminateApplicationFlag := True;
Close;
end;
I'm stuck with this and would appreciate any advice or corrections in getting it to work.
Thank you in advance.
Regards,
Steve Faleiro
Maybe this very simple solution is sufficient:
The project file:
program Project1;
uses
Forms,
FMain in 'FMain.pas' {MainForm},
FLogin in 'FLogin.pas' {LoginForm};
{$R *.res}
var
MainForm: TMainForm;
begin
Application.Initialize;
Application.CreateForm(TMainForm, MainForm);
Login;
Application.Run;
end.
The main form:
unit FMain;
interface
uses
Classes, Controls, Forms, StdCtrls, FLogin;
type
TMainForm = class(TForm)
LogoutButton: TButton;
procedure LogoutButtonClick(Sender: TObject);
end;
implementation
{$R *.dfm}
procedure TMainForm.LogoutButtonClick(Sender: TObject);
begin
Login;
end;
end.
And the login form:
unit FLogin;
interface
uses
Classes, Controls, Forms, StdCtrls;
type
TLoginForm = class(TForm)
LoginButton: TButton;
CancelButton: TButton;
procedure FormCreate(Sender: TObject);
end;
procedure Login;
implementation
{$R *.dfm}
procedure Login;
begin
with TLoginForm.Create(nil) do
try
Application.MainForm.Hide;
if ShowModal = mrOK then
Application.MainForm.Show
else
Application.Terminate;
finally
Free;
end;
end;
procedure TLoginForm.FormCreate(Sender: TObject);
begin
LoginButton.ModalResult := mrOK;
CancelButton.ModalResult := mrCancel;
end;
end.
Now, this answer works here, quite well with Delphi 7, but I suspect problems with more recent versions were Application.MainFormOnTaskbar and Application.ShowMainForm are True by default. When so, try to set them to False.
i try to fix up my activex project and i had errors , i have 2 forms in my activex project first form hold tmemo and button to call second form as parented form every thing works fine till now but i cannot set any record from second form to first form control always get access violation so i decided to show result before set tmemo.text control in the first form and actually result is showing but but cannot be set into the first form here is my project code
unit main1;
{$WARN SYMBOL_PLATFORM OFF}
interface
uses
Windows, Messages, SysUtils, Classes, Graphics, Controls, Forms, Dialogs,
ActiveX, AxCtrls, embed_TLB, StdVcl, Vcl.StdCtrls;
type
Tform1 = class(TForm, Iform1)
Button1: TButton;
Memo1: TMemo;
procedure Button1Click(Sender: TObject);
procedure FormCreate(Sender: TObject);
private
{ Private declarations }
protected
{ Protected declarations }
public
{ Public declarations }
procedure showEmo(L,T:Integer);
end;
var
Form1 : Tform1;
implementation
uses ComObj, ComServ, main2;
{$R *.DFM}
{ Tform1 }
procedure Tform1.Button1Click(Sender: TObject);
var
Rect: TRect;
begin
GetWindowRect(Self.button1.Handle, Rect);
showEmo(Rect.Left + 70,(Rect.Top - 290));
end;
procedure Tform1.FormCreate(Sender: TObject);
begin
Form2 := TForm2.Createparented(0);
end;
procedure TForm1.showEmo(L,T:Integer);
var
Rect: TRect;
begin
try
GetWindowRect(button1.Handle, Rect);
begin
Form2.FormStyle := fsStayOnTop;
end;
Form2.Left := L;//Rect.Left;
Form2.top := T;//Rect.Top - emo.Height;
finally
Form2.Visible := not (Form2.visible);
end;
end;
initialization
TActiveFormFactory.Create(
ComServer,
TActiveFormControl,
Tform1,
Class_form1,
0,
'',
OLEMISC_SIMPLEFRAME or OLEMISC_ACTSLIKELABEL,
tmApartment);
end.
Form 2
unit main2;
interface
uses
Winapi.Windows, Winapi.Messages, System.SysUtils, System.Variants, System.Classes, Vcl.Graphics,
Vcl.Controls, Vcl.Forms, Vcl.Dialogs, Vcl.OleCtrls, SHDocVw_EWB, EwbCore,
EmbeddedWB, MSHTML_EWB, Vcl.StdCtrls;
type
TForm2 = class(TForm)
ewbpage: TEmbeddedWB;
load: TMemo;
procedure FormCreate(Sender: TObject);
procedure ewbpageBeforeNavigate2(ASender: TObject; const pDisp: IDispatch;
var URL, Flags, TargetFrameName, PostData, Headers: OleVariant;
var Cancel: WordBool);
private
{ Private declarations }
public
{ Public declarations }
end;
var
Form2: TForm2;
implementation
uses main1;
{$R *.dfm}
procedure TForm2.ewbpageBeforeNavigate2(ASender: TObject; const pDisp: IDispatch;
var URL, Flags, TargetFrameName, PostData, Headers: OleVariant;
var Cancel: WordBool);
var
MousePos: TPoint;
HtmlElement: IHTMLElement;
iHTMLDoc: IHtmlDocument2;
begin
if Pos('#sm',URL)>0 then
begin
if Supports(ewbpage.Document, IHtmlDocument2, iHTMLDoc) then
begin
if GetCursorPos(MousePos) then
begin
MousePos := ewbpage.ScreenToClient(MousePos);
HtmlElement := iHTMLDoc.ElementFromPoint(MousePos.X, MousePos.Y);
if Assigned(HtmlElement) then
showmessage(HtmlElement.getAttribute('id', 0));
form1.Memo1.Text := HtmlElement.getAttribute('id', 0);
Cancel := True;
Self.Close;
end;
end;
end;
end;
procedure TForm2.FormCreate(Sender: TObject);
begin
ewbpage.LoadFromStrings(load.Lines);
end;
end.
and the question is why i get this error
Access violation at address 07C734FC in module 'EMBEDA~1.OCX'. Read of
address 000003B4.
at this line
form1.Memo1.Text := HtmlElement.getAttribute('id', 0);
why i cannot set result from second form to first form ? what i did wrong here is the full project for better understand
http://www.mediafire.com/download/zn7hzoxze2390a3/embeddedactivex.zip
You will see this issue once you start to format your code properly
procedure TForm2.ewbpageBeforeNavigate2(ASender: TObject; const pDisp: IDispatch;
var URL, Flags, TargetFrameName, PostData, Headers: OleVariant;
var Cancel: WordBool);
var
MousePos: TPoint;
HtmlElement: IHTMLElement;
iHTMLDoc: IHtmlDocument2;
begin
if Pos('#sm',URL)>0 then
begin
if Supports(ewbpage.Document, IHtmlDocument2, iHTMLDoc) then
begin
if GetCursorPos(MousePos) then
begin
MousePos := ewbpage.ScreenToClient(MousePos);
HtmlElement := iHTMLDoc.ElementFromPoint(MousePos.X, MousePos.Y);
// if we have a valid HtmlElement ...
if Assigned(HtmlElement)
then // show a message
showmessage(HtmlElement.getAttribute('id', 0));
// now we do not care about if HtmlElement is valid or not
form1.Memo1.Text := HtmlElement.getAttribute('id', 0);
Cancel := True;
Self.Close;
end;
end;
end;
end;
To only solve your current access violation you simply put a begin end block around all the lines that will use HtmlElement.
HtmlElement := iHTMLDoc.ElementFromPoint( MousePos.X, MousePos.Y );
if Assigned( HtmlElement )
then
begin
showmessage( HtmlElement.getAttribute( 'id', 0 ) );
form1.Memo1.Text := HtmlElement.getAttribute( 'id', 0 );
end;
But there are some more issues in your code. You should not use the global variables form1 and form2. Instead pass the form instance to the created TForm2 instance or even better a callback method.
Guys, I'd like if anyone knows any event or method that I can intercept when all MDI forms were closed.
Example:
I want to implement an event in my main form where when I close all MDI forms, such an event was triggered.
Grateful if anyone can help.
MDI child forms (in fact any form), while being destroyed, will notify the main form. You can use this notification mechanism. Example:
type
TForm1 = class(TForm)
..
protected
procedure Notification(AComponent: TComponent; Operation: TOperation);
override;
..
procedure TForm1.Notification(AComponent: TComponent; Operation: TOperation);
begin
inherited;
if (Operation = opRemove) and (AComponent is TForm) and
(TForm(AComponent).FormStyle = fsMDIChild) and
(MDIChildCount = 0) then begin
// do work
end;
end;
Catch the WM_MDIDESTROY message send to the MDI client window:
type
TForm1 = class(TForm)
procedure FormCreate(Sender: TObject);
procedure FormDestroy(Sender: TObject);
private
FOldClientWndProc: TFarProc;
procedure NewClientWndProc(var Message: TMessage);
end;
...
procedure TForm1.FormCreate(Sender: TObject);
begin
if FormStyle = fsMDIForm then
begin
HandleNeeded;
FOldClientWndProc := Pointer(GetWindowLong(ClientHandle, GWL_WNDPROC));
SetWindowLong(ClientHandle, GWL_WNDPROC,
Integer(MakeObjectInstance(NewClientWndProc)));
end;
end;
procedure TForm1.FormDestroy(Sender: TObject);
begin
SetWindowLong(ClientHandle, GWL_WNDPROC, Integer(FOldClientWndProc));
end;
procedure TForm1.NewClientWndProc(var Message: TMessage);
begin
if Message.Msg = WM_MDIDESTROY then
if MDIChildCount = 1 then
// do work
with Message do
Result := CallWindowProc(FOldClientWndProc, ClientHandle, Msg, WParam,
LParam);
end;
You can have the MainForm assign an OnClose or OnDestroy event handler to each MDI child it creates. Each time an MDI client is closed/destroyed, the handler can check if any more MDI child forms are still open, and if not then do whatever it needs to do.
procedure TMainForm.ChildClosed(Sender: TObject; var Action: TCloseAction);
begin
Action := caFree;
// the child being closed is still in the MDIChild list as it has not been freed yet...
if MDIChildCount = 1 then
begin
// do work
end;
end;
Or:
const
APPWM_CHECK_MDI_CHILDREN = WM_APP + 1;
procedure TMainForm.ChildDestroyed(Sender: TObject);
begin
PostMessage(Handle, APPWM_CHECK_MDI_CHILDREN, 0, 0);
end;
procedure TMainForm.WndProc(var Message: TMessage);
begin
if Message.Msg = APPWM_CHECK_MDI_CHILDREN then
begin
if MDIChildCount = 0 then
begin
// do work
end;
Exit;
end;
inherited;
end;
I have a program where it will not start minimized and shows a very small window on the dekstop.
Image: http://i.imgur.com/j8xus.jpg
Code:
program:
program Project4;
uses
Forms,
Unit4 in 'Unit4.pas' {Form4};
{$R *.res}
begin
Application.Initialize;
Application.MainFormOnTaskbar := false;
Application.ShowMainForm:=false;
Application.CreateForm(TForm4, Form4);
Application.Run;
end.
unit:
unit Unit4;
interface
uses
Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
Dialogs, AppEvnts, ExtCtrls, Menus;
type
TForm4 = class(TForm)
TrayIcon1: TTrayIcon;
ApplicationEvents1: TApplicationEvents;
PopupMenu1: TPopupMenu;
Exit1: TMenuItem;
procedure TrayIcon1DblClick(Sender: TObject);
procedure ApplicationEvents1Minimize(Sender: TObject);
procedure ApplicationEvents1Restore(Sender: TObject);
procedure FormCloseQuery(Sender: TObject; var CanClose: Boolean);
procedure FormCreate(Sender: TObject);
procedure Exit1Click(Sender: TObject);
private
{ Private declarations }
fCanClose: Boolean;
public
{ Public declarations }
end;
var
Form4: TForm4;
implementation
{$R *.dfm}
procedure TForm4.ApplicationEvents1Minimize(Sender: TObject);
begin
Hide();
WindowState := wsMinimized;
end;
procedure TForm4.ApplicationEvents1Restore(Sender: TObject);
begin
Show();
WindowState := wsNormal;
application.Bringtofront;
end;
procedure TForm4.Exit1Click(Sender: TObject);
begin
fcanclose:=true;
close;
end;
procedure TForm4.FormCloseQuery(Sender: TObject; var CanClose: Boolean);
begin
if not fCanClose then
begin
hide;
windowstate:=wsminimized;
CanClose:=false;
end
else
CanCLose:=True;
end;
procedure TForm4.FormCreate(Sender: TObject);
begin
fCanClose:=FALSE;
end;
procedure TForm4.TrayIcon1DblClick(Sender: TObject);
begin
if (windowstate = wsminimized) then
begin
Show;
windowstate := wsnormal;
application.BringToFront;
end
else
begin
hide;
windowstate:=wsminimized;
end;
end;
end.
I created your project and had the same problems until I changed the following line of code to True:
Application.MainFormOnTaskbar := True;
Now the app seems to work just fine without an minimizing to the bottom left corner of the desktop before it is hidden.