Develop Reference

Windows Phone 8.1 check if password set else load new page

I Have a very similar situation to this guys question in that I have a Login Page which is my MainPage.xaml file but I have another page called SetPassword.xaml that I want to load if a user has not set a password yet. Essentially this is the first time that the App loads after it has been installed.
I've spent hours on SO trying various different solutions (including the one I linked to) but I'm just not getting anywhere and it seems that many of the solutions are either for WP7 or WP8 and nothing similar has been solved for the new WP8.1.
This is the basic check, using Windows.Storage that I'm doing to see if a password has been set or not.
Windows.Storage.ApplicationDataContainer localSettings = Windows.Storage.ApplicationData.Current.LocalSettings;
Windows.Storage.StorageFolder localFolder = Windows.Storage.ApplicationData.Current.LocalFolder;
if (localSettings.Values["myPassword"] == null)
{
Debug.WriteLine("Password not set");
this.Frame.Navigate(typeof(SetPassword));
}
else
{
Debug.WriteLine("Password is set, continuing as normal");
}
If I add this to public MainPage() class I have no problem in the app returning "Password is not set" in the debug messages however the this.frame.Navigate(typeof(SetPassword)) navigation never loads the SetPassword view.
I have also tried this method in the OnNavigatedTo with exactly the same results.
In my App.xaml file I've also tried a number of different methods, again, with the same results. I can get the debug message but not the navigation I'm looking for. I looked at implementing a method on Application_Launching over here as well as implementing conditional navigation on RootFrame.Navigating+= RootFrameOnNavigating; over here but clearly I am missing something.
Hopefully you smarter people can help me get my navigation working based on a conditional value?

The solution was simple. To do the navigation I could have done it in either App or MainPage as per my question but the reason the navigation wasn't working was because I was trying to navigate to SetPassword.xaml which was a <ContentDialog> instead of a <Page>.
I feel embarrassed actually that I didn't even check that but hopefully if this happens to someone else they can check that they're actually trying to navigate to a Page and not any other type of element. How sadly foolish of me!
EDIT:
Here's what my OnLaunched in the App.xaml file looks like where I can now do my check and redirect to a different page based on the value being set.
protected override void OnLaunched(LaunchActivatedEventArgs e)
{
Frame rootFrame = Window.Current.Content as Frame;
if (rootFrame == null)
{
rootFrame = new Frame();
rootFrame.CacheSize = 1;
Window.Current.Content = rootFrame;
// The following checks to see if the value of the password is set and if it is not it redirects to the save password page - else it loads the main page.
Windows.Storage.ApplicationDataContainer localSettings = Windows.Storage.ApplicationData.Current.LocalSettings;
Windows.Storage.StorageFolder localFolder = Windows.Storage.ApplicationData.Current.LocalFolder;
if (localSettings.Values["myPassword"] == null)
{
rootFrame.Navigate(typeof(SetPassword));
}
else
{
rootFrame.Navigate(typeof(MainPage));
}
}
if (rootFrame.Content == null)
{
if (rootFrame.ContentTransitions != null)
{
this.transitions = new TransitionCollection();
foreach (var c in rootFrame.ContentTransitions)
{
this.transitions.Add(c);
}
}
rootFrame.ContentTransitions = null;
rootFrame.Navigated += this.RootFrame_FirstNavigated;
if (!rootFrame.Navigate(typeof(MainPage), e.Arguments))
{
throw new Exception("Failed to create initial page");
}
}
Window.Current.Activate();
}

How to navigate to a new page from within a OnFrameNavigated handler

I am porting a Windows Phone 8 app to Windows Store 8.1 and I am having some trouble with navigating to a new page when Frame.Navigate(...) is called from within a OnFrameNavigated handler.
The long story:
The App manages different "Media" objects like Books or Films. To edit the properties (title, author, etc.) of such an element the WP uses a custom "MediaEditor" control that was inspired by the DatePicker from the WP ToolKit:
Instead of manually navigating to an Editor/Picker page the Editor/Picker is capsuled in its own class. This class hooks up to the ApplicationFrame and handles Navigation to the Editor/Picker page on its own. When the ApplicationFrame navigates back to the page/content that was visible before showing the Editor/Picker the result can be processed, e.g. fire an event with the picked date.
There is one difference in my MediaEditor compared to the DatePicker:
If the MediaItem that is currently edited is related to another MediaItem (e.g. Movie A is the film version of Book A) the editing of this item can directly been started from within the MediaEditor:
call mediaEditor.Edit(MovieA) --> MediaEditor for MovieA is displayed
Select to Edit BookA from within MediaEditor --> MediaEditor for MovieA is closed and MediaEditor for BoolB is displayed
This is done by calling Edit(BookA) from within OnFrameNavigated. Thus the complete Navigation is:
call mediaEditor.Edit(MovieA) --> Frame.Navigate(typeof(MediaEditorPage), MovieA)
Select to Edit BookA --> Frame.GoBack()
Detect that BookA should be edited in OnFrameNavigated --> Frame.Navigate(typeof(MediaEditorPage), BookA)
While this works on Windows Phone this does not work on Win 8.1. Frame.Navigate(typeof(MediaEditorPage), BookA) is simply ignored. There is no OnNavigationFailed, no console output, nothing. The App navigates back to the first page (the one that original called mediaEditor.Edit(MovieA)) and nothing else happens.
What exactly is the problem here?
MediaEditor mediaEditor = new MediaEditor();
mediaEditor.Edit(bookItem);
public class MediaEditor {
private Frame applicationFrame;
private object frameContentWhenOpened;
public void Edit(MediaItem item) {
applicationFrame = Window.Current.Content as Frame;
if (applicationFrame != null) {
frameContentWhenOpened = applicationFrame.Content;
applicationFrame.Navigated += OnFrameNavigated;
applicationFrame.NavigationFailed += OnNavigationFailed;
applicationFrame.Navigate(typeof(MediaEditorPage), item);
}
}
void OnNavigationFailed(object sender, NavigationFailedEventArgs e) {
System.Diagnostics.Debug.WriteLine(e);
}
MediaEditorPage editorPage;
void OnFrameNavigated(object sender, NavigationFailedEventArgs e) {
if (e.Content == frameContentWhenOpened) {
applicationFrame.Navigated -= OnFrameNavigated;
applicationFrame.NavigationFailed -= OnNavigationFailed;
applicationFrame = null;
frameContentWhenOpened = null;
if (editorPage != null) {
if (editorPage.EditOtherItem)
// Directly start editing another Item
Edit(editorPage.OtherItem);
else
// Finish editing, fire Events, etc
}
} else {
editorPage = e.Content as MediaEditorPage ;
}
}
}

WP8: Fast app resume + secondary tile + MainPage = 2 instances

I'm having the same problem posed here:
http://social.msdn.microsoft.com/Forums/wpapps/en-us/af8615e7-8e90-4069-aa4d-3c4a84a6a3d0/windows-phone-8-fast-app-resume-with-deeplinks?forum=wpdevelop
I'm no C# or WP expert, so please bear with me.
I have secondary tiles which link to "/MainPage.xaml?id=XX".
I have fast app resume enabled. (ActivationPolicy="Resume" in the app manifest)
I only have one page in my app: MainPage.xaml.
Problem: When I resume the app using a secondary tile ("/MainPage.xaml?id=XX"), I get a brief view of the previous instance (that would have resumed) and then the MainPage initializes again, creating a new instance. In effect, the app is loading from scratch after giving me a peek of what was previously open.
That is obviously undesired behavior. I want to use the existing instance to perform my task.
Attempt 1:
Use e.Cancel = true; to cancel the navigation to the MainPage.xaml:
(using the App.xaml.cs code from the official Fast App Resume sample to identify how the app was launched)
...
else if (e.NavigationMode == NavigationMode.New && wasRelaunched)
{
// This block will run if the previous navigation was a relaunch
wasRelaunched = false;
if (e.Uri.ToString().Contains("="))
{
// This block will run if the launch Uri contains "=" (ex: "id=XX") which
// was specified when the secondary tile was created in MainPage.xaml.cs
sessionType = SessionType.DeepLink;
e.Cancel = true; // <======================== Here
// The app was relaunched via a Deep Link.
// The page stack will be cleared.
}
}
...
Problem: In doing so, my OnNavigatedTo event handlers never fire, so my query string is never parsed.
protected override void OnNavigatedTo(System.Windows.Navigation.NavigationEventArgs e)
{
String navId;
if (e.NavigationMode != System.Windows.Navigation.NavigationMode.Back)
{
if (NavigationContext.QueryString.TryGetValue("id", out navId))
{
MessageBox.Show(navId.ToString()); // Not reached
}
}
...
Attempt 2:
Use e.Cancel = true; to cancel the navigation to the MainPage.xaml, AND pass the Uri to a method in MainPage:
// App.xaml.cs
...
else if (e.NavigationMode == NavigationMode.New && wasRelaunched)
{
// This block will run if the previous navigation was a relaunch
wasRelaunched = false;
if (e.Uri.ToString().Contains("="))
{
// This block will run if the launch Uri contains "=" (ex: "id=XX") which
// was specified when the secondary tile was created in MainPage.xaml.cs
sessionType = SessionType.DeepLink;
e.Cancel = true;
MainPage.GoToDeepLink(e.Uri); // <======================== Here
// The app was relaunched via a Deep Link.
// The page stack will be cleared.
}
}
...
// MainPage.xaml.cs
public static void GoToDeepLink(Uri uri) // <======================== Here
{
// Convert the uri into a list and navigate to it.
string path = uri.ToString();
string id = path.Substring(path.LastIndexOf('=') + 1);
MyList list = App.ViewModel.ListFromId(Convert.ToInt32(id));
pivotLists.SelectedItem = list;
}
Problem: I get an error that pivotLists is non-static and thus requires an object reference. I think that in order to get this to work I'd need to create a new instance of MainPage (MainPage newMainPage = new MainPage();) and call newMainPage.pivotLists.SelectedItem = list; -- BUT I don't know how to use newMainPage instead of the existing one/replace it... or if that's something I want/won't cause further problems/complications.
I don't know what the solution is to this problem, and I may be going in the completely wrong direction. Please keep all suggestions in simple terms with code examples if you can, I'm still learning.
Thanks for any help.

It seems that when you reopen your App from secondary tile, then it's reactivated and new instance of MainPage is created (even if there is one from previous run). If I understood you correctly, I've managed to do such a thing:
In app.xaml.cs:
I've added a variable which indicates if I should return to previous MainPage after Navigating from secondary tile - it needs to be static as I want to have access to it from MainPage
public static bool returnPage = false;
In RootFrame_Navigating I'm setting this variable to true in:
// ...
else if (e.NavigationMode == NavigationMode.New && wasRelaunched)
{
// This block will run if the previous navigation was a relaunch
wasRelaunched = false;
returnPage = true;
// ...
In ClearBackStackAfterReset - prevent from deleting the old Page, when returning:
// ...
if (e.NavigationMode != NavigationMode.New || returnPage)
return;
// ...
In MainPage.cs:
I've changed a little constructor, as I don't want to see a blink of a new Page:
public MainPage()
{
if (!App.returnPage)
InitializeComponent();
}
In MainPage I've also variable which is passed from secondary tile - it's also static, as I need only one instance of it:
private static string navId = "";
And the core of the trick - OnNavigatedTo:
protected override void OnNavigatedTo(NavigationEventArgs e)
{
if (App.returnPage)
{
App.returnPage = false;
NavigationContext.QueryString.TryGetValue("id", out navId);
NavigationService.GoBack();
}
else if (e.NavigationMode != NavigationMode.Reset)
{
// normal navigation
}
}
It works like this:
when you launch normally your App, returnPage is false, everything goes normal
when you activate it from secondary tile few things happen:
1. first goes navigation to your previous page with NavigationMode.Reset - we are not interested in it, so I switched it off - nothing should happen
2. then program tries to create new instance of MainPage, but returnPage is true, and because of the if statement, InitializeComponent won't run. Just after this, in OnNavigatedTo, program saves passed querystring and Navigates Back to previous instance of MainPage - from previous run
3. at last we are navigating to right MainPage with NavigationMode.Back and we have our querystring saved in static variable.
You must be aware of two things: first - probably it can be little rebuild (I'm not sure if wasRelaunched is needed and so on) - you need to debug it and see of what you can get rid off. Second - you will probably need to test your App with Tombstone case.
Hope this helps.

save and load Listbox Items locally and pass them to other pages

I am currently working on Windows Store App in c#.
Now,
I am having a list box 'Listbox1' which gets its items on a button click event from a text box 'tasks', and have selected Items delete property on other button click event.
private void add_Click(object sender, RoutedEventArgs e)
{
string t;
t = tasks.Text;
if (t != "")
{
Listbox1.Items.Add(t);
}
else
{
var a = new MessageDialog("Please Enter the Task First");
a.Commands.Add(new UICommand("Ok"));
a.ShowAsync();
}
tasks.Text = "";
}
private void del_Click(object sender, RoutedEventArgs e)
{
for (int p = 0; p < Listbox1.SelectedItems.Count; p++)
{
Listbox1.Items.Remove(Listbox1.SelectedItems[p].ToString());
p--;
}
}
Now I want to save this list into local application storage, after user complete the changes (on a button click event perhaps).
And also to send all Listbox Items to another page(s).
I am not much a coder, I design things.
Please guide me by sample or reference.
Thank you in advance :)

If you have already stored the data to local storage, you could just read it in the OnNavigatedTo override of the other page. Otherwise, use the navigation parameter: http://social.msdn.microsoft.com/Forums/windowsapps/en-US/8cb42356-82bc-4d77-9bbc-ae186990cfd5/passing-parameters-during-navigation-in-windows-8
Edit: I am not sure whether you also need some information about local storage. This is easy: Windows.Storage.ApplicationData.Current.LocalSettings has a property called Values, which is a Dictionary you can write your settings to. Have a look at http://msdn.microsoft.com/en-us/library/windows/apps/hh700361.aspx
Edit: Try something like this code to store your list.
// Try to get the old stuff from local storage.
object oldData = null;
ApplicationDataContainer settings = ApplicationData.Current.LocalSettings;
bool isFound = settings.Values.TryGetValue("List", out oldData);
// Save a list to local storage. (You cannot store the list directly, because it is not
// serialisable, so we use the detours via an array.)
List<string> newData = new List<string>(new string[] { "test", "blah", "blubb" });
settings.Values["List"] = newData.ToArray();
// Test whether the saved list contains the expected data.
Debug.Assert(!isFound || Enumerable.SequenceEqual((string[]) oldData, newData));
Note, this is only demo code for testing - it does not make real sense...
Edit: One advice: Do not persist the list in your click handlers as this will become extremely slow as the list grows. I would load and save the list in the Navigation handlers, i.e. add something like
protected override void OnNavigatedTo(NavigationEventArgs e) {
base.OnNavigatedTo(e);
if (this.ListBox1.ItemsSource == null) {
object list;
if (ApplicationData.Current.LocalSettings.Values.TryGetValue("List", out list)) {
this.ListBox1.ItemsSource = new List<string>((string[]) list);
} else {
this.ListBox1.ItemsSource = new List<string>();
}
}
}
protected override void OnNavigatedFrom(NavigationEventArgs e) {
if (this.ListBox1.ItemsSource != null) {
ApplicationData.Current.LocalSettings.Values["List"] = this.ListBox1.ItemsSource.ToArray();
}
base.OnNavigatedFrom(e);
}

Here is very nice simple example on SQLite DataBase Use in winRT app Development. Look at it and you will know how you can store your Data on the Local Machine. I learned Basic code from this example.
http://blogs.msdn.com/b/robertgreen/archive/2012/11/13/using-sqlite-in-windows-store-apps.aspx
Now, for ease of navigation let me suggest you a flow for this portion of your app.
take one ObservableCollection<> of string and store values of
that textBox into this ObservationCollection with onClick() and then
refer that ObservableCollection<String> to the ItemsList of the
listBox.
now at the time you need to send your Data to the next page, make one parameterised constructor of next page and pass that ObservableCollection<String> as it's parameter.
Now you can access those Data in your constructor and can use as however you want.
Hope this will help..

HelpFile contents are not opened

I have an applications that install two other application which has a "Help" option. Each of these application has a common help file but the contents should be displayed based on the index selected for the application in the "Table of Contents". If i open one application, the help of that particular application should be displayed.
My code looks like this for Appl1.
private void Help_Click(Core.CommandBarButton Ctrl, ref bool CancelDefault)
{
if (System.IO.File.Exists(new PlugInConstants().HELP_FILE_Path))
{
System.Windows.Forms.Help.ShowHelp(new System.Windows.Forms.Control(),
new PlugInConstants().HELP_FILE_Path,
System.Windows.Forms.HelpNavigator.TableOfContents, "Appl1");
}
else
{
System.Windows.Forms.MessageBox.Show(m_objLanguage.ERR_HELP_NOT_FOUND.Replace
("%1", m_objGlobalConfig.HelpFilename));
}
CancelDefault = false;
}
and looks like this for Appl2
private void HelpToolStripMenuItem_Click(object sender, EventArgs e)
{
helpToolStripMenuItem.Enabled = false;
string helpFilePath;
helpFilePath = new TrayConstants().HELP_FILE_Path;
if (System.IO.File.Exists(helpFilePath))
{
System.Windows.Forms.Help.ShowHelp(new System.Windows.Forms.Control(),
helpFilePath, System.Windows.Forms.HelpNavigator.TableOfContents, "Appl2") ;
}
else
{
if (m_helpPage == null)
m_helpPage = new HelpPage();
m_helpPage.ShowDialog();
}
helpToolStripMenuItem.Enabled = true;
}
from this i can only see the Content page of common helpfile, but not the particular application help that is selected.
Now i did run Appl1 but still i can see the main MyAppbut not Appl1that is automatically selected and the contents that is displayed to right.
I am using VS 2010,C#, win forms
thanks in advance

I believe that your issue is that you are accessing the wrong value in the HelpNavigator enum. Looks like it should be Topic, not TableOfContents.
System.Windows.Forms.Help.ShowHelp(new System.Windows.Forms.Control(),
helpFilePath, System.Windows.Forms.HelpNavigator.Topic, "Appl2") ;
http://msdn.microsoft.com/en-us/library/system.windows.forms.helpnavigator.aspx