When I want to create a new content page in a MAUI project, I have 2 options, ContentPage C#and ContentPage XAML.
Which is the difference between both of them?
There is some cases where is better to use one than the other?
Thanks.
One is a XAML file with a C# code behind. The other is purely a C# class.
One is not inherently "better" than the other. It is purely a matter of preference and coding style.
Related
Can anyone help.
We are working on an app which has a consistent header and footer and therefore ideally we'll use one viewmodel for the "home page" but we want the header and footer to remain.
Before we switched to starting using Prism, this was easy enough to navigate as we could control that in the Pages event and set the page.contentFrame.Navigate method to go where we wanted.
Now we're using the MVVM structure (which is superb and wish I'd done it ages ago) the NavigationService class only navigates the entire page (the VisualStateAware page).
How can I set this up so that when calling the Navigate method on the interface in the viewmodel that only the main content frame is ever navigated? or is there a better approach to this?
Any help would be greatly appreciated.
thank you
The question title seems to, pre-empt the details of the question slightly as a solution. But to share a common view model and visual parts across all pages, within a frame, using the navigation service to navigate between pages here is an overview..
Create a shared ViewModel, say "HeaderViewModel" of type say IHeaderViewModel to be shared between the different pages' view models. Inject this into the constructor of each page's ViewModel.
Then expose this as a property of each page's ViewModel. This property could also be called HeaderViewModel too. You can then reference the properties of this common HeaderViewModel in the bindings in the View, using binding '.' notation.
If you are using Unity with Prism, you can create this shared instance HeaderViewModel in the OnInitialize override of the App.
Create a shared part for each Page/View as a UserControl, which can be positioned on each page in the same place. This enables you to bind to the same properties on your HeaderViewModel.
I just want to know if this is the proper way to go about splitting up widgets in GWT that get too large, or if I am missing the concept of widgets/proper GWT usage all together.
I started out with a single class (widget), PCBuilder. As PCBuilder became too large, I decided to branch off and make two classes SuggestionPanel, and BuildControlPanel, both of which just split off PCBuilder's code into separate classes that still have access to the methods in PCBuilder:
This way, in my PCBuilder class, I can do something like this to add the SuggestionPanel and the BuildControlPanel to the tabs (TabLayoutPanel) that are specified in the UiBinder of PCBuilder while allowing for SuggestionPanel and BuildControlPanel to have their own separate UiBinder specifications:
My question is: Is this proper? Part of me thinks "no" just because it's not a nice way of doing it. On the other hand it works just fine, and my web application is somewhat broken up into manageable "sections" which is what I wanted.
Thanks for any insight.
It's fine apart from the fact that you have circular dependencies between classes.
Why do SuggestionPanel and BuildControlPanel need to call PCBuilder? Is there any business logic in it? RPC maybe? Separate that into another class.
First, you might want to take a look at GIN - this handles dependency injection. This is good for testability.
Second, if your app goes beyond one "page", then take a look at GWT MVP.
You should not consider your PCBuilder as a widget. Quoting gwt -
You construct user interfaces in GWT applications using widgets that are contained within panels. Widgets allow you to interact with the user. Panels control the placement of user interface elements on the page.
Coming back to your question, my take is to create widgets only if I can reuse the same element more than once. The rest of my layout logic goes into the view. Layout shouldn't be a part of the definition of the widget as much as possible.To conclude, push styling in css, push layout in the views; widgetize only if re-usable (and core) or if adding additional functionality to existing widgets.
I want to add few lines of identical html code to several pages in my web-forms site.
In MVC I know that theres Partial Views that all you have to do is Html.Partial("partial view location"). I dont want to using MVC classes or something like that in my web-forms pages..
And I wonder if theres something like that in web-forms..?
Thanks
UserControl will take care of this. its small reusable pieces of code
This question already has an answer here:
GWT 2.1 Places example without Activities
(1 answer)
Closed 3 years ago.
On an existing project we’re using MVP (hand crafted) reasonably well. It’s understood and does mostly what we need. For a new project I'm looking at using the MVP framework built into GWT 2.1 (Activities and Places).
Our applications are mostly tabbed displays with each tab bound to a single view widget.
I’ve tried to use Activities and Places without success for this type of display. Part of the problem is that the example Hello World article ended up leaving me chasing my tail, too many new concepts for my brain to digest.
The Hello World sample IMO is not a sufficient introduction and doesn’t deal with many of the real world use cases. I was hoping someone could point me in the direction of any sample applications that use MVP for tabbed displays. Thomas Broyer has some excellent posts on his blog but these have still left me a little perplexed.
Previously I’ve used an AppController to handle tabs changes and single presenters for each tab. The new architecture in GWT 2.1 leaves me more confused that it should.
I'm using the gwt Activities/Places framework for a tabbed display, and it works great, BUT: I decided to abandon the TabLayoutPanel widget we had been using and create my own navbar (that looks like tabs) and a content pane. The effect is the same - it looks identical - but the implementation is much cleaner.
I think the problem is in trying to mix Activities/Places, which has its own idea of navigation, with a TabPanel, which has another idea of navigation. At first I tried to throw them together, overriding tab button behavior to trigger a PlaceController, which in turn switched the tabs around, but... it was messy. With the independent navbar / content pane, the PlaceController could do everything just like it wanted to. You just have to manually switch the views, instead of letting a TabPanel do it for you.
I also faced this problem but managed to make it work using one activity per Tab and each activity using a presenter (or more) to display the components of the tab.
Regarding the solution found by Riley Lark, I, instead, opted by using a Decorator pattern and, so, keep the original TabbedPanel. How ? Each activity gets injected (GIN) a presenter that contains a decorator for the TabbedPanel.
So, for example:
Tab1Activity gets injected with Tab1Presenter, which, in turn, gets injected with Tab1Decorator which decorates the TabbedPanel with a Tab1ContentPanel (this panel contains all the widgets to be displayed on the Tab1 tab)
Tab2Activity gets injected with Tab2Presenter, which, in turn, gets injected with Tab2Decorator which decorates the same TabbedPanel with a Tab2ContentPanel (this panel contains all the widgets to be displayed on the Tab2 tab)
Seems complex but, after creating the first decorator, it really paid off and I was able to keep the TabbedPanel and take advantage of the URL history management implicit in the framework.
What is the best approach for navigating between UserControls/Pages(out of browser experience)? I'm fairly new to Silverlight and even newer to the mvvm pattern.
How well does the Navigation Framework Integrate with the MVVM Light Toolkit? A snippet for general application flow control with the two would be great.
The plan was to use the Navigation Framework for general flow or using Jeremy Likeness's approach to region management(http://csharperimage.jeremylikness.com/search/label/regions) and swapping out regions as needed. I've seen a few places mention replacing the Visual Root, but that sounded like a hack to me.
Any advice, snippets, or a nudge in the general direction would be greatly appreciated.
Thank you.
You may find the following post useful:
SL4 Navigation Template with MVVM Light
I had the same problem and found this link (applies to Silverlight too):
Windows Phone 7 — Navigation between pages using MVVM Light Messaging
I'm struggling with the same thing, However, I am kinda steered away from the "NavigationService" because allegedly the journal keeps the object reference in memory or something I read somewhere.
I've been trying to utilize a frame in the main window, and using mvvm light to send navigation messages to the window to change the frame.
Edit: I figured it out.
In the main window (code behind, not viewmodel) I added a Messenger.Default.Register(Of NotificationMessage(Of NavMsg))...
Then in ANY view model I do a Messenger.Default.Send(Of Notificationmessage(Of NavMsg))...
And then I created a NavMsg class which accepts a string uri or an object to navigate to.
Here's some T4 code templates to generate you the code for your view/viewmodel to work with mvvmlight and it demonstrated the closing window message above. http://dl.activeaspsoftware.net/dl.aspx?f=MvvmLightCodeTemplates.zip