Detecting when a template was loaded in wpf - controltemplate

I am working with an attached behavior for logging user actions on a ScrollBar.
my code:
class ScrollBarLogBehavior : Behavior<ScrollBar>
{
protected override void OnAttached()
{
base.OnAttached();
AssociatedObject.Loaded += new RoutedEventHandler(AssociatedObject_Loaded);
}
void AssociatedObject_Loaded(object sender, RoutedEventArgs e)
{
...
var track = (Track)AssociatedObject.Template.FindName("PART_Track", AssociatedObject);
// ** HERE is the problem: track is null ! **
...
}
How can I detect that the template has loaded and I can find the Track?
(when I call AssociatedObject.Template.LoadContent() the result containt the requested Track, so it i a matter of timing and not a matter of wrong template or naming)

Override the method OnApplyTemplate
public override void OnApplyTemplate()
{
base.OnApplyTemplate();
var textBox = Template.FindName("PART_Textbox", this) as TextBox;
}

I did not find any good way to detect when the template was loaded. However, I did find a way to find the Track:
in OnAttached() - register to Scroll event fo the ScrollBar (this can only happen after the entire template is loaded, of course):
protected override void OnAttached()
{
base.OnAttached();
_scrollHandler = new ScrollEventHandler(AssociatedObject_Scroll);
AssociatedObject.AddHandler(ScrollBar.ScrollEvent, _scrollHandler, true);
}
When handling the Scroll event, remove registration and find the Thumb:
void AssociatedObject_Scroll(object sender, ScrollEventArgs e)
{
var track = (Track)AssociatedObject.Template.FindName("PART_Track", Associated
if (track == null)
return;
AssociatedObject.RemoveHandler(ScrollBar.ScrollEvent, _scrollHandler);
// do my work with Track
...
}

If I understand correctly, you wish to create an attached behavior that will reference a template part after the ScrollBar has been loaded.
The following should work:
internal static class ScrollBarLogBehavior
{
public static readonly DependencyProperty LogUserActionProperty = DependencyProperty.RegisterAttached(
"LogUserAction",
typeof(bool),
typeof(ScrollBarLogBehavior),
new UIPropertyMetadata(default(bool), LogUserActionChanged));
public static bool GetLogUserAction(DependencyObject obj)
{
return (bool)obj.GetValue(LogUserActionProperty);
}
public static void SetLogUserAction(DependencyObject obj, bool value)
{
obj.SetValue(LogUserActionProperty, value);
}
public static void LogUserActionChanged(DependencyObject s, DependencyPropertyChangedEventArgs e)
{
if (s is ScrollBar scrollBar)
{
scrollBar.Loaded += OnScrollBarLoaded;
}
}
private static void OnScrollBarLoaded(object sender, RoutedEventArgs e)
{
if (sender is ScrollBar scrollBar)
{
if (scrollBar.Template != null)
{
// I'm not sure, but the `name` in the following method call might be case sensitive.
if (scrollBar.Template.FindName("PART_Track", scrollBar) is Track track)
{
// do work with `track` here
}
}
}
}
}
where you would "attach" the behavior in your XAML with:
<ScrollBar guiControls:ScrollBarLogBehavior.LogUserAction="True">
<!-- more here -->
</ScrollBar>
BE ADVISED: this implementation completely ignores the bool value that is being set for LogUserAction

Related

Need to print UWP MapControl with route results

I have a MapControl working just creating my route. Now, I just need to figure out a way to print it out. Using the UWP printing sample, I get a black box where the control should be. The map and route are being built, just not rendered correctly in the print preview. I thought I saw a MapControl.Print... but I think that was in the Bing.Maps stuff. Any pointers would be appreciated. Thanks.
Using the UWP printing sample, I get a black box where the control should be.
It seems the MapControl can not be printed.
As a workround, we can use RenderTargetBitmap to get the image from the MapControl. That we can print the image.
Using a RenderTargetBitmap, you can accomplish scenarios such as applying image effects to a visual that originally came from a XAML UI composition, generating thumbnail images of child pages for a navigation system, or enabling the user to save parts of the UI as an image source and then share that image with other apps.
Because RenderTargetBitmap is a subclass of ImageSource, it can be used as the image source for Image elements or an ImageBrush brush.
For more info,see RenderTargetBitmap.
For example:
RenderTargetBitmap renderTargetBitmap = new RenderTargetBitmap();
await renderTargetBitmap.RenderAsync(MyMap);
MyImage.Source = renderTargetBitmap;
The printing code:
public sealed partial class MainPage : Page
{
private PrintManager printmgr = PrintManager.GetForCurrentView();
private PrintDocument printDoc = null;
private PrintTask task = null;
public MainPage()
{
this.InitializeComponent();
printmgr.PrintTaskRequested += Printmgr_PrintTaskRequested;
}
private void Printmgr_PrintTaskRequested(PrintManager sender, PrintTaskRequestedEventArgs args)
{
var deferral = args.Request.GetDeferral();
task = args.Request.CreatePrintTask("Print", OnPrintTaskSourceRequrested);
task.Completed += PrintTask_Completed;
deferral.Complete();
}
private void PrintTask_Completed(PrintTask sender, PrintTaskCompletedEventArgs args)
{
//the PrintTask is completed
}
private async void OnPrintTaskSourceRequrested(PrintTaskSourceRequestedArgs args)
{
var def = args.GetDeferral();
await Dispatcher.RunAsync(Windows.UI.Core.CoreDispatcherPriority.Normal,
() =>
{
args.SetSource(printDoc?.DocumentSource);
});
def.Complete();
}
private async void appbar_Printer_Click(object sender, RoutedEventArgs e)
{
if (printDoc != null)
{
printDoc.GetPreviewPage -= OnGetPreviewPage;
printDoc.Paginate -= PrintDic_Paginate;
printDoc.AddPages -= PrintDic_AddPages;
}
this.printDoc = new PrintDocument();
printDoc.GetPreviewPage += OnGetPreviewPage;
printDoc.Paginate += PrintDic_Paginate;
printDoc.AddPages += PrintDic_AddPages;
bool showPrint = await PrintManager.ShowPrintUIAsync();
}
private void PrintDic_AddPages(object sender, AddPagesEventArgs e)
{
printDoc.AddPage(this);
printDoc.AddPagesComplete();
}
private void PrintDic_Paginate(object sender, PaginateEventArgs e)
{
PrintTaskOptions opt = task.Options;
printDoc.SetPreviewPageCount(1, PreviewPageCountType.Final);
}
private void OnGetPreviewPage(object sender, GetPreviewPageEventArgs e)
{
printDoc.SetPreviewPage(e.PageNumber, this);
}
}

Umbraco unpublish Event not working for the current node

I am developing Umbraco 7 MVC application and my requirement is to add Item inside Umbraco. Item name should be unique. For that used the below code but I am getting the error "Oops: this document is published but is not in the cache (internal error)"
protected override void ApplicationStarting(UmbracoApplicationBase umbracoApplication,
ApplicationContext applicationContext)
{
ContentService.Publishing += ContentService_Publishing;
}
private void ContentService_Publishing(IPublishingStrategy sender, PublishEventArgs<IContent> e)
{
try
{
if(newsItemExists)
{
e.Cancel = true;
}
}
catch (Exception ex)
{
e.Cancel = true;
Logger.Error(ex.ToString());
}
}
Then I tried adding code to unpublish but its not working i.e the node is getting published. Below is my code
private void ContentService_Publishing(IPublishingStrategy sender, PublishEventArgs<IContent> e)
{
try
{
int itemId=1234; //CurrentPublishedNodeId
if(newsItemExists)
{
IContent content = ContentService.GetById(itemId);
ContentService.UnPublish(content);
library.UpdateDocumentCache(item.Id);
}
}
catch (Exception ex)
{
e.Cancel = true;
Logger.Error(ex.ToString());
}
}
But with the above code, if you give the CurrentPublishedNodeId=2345 //someOthernodeId its unpublished correctly.
Can you please help me on this issue.
You don't have to do this, Umbraco will automatically append (1) to the name if the item already exists (so it IS unique).
If you don't want this behavior you can check in the following way:
protected override void ApplicationStarting(UmbracoApplicationBase umbracoApplication, ApplicationContext applicationContext)
{
ContentService.Publishing += ContentService_Publishing;
}
private void ContentService_Publishing(Umbraco.Core.Publishing.IPublishingStrategy sender, PublishEventArgs<IContent> e)
{
var contentService = UmbracoContext.Current.Application.Services.ContentService;
// It's posible to batch publish items, so go through all items
// even though there might only be one in the list of PublishedEntities
foreach (var item in e.PublishedEntities)
{
var currentPage = contentService.GetById(item.Id);
// Go to the current page's parent and loop through all of it's children
// That way you can determine if any page that is on the same level as the
// page you're trying to publish has the same name
foreach (var contentItem in currentPage.Parent().Children())
{
if (string.Equals(contentItem.Name.Trim(), currentPage.Name.Trim(), StringComparison.InvariantCultureIgnoreCase))
e.Cancel = true;
}
}
}
I think your problem might be that you're not looping through all PublishedEntities but using some other way to determine the current page Id.
Note: Please please please do not use the library.UpdateDocumentCache this, there's absolutely no need, ContentService.UnPublish will take care of the cache state.

MvvmCross ViewModel transition from the left

I am developing an app for iOS using MvvmCross. On one of my Views I have some basic report data that is displayed in a tableview.
When the table row is touched a new view containing a detail report is displayed by making the call to ShowViewModel passing some parameters in a Dictionary. This works fine.
When the user swipes left or right the app needs to show the detail report for the next or previous item in the original list. I am doing this by updating some parameters and calling ShowViewModel again. The logic behind this is all working fine.
My problem; ShowViewModel animates the new view coming in from the right. This is perfect when the user has swiped left. However when swiping right it seems counter intuitive. How can I make ShowViewModel animate or transition in from the left side?
if you look to the MvvmCross source code here you see how the default behavior is showing the ViewControllers
You need to change that by doing something like the following:
How to change the Push and Pop animations in a navigation based app
for that, one idea is to have a custom view presenter and catch navigation to that particular view-model (override Show(IMvxTouchView view) )
or, maybe derive from UINavigationController, set it to MvvmCross to use it (look to the MvxSetup), and on some events change transition to that particular view
similar to this question
How to specify view transitions on iPhone
This is the solution I was able to come up with following the helpful pointers in the answer from Andrei N. In the end I opted for a TransitionFlipFromRight and TransitionFlipFromLeft when scrolling between detail reports. Hopefully it is useful to somebody else.
I already had a presenter class that was inherited from MvxModalSupportTouchViewPresenter
public class BedfordViewPresenter : MvxModalSupportTouchViewPresenter
Within this class I added a property of MvxPresentationHint.
private MvxPresentationHint _presentationHint;
In the override of method ChangePresentation the above property is used to store the passed in parameter
public override void ChangePresentation (MvxPresentationHint hint)
{
_presentationHint = hint;
base.ChangePresentation (hint);
}
Two new MvxPresentationHint class were declared (see later)
In the presenter class the Show method was overridden
public override void Show(IMvxTouchView view)
{
if (_presentationHint is FlipFromRightPresentationHint) {
var viewController = view as UIViewController;
MasterNavigationController.PushControllerWithTransition (viewController, UIViewAnimationOptions.TransitionFlipFromRight);
}
else
if (_presentationHint is FlipFromLeftPresentationHint) {
var viewController = view as UIViewController;
MasterNavigationController.PushControllerWithTransition (viewController, UIViewAnimationOptions.TransitionFlipFromLeft);
}
else {
base.Show (view);
}
_presentationHint = null;
}
A new class that provides extensions to a UINavigationController was created with the method PushControllerWithTransition
public static class UINavigationControllerExtensions
{
public static void PushControllerWithTransition(this UINavigationController
target, UIViewController controllerToPush,
UIViewAnimationOptions transition)
{
UIView.Transition(target.View, 0.75d, transition, delegate() {
target.PushViewController(controllerToPush, false);
}, null);
}
}
All that needs to be defined now are the two new MvxPresentationHint class derivations. These belong in your Core class library project rather than the iOS application project.
public class FlipFromLeftPresentationHint : MvxPresentationHint
{
public FlipFromLeftPresentationHint ()
{
}
}
and
public class FlipFromRightPresentationHint: MvxPresentationHint
{
public FlipFromRightPresentationHint ()
{
}
}
I hope this is a help to someone else trying to do something similar
Share my solution for android:
On view:
public override View OnCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState)
{
var view = base.OnCreateView(inflater, container, savedInstanceState);
var layout = view.FindViewById<LinearLayout>(Resource.Id.swippeable);
var swipeListener = new SwipeListener(this.Activity);
swipeListener.OnSwipeLeft += (sender, e) => this.ViewModel.LeftCommand?.Execute(); //Here use command into view model
swipeListener.OnSwipeRight += (sender, e) => this.ViewModel.RightCommand?.Execute();
layout.SetOnTouchListener(swipeListener);
return view;
}
Gesture listener:
public class SwipeListener : SimpleOnGestureListener, View.IOnTouchListener
{
private const int SWIPE_THRESHOLD = 100;
private const int SWIPE_VELOCITY_THRESHOLD = 100;
private readonly GestureDetector gestureDetector;
public SwipeListener(Context ctx)
{
this.gestureDetector = new GestureDetector(ctx, this);
}
public Boolean OnTouch(View v, MotionEvent e)
{
return this.gestureDetector.OnTouchEvent(e);
}
public event EventHandler OnSwipeRight;
public event EventHandler OnSwipeLeft;
public event EventHandler OnSwipeTop;
public event EventHandler OnSwipeBottom;
public override Boolean OnDown(MotionEvent e)
{
return true;
}
public override Boolean OnFling(MotionEvent e1, MotionEvent e2, float velocityX, float velocityY)
{
Boolean result = false;
float diffY = e2.GetY() - e1.GetY();
float diffX = e2.GetX() - e1.GetX();
if (Math.Abs(diffX) > Math.Abs(diffY))
{
if (Math.Abs(diffX) > SWIPE_THRESHOLD && Math.Abs(velocityX) > SWIPE_VELOCITY_THRESHOLD)
{
if (diffX > 0)
{
SwipeRight();
}
else
{
SwipeLeft();
}
result = true;
}
}
else if (Math.Abs(diffY) > SWIPE_THRESHOLD && Math.Abs(velocityY) > SWIPE_VELOCITY_THRESHOLD)
{
if (diffY > 0)
{
SwipeBottom();
}
else
{
SwipeTop();
}
result = true;
}
return result;
}
public void SwipeRight()
{
this.OnSwipeRight?.Invoke(this, EventArgs.Empty);
}
public void SwipeLeft()
{
this.OnSwipeLeft?.Invoke(this, EventArgs.Empty);
}
public void SwipeTop()
{
this.OnSwipeTop?.Invoke(this, EventArgs.Empty);
}
public void SwipeBottom()
{
this.OnSwipeBottom?.Invoke(this, EventArgs.Empty);
}
}

MVVMCross binding text on Ended event UITextField

I am trying to implement a custom binding on a subclass of UITextField so that the bound value is set when the user is done editing instead of with each keystroke because some interim values are invalid in the viewmodel (for example, while setting 'Age' to '26', a value of '2' is invalid so I'd like to wait to set the value until both digits are there). Something similar to setting UpdateSourceTrigger in xaml. I looked at several examples here:
MvvmCross UITextField custom binding is similar, as is MvvmCross: change update source trigger property of binding on MonoDroid (but for Android). I've also watch N=28 custom binding and looked at the source for MvxUITextFieldTextTargetBinding.
I think I'm close, but my custom binding never gets created and the UITextFields in my app still FireValueChanged with every keystroke.
I created the following Custom Binding:
public class UITextFieldFocusChangedBinding : MvxTargetBinding
{
private bool _subscribed;
private UITextField _view;
public UITextFieldFocusChangedBinding(UITextField target) : base(target)
{
_view = target;
}
public override void SetValue(object value)
{
if (_view == null) return;
_view.Text = (string)value;
}
public override void SubscribeToEvents()
{
var view = _view;
if (view == null)
return;
view.Ended += TextFieldOnEnded;
}
private void TextFieldOnEnded(object sender, EventArgs eventArgs)
{
var view = _view;
if (view == null)
return;
if (!view.IsFirstResponder)
FireValueChanged(view.Text);
_subscribed = true;
}
public override Type TargetType
{
get { return typeof(string); }
}
public override MvxBindingMode DefaultMode
{
get { return MvxBindingMode.TwoWay; }
}
protected override void Dispose(bool isDisposing)
{
if (isDisposing)
{
var view = _view;
if (view != null && _subscribed)
{
view.Ended -= TextFieldOnEnded;
_subscribed = false;
}
}
base.Dispose(isDisposing);
}
}
My setup.cs contains the following:
protected override void FillTargetFactories(IMvxTargetBindingFactoryRegistry registry)
{
base.FillTargetFactories(registry);
registry.RegisterPropertyInfoBindingFactory(typeof(Bindings.UITextFieldFocusChangedBinding),typeof(UITextField), "Text");
}
and in my MvxViewController I have:
var set = this.CreateBindingSet<LifeNeedsView, LifeNeedsViewModel>();
set.Bind(_txtFinMedExpenses).To(vm => vm.FinalMedicalExpenses);
set.Apply();
The bindings work (values are passing correctly) but with every keystroke. Any suggestions on what I might be missing?

Umbraco 6: How to put newly created node on top

In Umbraco 6, when you create a new node, it is put at the bottom.
You have to sort it manually if you want it to be on the top.
How can you make new nodes appear on the top by default?
You could create an event handler that changes the sort order of the nodes when the new node is created. See Application startup events & event registration for more details on implementing an handler of your own.
Rough untested example which I am sure you could make more elegant but should point you in the right direction:
public class YourApplicationEventHandlerClassName : ApplicationEventHandler
{
protected override void ApplicationStarted(UmbracoApplicationBase umbracoApplication, ApplicationContext applicationContext)
{
ContentService.Created += ContentServiceCreated;
}
private void ContentServiceCreated(IContentService sender, NewEventArgs<IContent> e)
{
var cs = ApplicationContext.Current.Services.ContentService;
var content = e.Entity;
var parentNode = content.Parent();
content.SortOrder = parentNode.Children().OrderBy(n => n.SortOrder).First().SortOrder - 1;
cs.Save(content);
}
}
The ContentService.Created event did not work for me. Took some battles, but in v7 of Umbraco, I've used the ContentService.Saved event instead, with some double checking on dirty properties to ensure you don't end up in a saving infinite loop:
private void ContentSaved(IContentService sender, SaveEventArgs<IContent> e)
{
foreach (var content in e.SavedEntities)
{
var dirty = (IRememberBeingDirty)content;
var isNew = dirty.WasPropertyDirty("Id");
if (!isNew) return;
var parentNode = content.Parent();
if (parentNode == null) return;
var last = parentNode.Children().OrderBy(n => n.SortOrder).FirstOrDefault();
if (last != null)
{
content.SortOrder = last.SortOrder - 1;
if (content.Published)
sender.SaveAndPublishWithStatus(content);
else
sender.Save(content);
}
}
}
public class AppStartupHandler : ApplicationEventHandler
{
protected override void ApplicationInitialized(UmbracoApplicationBase umbracoApplication,
ApplicationContext applicationContext)
{
ContentService.Saved += ContentSaved;
}
}

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