IVideoWindow ClickEvents using Visual C++

Question

0.00/5 (No votes)

See more:

Hi All,

I am using DirectX for previewing Video From Different USB cameras connected to the PC.So I am able to preview them on my main window continuously up to 4 cameras at a time,for this i used IVideoWindow to avoid problem like Active Movie Window am able to preview cameras on my main window.

Now, I am facing a problem like when i click on any of my IVideoWindow it is giving the Coordinates coresponding to IVideoWindow window not to my main Window,For Eg: If i AM displaying First IVideoWindow at [10,100]i.e.,left=10and top=100.if i click on corner of the VideoWindow its Coordinates like [0,0] instead of [10,100].
So I am able to handle the click events but not getting the correct coordinates what I required.

Can anyone help me out from this problem.
Thanks to all in advance.

Posted 29-Apr-11 1:35am

RamyaRaj from NewDelhi

Updated 4-May-11 19:32pm

v3

Add a Solution

2 solutions

Add a Solution

Add your solution here

Treat my content as plain text, not as HTML

Preview 0

…

Existing Members

Sign in to your account

...or Join us

Download, Vote, Comment, Publish.

Your Email
Password
Forgot your password?

Your Email
This email is in use. Do you need your password?
Optional Password

I have read and agree to the Terms of Service and Privacy Policy
Please subscribe me to the CodeProject newsletters

When answering a question please:

Read the question carefully.
Understand that English isn't everyone's first language so be lenient of bad spelling and grammar.
If a question is poorly phrased then either ask for clarification, ignore it, or edit the question and fix the problem. Insults are not welcome.
Don't tell someone to read the manual. Chances are they have and don't get it. Provide an answer or move on to the next question.

Let's work to help developers, not make them feel stupid.

This content, along with any associated source code and files, is licensed under The Code Project Open License (CPOL)

Olivier Levrey · Answer 1 · 2011-04-29T02:46:00

Solution 1

I think you are mixing between client and screen coordinates.

Client coordinates are coordinates relative to the upper-left corner of the window being clicked.
Screen coordinates are coordinates relative to the upper-left corner of the screen.

You can convert the coordinates using PointToClient, PointToScreen methods in .NET, ClientToScreen or ScreenToClient in MFC.
Have also a look to ClientRectangle property in .NET, or GetWindowRect and GetClientRect.

In MSDN, they always say if a point is given in screen or client coordinates.

Posted 29-Apr-11 2:46am

Olivier Levrey

Updated 29-Apr-11 2:47am

v2

Comments

RamyaRaj from NewDelhi 5-May-11 1:30am

hi Olivier Levrey,
Thanks for your reply but my problem is when i click on the window means not not on the main window it is on IVideoWindow what i used for streaming video . If i convert the coordinates using Clienttoscreen method for all IvideoWindow's its giving same coordinates is there any method to convert that coordinates to screen coordinates.Thanks in Advance.

Regards,
RamyaRaj

barneyman 5-May-11 2:35am

have a look at MapWindowPoints then - that should be capable of mapping your IVideoWindow points to the parent window space

RamyaRaj from NewDelhi 5-May-11 7:17am

hi barneyman,
thanks for your solution,but here in MapWindowPoints we need to pass first two arguments as from which Window to which window we need to change the coordinates but here when i click the IvideoWindow i am getting only the information about point where i clicked but not from which IvideoWindow i got this Click
so how can i pass HWnd information to that function can you help me out from this problem.Thanks in Advance

Regards,
RamyaRaj

barneyman 5-May-11 7:21am

IVideoWindow::get_Owner will give you the HWND that the window is currently using

RamyaRaj from NewDelhi 5-May-11 7:26am

yes even i used put_MessageDrain evevt to pass handle of my click events to main window but when i click on IVideoWindow the coordinates what i am getting are corresponding to that window but not to main Hwnd.

barneyman 5-May-11 7:34am

ah ok

Then you're going to have to create a seperate window for each message drain, so you can work out which IVidWnd is informing you

RamyaRaj from NewDelhi 5-May-11 8:21am

ya i created seperate Window for each message but how to know which iVideoWindow is giving this event.When i click it is entering directly into ON_LbuttonDown Function Only i am getting coordinates of the point nothing other than that.

barneyman 5-May-11 8:34am

your child window will have to send a message to the parent window - you can either hijack the WPARAM and add a HIWORD(childid) and pass the WM_LBUTTONDOWN up to flag the source or create a WM_USER message to pass it up

(I assume you're using MFC)

ChildWnd::OnLButtonDown( UINT nFlags, CPoint point)
{
SendMessage(Parent(),WM_LBUTTONDOWN,MAKEDWORD(nflags, childId),MAKEDWORD(point.x,point.y)
}
}

If you're using WTL, it's even easier, you can use window containment to handle each child's message

RamyaRaj from NewDelhi 5-May-11 8:42am

yes i am using MFC only
here ChildWnd means my IVideoWindow

barneyman 5-May-11 8:49am

correct

Parent
Child#1
IVidWnd#1
Child#2
IVidWnd#2
Child#3
IVidWnd#3
Child#4
IVidWnd#4

RamyaRaj from NewDelhi 5-May-11 9:08am

sorry really i dint get you how to pass that message can you send me once again clearly waht i have to do
I dint define any clickevents to my IVideoWindow
how can i define this
ChildWnd::OnLButtonDown( UINT nFlags, CPoint point) {
---------
}

Sorry to trouble you

Regards,
RamyaRaj

RamyaRaj from NewDelhi 7-May-11 8:08am

hi barneyman,
I tried your solution but preview from all cameras are opening in activewindow when i tried to use WS_CLIPSIBLINGS its generating error

when i used
Create(WC_STATIC, "", ws_child | ws_visible, where, parent, id);
what you suggested me its providing error like create doesnot take 6 parameters so i did in the following way
CWnd* pWnd = new CWnd;
pWnd->Create(_T("STATIC"), "", WS_CHILD | WS_VISIBLE, where, parent, id);
wheather this may be a cause for opening in Active window mode

And also
when to call this
void OnLButton(UINT flags, Point where)

in our child window class
or it will automatically enters into it when we click on IVideoWindow because of message drain.Can you please help me out from this problem.Whether I am going wrong anywhere.Thanks in advance.

Regards,
RamyaRaj.

RamyaRaj from NewDelhi 5-May-11 8:26am

these are few lines of code wat i am using

pGraphList[CamNo]->QueryInterface( IID_IVideoWindow, (void**) &pVidWin[CamNo]);

pVidWin[CamNo]->put_Owner((OAHWND)hWnd);
pVidWin[CamNo]->put_WindowStyle(WS_CHILD | WS_CLIPSIBLINGS);

pVidWin[CamNo]->put_MessageDrain( (OAHWND)hWnd ); pVidWin[CamNo]->put_Visible(OATRUE);
pVidWin[CamNo]->SetWindowForeground(-1);

Regards,
RamyaRaj.

Olivier Levrey 5-May-11 8:31am

I am glad I can follow your conversation guys, but my email box is about to explode ;) Could you please put comments somewhere else? Thanks :)

RamyaRaj from NewDelhi 5-May-11 8:17am

when i am using MapWindowPoints it is not accepting 4 parameters as argument even i included winuser.h windows.h user32.lib also linked anything else i have to add to use this MapWindowPoints

Regards,
RamyaRaj

Olivier Levrey 5-May-11 4:16am

Normally this should work on any window you click. ClientToScreen is the function to convert client coordinates to screen coordinates. But make sure you are calling this method from the window which fired the click event, otherwise the convertion will convert from the wrong window.

RamyaRaj from NewDelhi 5-May-11 7:24am

Hi Olivier Levrey,
I am calling this ClientToScreen function in LButtonDown function of my main Dialog.when i click IvideoWindow i am getting only the information about point where i clicked but not from which IvideoWindow i got this Click.I am Creating Seperate handles to all IVideoWindows.I am using put_MessageDrain event to pass message handlings from IvideoWindow to my main Dialog Message events like LButtonDown,OnMouseMove,RButtonDown etc.,so wen i left click on IvideoWindow it passes message to ON_LButtonDown Function of my MainDialog.Can you Help me out from this Problem Thanks in Advance.

Regards,
RamyaRaj.

Olivier Levrey 5-May-11 7:36am

I am affraid I can't help you further since I don't know IVideoWindows interface. I thought your problem was pure MFC, but it seems it is also related to DirectX. Barneyman can maybe help you more.

RamyaRaj from NewDelhi 5-May-11 8:38am

ok Olivier Levrey thanks for your help if you got any information about this can you please add your solution to me.Thanks for your help.

Regards,
Ramya Raj.

barneyman · Answer 2 · 2011-05-05T03:42:00

Solution 2

At the moment, I think, inferring from your posts, that you have a single CWnd window, and then you are telling each IVideoWindow where to position itself on that window i.e.

pseudocode

vidWindow[0..3]->put_Owner(*this);

// assume this hwnd is 0,0,100,100
vidWindow[0]->SetWindowPosition(0,0,50,50);
vidWindow[1]->SetWindowPosition(50,0,50,50);
vidWindow[2]->SetWindowPosition(0,50,50,50);
vidWindow[3]->SetWindowPosition(50,50,50,50);

vidWindow[0..3]->put_MessageDrain(*this);

this means you can't determine which video window is telling you about a click

If you create a child CWnd window for each IVidWnd you have more chance to work out what's happening

again, pseudocode

class ChildVideoWindow : public CWnd
{
public
 Create(IVideoWindow *vw, RECT &where, UINT id, Cwnd *parent):m_id(id) 
 {
   Create(WC_STATIC, "", ws_child | ws_visible, where, parent, id);
   vw->put_Owner(*this);
   vw->put_MessageDrain(*this);
 }

 void OnLButton(UINT flags, Point where)
 {
   GetParent()->SendMessage( WM_LBUTTONDOWN, MAKDWORD(flags,m_id), MAKEDWORD(where.x,where.y);
 }

protected:

UINT m_id;

};

// in your Parent CWnd


 ChildVideoWindow childVideos[4];
 childVideos[0..3].Create(vidWindow[0..3],rect0..3,0..3, this);


ParentCWnd::OnLButton(UINT flags, Point where)
{
 int videoWindowThisMessageCameFrom=HIWORD(flags);
 ....

}

Posted 5-May-11 3:42am

barneyman

Comments

barneyman 7-May-11 20:56pm

hi barneyman,
I tried your solution but preview from all cameras are opening in activewindow when i tried to use WS_CLIPSIBLINGS its generating error

when i used
Create(WC_STATIC, "", ws_child | ws_visible, where, parent, id);
what you suggested me its providing error like create doesnot take 6 parameters so i did in the following way
CWnd* pWnd = new CWnd;
pWnd->Create(_T("STATIC"), "", WS_CHILD | WS_VISIBLE, where, parent, id);
wheather this may be a cause for opening in Active window mode

And also
when to call this
void OnLButton(UINT flags, Point where)

in our child window class
or it will automatically enters into it when we click on IVideoWindow because of message drain.Can you please help me out from this problem.Whether I am going wrong anywhere.Thanks in advance.

Regards,
RamyaRaj.

barneyman 7-May-11 21:01pm

it's important for you to make each child window the parent of each videowindow

The videowindow feeds the message pump of the child window, which is how you get the Childs OnLBButton

RamyaRaj from NewDelhi 9-May-11 1:11am

hi barneyman,

Why these are opening in Active movie window how can I solve this problem.

Regards,
RamyaRaj.

barneyman 9-May-11 1:20am

i don't understand what 'active movie window' means

Are you giving each of the ivideowindows their own window, using put_Owner?

RamyaRaj from NewDelhi 9-May-11 2:27am

IT IS LIKE OPENING THE CAMERA PREVIEW IN A SEPERATE WINDOW NOT STICKING ON TO MY MAIN CWnd

barneyman 9-May-11 2:38am

that is the solution to your problem isn't it?

Now you'll know which of the child windows is raising the LButton event

RamyaRaj from NewDelhi 9-May-11 3:09am

No ,It should stick to my window it should not pop up like a new window.If it stick to my window then the interface is like preview is on my main CWnd not on separate window.So when i click on any Video window i need to make that particular camera as active camera and i need to do further process based on that.

So when i use the following code i am able to stick the VideoWindow to my Main CWnd

pGraphList[CamNo]->QueryInterface( IID_IVideoWindow, (void**) &pVidWin[CamNo]); pVidWin[CamNo]->put_Owner((OAHWND)hWnd); pVidWin[CamNo]->put_WindowStyle(WS_CHILD | WS_CLIPSIBLINGS); pVidWin[CamNo]->put_MessageDrain( (OAHWND)hWnd ); pVidWin[CamNo]->put_Visible(OATRUE); pVidWin[CamNo]->SetWindowForeground(-1);

But I am getting problem at click events.

Regards,
RamyaRaj.

barneyman 9-May-11 3:18am

i understand - so you're giving all the cameras the same hwnd owner and the same message drain, you won't know which video window was clicked ... you're back to your original problem

RamyaRaj from NewDelhi 9-May-11 3:48am

yes your right

barneyman 9-May-11 3:50am

if you don't want to use child windows for the drain or (the drain and the owner), I don't know how you can resolve it

RamyaRaj from NewDelhi 9-May-11 5:19am

Can anyone help me out from this problem still i dint get any solution for this.Thanks to all in advance

Regards,
RamyaRaj.

RamyaRaj from NewDelhi 24-May-11 6:11am

Hi to all,
Can anyone please help me out from this problem still I dint find any solution to this.If I am not able to convey my question properly ,Please can anyone help me how to post this question.

Thanks to all in Advance.

Regards,
RamyaRaj.