Success: a 7.1 app backed up on a remote server!

I've spent a bit of time now trying to get the upgraded 7.1 version working, however the app crashes on loading the schedule pivot page containing the jumplist.  I decided to try and put a plain list of the items in order to get a functioning 7.1 app - but  found that the crash wasn't caused by the telerik controls at all.

I tried to get the minimal list going with this:

        <controls:Pivot
            x:Name="schedulePivot"
            HeaderTemplate="{StaticResource pivotTitleTemplate}">
            <controls:PivotItem>
                <ListBox
                    ItemsSource="{Binding events}"
                    ItemTemplate="{StaticResource eventTemplate}">
                </ListBox>
            </controls:PivotItem> (line 64)
        </controls:Pivot>

I got this XAML parse error: AG_E_UNKNOWN_ERROR [Line: 64 Position: 34]

        <controls:Pivot
            x:Name="schedulePivot"
            HeaderTemplate="{StaticResource pivotTitleTemplate}">
            <controls:PivotItem>
                <TextBlock Text="hello" />
            </controls:PivotItem> (line 61)
        </controls:Pivot>

Gives me the same error on line 61, so it isn't about the lists at all.

It turns out I got this error as soon as I add any PivotItem to the pivot, even an empty one.

Ok...looked into the exception stack trace and it included this detail:

            at System.Windows.UIElement.UpdateLayout()
            at Microsoft.Phone.Controls.Pivot.OnItemsChanged(NotifyCollectionChangedEventArgs e)
            at System.Windows.Controls.ItemsControl.OnItemCollectionChanged(Object sender, NotifyCollectionChangedEventArgs e)
            at System.Windows.Controls.ItemCollection.NotifyCollectionChanged(NotifyCollectionChangedEventArgs e)
            at System.Windows.Controls.ItemCollection.NotifyCollectionReady()
            at System.Windows.Controls.ItemsControl.NotifyAllItemsAdded(IntPtr nativeItemsControl)
            at MS.Internal.XcpImports.Application_LoadComponentNative(IntPtr pContext, IntPtr pComponent, UInt32 cUriStringLength, String uriString, UInt32 cXamlStrLength, Byte* pXamlStr, UInt32 cAssemblyStrLength, String assemblyStr)
            at MS.Internal.XcpImports.Application_LoadComponent(IManagedPeerBase componentAsDO, String resourceLocator, UnmanagedMemoryStream stream, UInt32 numBytesToRead, String assemblyString)
            at System.Windows.Application.LoadComponent(Object component, Uri resourceLocator)
            at PAX7.View.SchedulePivotView.InitializeComponent()
            at PAX7.View.SchedulePivotView.OnNavigatedTo(NavigationEventArgs e)
            at Microsoft.Phone.Controls.PhoneApplicationPage.InternalOnNavigatedTo(NavigationEventArgs e)

So I thought perhaps the exception was something to do with the pivotitems I was creating not working with the data I'm assigning to it? I removed the PivotItems and set DataTemplates on the Pivot itself, like this:

        <controls:Pivot x:Name="schedulePivot"
                        HeaderTemplate="{StaticResource pivotTitleTemplate}"
                        ItemTemplate="{StaticResource pivotListTemplate}">
                        
        </controls:Pivot>

Referring to existing templates like this:

        <DataTemplate x:Key="pivotListTemplate">
            <ListBox
                ItemsSource="{Binding events}"
                ItemTemplate="{StaticResource eventTemplate}">
            </ListBox>
        </DataTemplate>

Magic! Finally I have a working app built on the 7.1 SDK :) Obviously I committed it straight away. Then I remembered that I hadn't got a backup on a separate machine yet, so I googled remote repository hg nearlyfreespeech, and found this awesome page:

http://your-hg-repository.nfshost.com/

Before sending it up to my new remote repository,  I thought I'd make sure it wasn't including all my generated files. I found a couple relevant Stack Overflow questions  (e.g. http://stackoverflow.com/questions/3426231/mercurial-hgignore-some-questions-on-how-to-ignore-a-single-file) that led me to the help page (http://www.selenic.com/mercurial/hgignore.5.html). Although when I look at 'all files' in the repository it doesn't list the bin/obj directories now, when I ran the clone it still did because it was looking at the history of the repository, which obviously still mentioned them.

Then cloning failed anyway with an 'invalid argument' error. Google told me there was a known issue with clone/push/pull of large filesets on windows? Lame! (http://mercurial.808500.n3.nabble.com/TortoiseHG-Large-File-Commit-only-40Meg-is-size-td2140178.html) 

So I tried creating a bundle of just the latest revision (http://tortoisehg.bitbucket.org/manual/0.9/changelog.html#revision-context-menus) and cloning it, but tortoise just went ahead and tried creating a stupid huge bundle again when I hit clone, instead of pulling from the bundle. So I turned on the server option, but couldn't figure out what the url should be - when I tried hg pull <url listed in serve ui> I got an error that the hostname wasn't recognised.

I uploaded the bundle I'd created through ssh, and tried pulling from it locally (inspired by http://weblogs.java.net/blog/kohsuke/archive/2007/08/mercurial_trans.html) but got an error that the parent wasn't recognised. However import/export also didn't work, saying it couldn't find files to patch. So I created a backup bundle as listed here (http://www.southampton.ac.uk/~fangohr/computing/hg.html#use-mercurial-without-access-to-server-using-bundles) and copied that to the server, pulled from that and finally had a repository. Done!

I think the whole rigmarole indicates that I don't have a strong enough grasp on how hg is supposed to work.  Let's see how it goes when I try and just copy over a changeset...

Source control/backup and testing.

So for most of my projects I have a Mercurial repository for version control (totally saved my ass when I found a bug in the submitted version of Pax while halfway through unsuccessfully updating the code to 7.1), but no backup. I thought about setting up remote repositories (I have hosting with Nearly Free Speech), but I also remembered that GitHub had recently released their Windows client. I was unable to download/install the client over the coffeeshop wifi so had to set that up at home later - now you can see the code at https://github.com/jacalata/FlashCards. If that works nicely I'll put my Pax code up there as well.

I have created a test project for my Pax app in the past, but...a long time in the past. So I found this guide (http://blogs.msdn.com/b/amit_chatterjee/archive/2011/06/26/unit-testing-the-windows-phone-7-applications.aspx) as a reminder, and also found that the dll's I had were all 7.0 projects, so updated them. Added the first couple of unit tests, more to go.  Does feel better knowing I have a test framework though :)

Flashcards app

I recently got the Telerik controls for Windows Phone (free in a deal for MS employees) and plan to use that to improve my Pax app - specifically I need the jumplist to replace the third party implementation I have now, which doesn't work for a 7.1 app. Before going in to replace everything in my Pax app, I thought I'd create a new app to get used to working with them.  

I have vague aspirations of doing a little more concentrated data structures and algorithms revision this year, and working on my french/icelandic, so I thought I could build myself a flashcard app. I used one of the Telerik default app options, which was nice and clean. I found the couple of controls I added quite simple to use: the basic info is all easily available at http://www.telerik.com/products/windows-phone/overview/all-controls.aspx,  but  I'd love that page to contain the dll each control is in, rather than looking through the 6 options. Or ideally to link to a page for each control with the full docs for it (I'm sure I found full docs, but I've forgotten where - I mostly worked by looking controls up in the Object Browser in VS). 

The first version of the app is super basic: one set of cards, can add/delete only, can move through sequentially or randomly. No option to enter the answer to keep yourself honest, no option to edit cards. What took the most time was creating the icon, which is still totally crap - all Paint no talent. Overall it took me two evenings, (probably about 8 hours) to get a working minimal version ready to submit to the app store. I didn't actually write any tests, which is bad. But it was pretty satisfying to get that done.  

I also set up a Trello board for the app (https://trello.com/board/flashcards-app/4ffb6ccacb4f94632522f9970), which I'm finding to be a really easy way to track projects. To keep myself honest, the next two tasks are tests and version control (I can't believe I forgot to do that).

Upgrading to 7.1

I upgraded my app project to 7.1 back in late March, but it didn't go smoothly. 

Immediately after upgrading, I wanted to run the project and make sure upgrading hadn't broken anything. Unfortunately the first thing I got was a cryptic runtime Exception: 'WrappedException' with details 'Unspecified Error', breaking when I initialised a boolean for the first time. I googled the exception and found other people complaining that upgrading their projects gave them these errors as well - http://forums.create.msdn.com/forums/t/88547.aspx - the problem seemed to be running the old version of the Silverlight Toolkit or the CodingForFun toolkit. I have both of these, so time to upgrade them through nuget.

But...it turned out I have the most recent version? Crap. Try rebuilding from clean - didn't help. 

I searched again and found two articles both mentioning this error in relation to template bindings - http://www.wirebear.com/blog/2010/10/21/windows-phone-7-unspecified-error/ and http://www.telerik.com/community/forums/windows-phone/databound-listbox/unspecified-error-on-databoundlistbox-for-mango.aspx  so I guess I went through my project and checked the templates on that page.

1. Commented out both the headertemplate and the jumplist itemtemplate - the app ran fine

2. Put back in just the header template - app ran fine. So I guess it is /sigh/ somewhere within my horrible nested jumplist template.

3. Just for fun, put them all back in - fails! The exception detail:

MS.Internal.WrappedException was unhandled

  Message=Unspecified error

  StackTrace:

       at MS.Internal.XcpImports.CheckHResult(UInt32 hr)

       at MS.Internal.XcpImports.UIElement_UpdateLayout(UIElement element)

       at System.Windows.UIElement.UpdateLayout()

.....

 InnerException:

       Message=Unspecified error

       StackTrace:

            at MS.Internal.XcpImports.CheckHResult(UInt32 hr)

            at MS.Internal.XcpImports.UIElement_Measure_WithDesiredSize(UIElement element, Size availableSize)

            at System.Windows.UIElement.Measure_WithDesiredSize(Size availableSize)

            at System.Windows.Controls.VirtualizingStackPanel.MeasureChild(UIElement child, Size layoutSlotSize)

            at System.Windows.Controls.VirtualizingStackPanel.MeasureOverride(Size constraint)

 

And I've narrowed it down to this template:

  <DataTemplate x:Key="pivotJumplistTemplate">
            <l:JumpList
                ScrollDuration="400"
                ItemsSource="{Binding events}"
                ItemTemplate="{StaticResource eventTemplateByDay}"
                JumpButtonStyle="{StaticResource AccentColoredButtonStyle}">
                <l:JumpList.CategoryProvider>
                    <l:DistinctPropertyValueCategoryProvider PropertyName="StartTime"/>
                </l:JumpList.CategoryProvider>
            </l:JumpList>
        </DataTemplate>

If I replace this one with the non-jumplist, it works.

        <DataTemplate x:Key="pivotListTemplate">
            <ListBox
                ItemsSource="{Binding events}"
                ItemTemplate="{StaticResource eventTemplate}">
            </ListBox>
        </DataTemplate>

Aha - and now adding Jumplist to my search,  I get this article from the guy who wrote the control I'm using - 

http://www.scottlogic.co.uk/blog/colin/2011/01/a-windows-phone-7-jump-list-control/

All the comments say they are seeing this error. Turns out the control is now distributed as part of http://wp7contrib.codeplex.com/, which has been updated for 7.1. Installed the new package with nuget and swapped out my assembly references….and got the same exception.  And so were other people since September - I can't find an indication that he's updated it since then. I left a comment on the post asking if it had been updated. He's responded a couple of times since then saying he is planning to update, but hasn't had time recently.

Fortunately Telerik recently had a special for Microsoft employees, so I got their Windows Phone suite free - I can insert their jumplist instead.

extracting the hardcoded info

PAX East schedule is out! I need to get cracking on this. I also got another response to my app survey today, where the only feature requested is 'update for pax east'. 

So, last week I implemented the ability to download a hardcoded file from my server. Now I need to adapt that so that I can download whatever files are available, and that I only do this if they are updated from my version.  I want to add this option in an app bar, but I need the collapsed app bar which is only available in mango, and I'm hoping to get one last usable version for pax east out in pre-mango format. So I've added this button in the about page (terrible design, I know). I might also want to add a little notification to the front menu letting the user know if a new version is available?

I should add a 'what's new' popup on first run, like 4th and Mayor.

I wired up a button in the about screen to look for a new schedule on my server, and put a really lame 'version info' file on the server, looks like this

3.1.2012
"East/2012"

So this is - date = last time the server schedule was updated, and location= folder location to look in on the server. In that folder will be a zip file of all the xml files. Each zip needs to be a complete set - I'm not going to try and manage just sending the new events or anything like that. (I'm mostly being inspired here by this article on downloading and reading from a zip - http://www.galasoft.ch/mydotnet/articles/article-2008032301.html) 

I actually format the event schedule  into xml by hand. I copy the plain text from the official website, then

1. Remove special characters - /&" are the main ones. Also odd quote chars like ’ and — and …
2. Manually insert an 'Event' heading for each event
3. arbitrarily decide on the 'type' of the event, basically I put as 'show' anything that doesn't sound like it'll have audience participation/questions. 

Etc etc

I've hardcoded lots of things that need changing. I haven't gotten a full plan for how to best handle this instead.

1. Panorama title says' PAX Prime 2011' - updated

2. Maps are all of Seattle - I have the bcec and boston maps, but will the pax specific ones change? I should probably wait here...nah, I'll almost definitely need to send out another update later. For now let's put in last year's maps.

3. Useful links are seattle based - updated

public get, private set, public crash?

Goodness,  I seem to have found the weirdest bug. I decided to pull all the event headings into the Schedule class ("Manticore" etc) as a precursor to loading these dynamically from a settings file.  I set up the lists like this:

        public List<string> eventDays
        {
            get { return eventDays; }
            private set { }
        }

However, all of a sudden I found that the app would completely and silently crash, not even throwing an exception for me, when it tried to access any of these list variables - even from within the same class. I removed the get/set so they were just public variables, and the app worked fine again. Then I put back this get/set code, and the app crash reliably reproduced, and then visual studio itself crashed.

    public Schedule()
        {
            ObservableCollection<Event> events = new ObservableCollection<Event>();
            Events = events;
            eventDays = new List<string>();
        }

        private void readSchemaFile()
        {
            if (eventLocations == null)
            {
                eventLocations = new List<String>();
            }

   //populate list

      }


edit: the next day, when it was not 2am, someone pointed out to me that I had obviously put a recursive get on eventDays, so it was crashing with a stack overflow. Way to go, me. 

xaml fiddling

Took a 2 day course at work that gave me a good overview of the changes available in mango, but was overall aimed at a new developer and probably not worth my entire two days. I did spend the time working on the app and updated the search to look and act like marketplace search on the device

• Got rid of the separate search.xaml so that now it is presented in the schedulepivotview.xaml like any other view of events
• Had to add a bunch of items to this (search header, search textbox, text to show if a view is empty) and found that if I put it all in a stackpanel, the list of events doesn't scroll (documented online in a couple of places - the list needs to be inside something with a set size, when it's in a stackpanel it thinks it has unlimited viewspace and so doesn’t need to scroll). However if I just put all the items in the top grid and hid the non-relevant ones, then the touch didn't seem to work on the pivot, presumably because other items were 'in the same place'. I worked around this by putting all the extra controls in a stackpanel that was collapsed by default, like this
• <Grid>
• <StackPanel>
• <textblock search header>
• <textbox search entry>
• <Pivot>
• <StackPanel>
• <textblock empty search text>
• <textblock empty 'my schedule' text>

• As a bonus, this made it easy to also implement a notice when the user enters my schedule and has not yet added any items to it.

Also added an inline star to all items that are in your schedule, so you can tell without clicking on details whether you've already added this one.