How to set up BrowserControl to send an event when it closes

[revbob]

I wrote about a Pandora node a while back, and it works just ducky except for one thing: when I close the browser window, the player (an embedded Flash control) keeps on playing invisibly.

Here's how I create the window:

Code: Select all

Sub OpenInPopup(Node)

  Dim Form, BrowserControl, Command
  Command = Node.CustomData
  Set Form = SDB.UI.NewForm
  Form.Common.SetRect 100, 100, 900, 700
  Form.Caption = Command

  Set BrowserControl = SDB.UI.NewActiveX(Form, "Shell.Explorer")
  BrowserControl.Common.Align = 5         ' Fill all client rectangle
  BrowserControl.Interf.Navigate Command  ' Go to the specified URL
  Form.Common.Visible = True
  SDB.Objects("Pandora Window") = Form    ' Make the window hang about
  Script.RegisterEvent Form, "OnShutdown", "FormClose"

End Sub

When I put a MessageBox in my FormClose sub to indicate receipt of the event, neither closing the browser window nor closing MM activates , so I suspect the problem is where I hung the BrowserControl. Here's the sub, just in case the fault is there:

Code: Select all

Sub FormClose
  SDB.MessageBox "Got OnShutdown", mtInformation, Array(mbOk)
End Sub

What would be a good thing to put in that sub, once I get the event? I was thinking about

Code: Select all

  SDB.Objects("Pandora Window") = Nothing

but is that just wishful thinking that the right thing will happen?

Thanks in advance for any help.

[Steegy]

Hello

The close event of the form is more than probably OnClose, and not OnShutdown (that one is raised when you shut down the application).

So the line should be:

Code: Select all

Script.RegisterEvent Form, "OnClose", "FormClose"

Yes, when your form closes, you should release the reference:

Code: Select all

Sub FormClose
  SDB.MessageBox "Got OnClose", mtInformation, Array(mbOk)
  SDB.Objects("Pandora Window") = Nothing 
End Sub

BTW: Are you aware that it's now possible to use MediaMonkey's default browser window, referenced by WebControl?
sample code: http://www.mediamonkey.com/forum/viewto ... 9852#39852

Cheers
Steegy

[revbob]

Thanks. OnClose did the trick. I'm getting the event now. Alas, when the window closes, the Pandora applet keeps playing the music and only stops playing when you exit from MM, same as before.

BTW: Are you aware that it's now possible to use MediaMonkey's default browser window, referenced by WebControl?
sample code: http://www.mediamonkey.com/forum/viewto ... 9852#39852

Yeah, but if I use MM and come back to that window, Pandora gets restarted. Curiously, when I display, e.g., a track listing from the library in MM's main pane, the Pandora applet keeps playing the music, just like when I shut down the popup.

When I use another function like this,

Code: Select all

Script.RegisterEvent PandoraNode, "OnNodeFocused", "OpenInDefaultBrowser"

and have a handler like this,

Code: Select all

Sub OpenInDefaultBrowser(PandoraNode)
  Dim WPandoraShell, Command
  Set WPandoraShell = CreateObject("WScript.Shell")
  Command = PandoraNode.CustomData
  Result = WPandoraShell.Run(Command, 0, 0)
End Sub

It works just fine, turning off the music when the window closes.

It sure sounds like the MSIE embedded control isn't telling all its children when it's leaving the building.

Anyhow, I'm beginning to think the error is in the MSIE control and not in my code or in my understanding of OLE (etc.). Does that sound sensible to you?

[Steegy]

most of it...

The way that the WebControl works might seem a bit strange, but it's certainly not an error.
If you understand how these things work, it's quite obvious.
Now I'm trying to explain the difference between the built in WebControl and a custom web page control that you can add yourself:

WebControl: a permanent available web page control that is hidden after the tracklist, and can be made visible through a "OnNodeFocused" event. It doesn't close, it can only be shown and hidden (and it acts as any other web control).

E.g. when the tracklist is shown and you do a WebControl refresh, you can "hear" the page refreshing in the background. That means it's there and it's active (it can be loading/running a page) but just isn't made visible by MediaMonkey.
That means that you could "preload" things in the background, and then show them later by making the WebControl visible.

(To show the WebControl you are accessing, I guess you have to return value 2 from the event handling method.
So, I think the clue is, when OpenInDefaultBrowser (in your code, changed to use the WebControl) returns value 2 (this method is a Function, not a Sub !) MediaMonkey hides the tracklist and shows the WebControl.)


- When you want to close/stop a page in the WebControl, you have to do that by navigating to about:blank or by using the Stop command. The WebControl itself stays available so you can't close it.
By navigating to about:blank or to another page, you are getting rid of the previous page.

- A normal web page control you create and show yourself, can be closed (destroyed, e.g. by closing the form).
When the control is closed, of course the previous page is gone too (automaticly).

Cheers
Steegy

[revbob]

Yeee, hawwww! It works!! Thanks, Steegy.

The whole script is at http://www.mediamonkey.com/forum/viewto ... 3036#43036

The extra bits that make it work are one line toward the end of OpenPopup():

Code: Select all

  ...
  SDB.Objects("Pandora Window") = Form    ' Make the window hang about
  SDB.Objects("Pandora Browser") = BrowserControl.Interf
  Script.RegisterEvent Form, "OnClose", "FormClose"
End Sub

where I park the browser control's interface object. And I come back and get it in FormClose handler (here's the whole thing):

Code: Select all

Sub FormClose(Node)
  SDB.Objects("Pandora Window") = Nothing
  SDB.Objects("Pandora Browser").Navigate "about:blank"
  SDB.Objects("Pandora Browser") = Nothing
End Sub

I've got some qualms about sending an event to an object, particularly an object as complex as a browser control, and then immediately setting the handle to null, for fear the object will ask about its parent, but it doesn't seem to do anything too horrible.

Well, tell a lie, you've got to click something else (pretty much anything) before you click the Pandora node again, but I think that's because OnNodeFocused is an edge triggered event, and it still hasn't left the last state. Verdad?

Anyhow, it seems to be non-evil, and anybody who'd like to add Pandora to MM, you can get it at the URL above.

Thanks again, Steegy.