WPF starting up interfaces without freezing the GUI - wpf

Question

I know there is a bunch of threads about initializing stuff in a different thread so you dont need to freeze your UI. But in my case this initialization involves creating a lot of plots (polylines in a canvas) so it seems to need to freeze the UI.
It could be good enough to hide the frame where things are being initialized (I already let a "loading.." message in below) and freeze the UI then (couple of seconds) and then show again the frame.
This is what I have so far. But is not working... it freezes the UI before hiding nothing and it unfreezes after loading the fully initializes frame.
Otherwise the thing works like a charm.
void Historics_showExperimentResults(object sender, EventArgs e)
{
aepPage = new AEPPage();
resultsPage = new AEPResultSet();
// I try to hide the frame. Below there is a "Loading..." nice text.
// not sure if it's the best way but it works if I dont show anything at the end
ParadigmFrame.Dispatcher.Invoke((Action)delegate
{
ParadigmFrame.Content = null;
ParadigmFrame.UpdateLayout();
});
// This is the initialization that needs to have the GUI thread
//because it draw some plots and polylines
aepPage.Dispatcher.Invoke((Action)delegate
{
aepPage.init(resultSet);
});
//Then I want to go and visualize the initialized page with the plots
ParadigmFrame.Dispatcher.Invoke((Action)delegate
{
ParadigmFrame.Navigate(aepPage);
});
}
Any clue??? As I said I tried to put the init in a different thread and add a event when finished, but this threads needs the control over the UI for initializing the polylines in the canvas so .. it doesn't work :(
Thanks in advance !

Answer 1

It looks like Historics_showExperimentResults is already running on UI thread. Try this:
void Historics_showExperimentResults(object sender, EventArgs e)
{
aepPage = new AEPPage();
resultsPage = new AEPResultSet();
new Thread(_ =>
{
// I try to hide the frame. Below there is a "Loading..." nice text.
// not sure if it's the best way but it works if I dont show anything at the end
ParadigmFrame.Dispatcher.Invoke((Action)delegate
{
ParadigmFrame.Content = null;
ParadigmFrame.UpdateLayout();
});
// This is the initialization that needs to have the GUI thread
//because it draw some plots and polylines
aepPage.Dispatcher.Invoke((Action)delegate
{
aepPage.init(resultSet);
});
//Then I want to go and visualize the initialized page with the plots
ParadigmFrame.Dispatcher.Invoke((Action)delegate
{
ParadigmFrame.Navigate(aepPage);
});
}).Start();
}

Answer 2

I won´t mark this as an answer since it is not .. but still is the workaround I´m using right now.
What I did is split the fade out, the init and the fade in into pieces.
I created a storyboard, fade out and attach the next step to the Finished event so, in some kind of pseudocode it would be:
StoryBoard sb = new StoryBoard;
OnClick(object sender blabla)
{
storyBoard.add(fade out animation over ParadigmFrame);
storyBoard.Completed += performInit;
storyBoard.Begin();
}
So this part is executed and the paradigmFrame disappears showing the ¨Loading...¨ message that´s bellow.
Then ..
private blabla performInit()
{
aepPage.Dispatcher.Invoke((Action)delegate
{
aepPage.Finished += initFinished;
aepPage.init(resultSet);
});
}
For sure I created the Finished event in my aepPage class and fired it when the initialization is finished. So during all this process the UI is freeze. The "Loading..." message is visible and it is not awful but the REAL solution should not freeze the UI in here...
And then I show it up
private void initFinished()
{
storyBoard.add(fade in animation over ParadigmFrame);
storyBoard.Completed -= performInit;
storyBoard.Begin();
}
This is my long and ugly workaround ... I´m still open to new solutions !!!
Thanks !