First of all, I want to let everyone know that I'm very new to the MVVM concept, and have looked pretty extensively for some explanation of what I want to do, but to no avail.
In the program I'm working on, I have a UserControl with a few buttons on it, which need to control the navigation of the main window. I have 3 different "pages" I want to be able to switch between in my main window. Instead of pages, I decided (for whatever reason, correct me if this is not the best approach) to use a UserControl for each page, and switch the visibility to the correct one. I need the data to persist while switching, so I don't believe that creating new instances of the Usercontrols will work.
My question is: How can I bubble the events from my "NavBarView" to the main window in a way that will allow me to switch the visibility, but in a MVVM way? I know I may be completely going about this the wrong way, and I'm happy to take any suggestions on a better way of achieving this navigation.
I have to use WPF, so WinForms is not an option. Too much transparency and custom controls for WinForms.
I would make the "NavBar" part of the main window if possible and use that to control the sub controls in the forms. I would be careful nesting User Controls. If you can avoid it I would (key indication is are you going to reuse it somewhere else). I took over a project a while back that had a main window with 3 separate highly coupled user controls that had to all work together and it was a nightmare. The only way I could get it to work somewhat safely was to have them all set their data context to the same view model. If I had to do it from scratch - would have taken a completely different approach with a single view.
Related
Let's say I have two "views". Each view has it's own button, which makes other view to appear. All should be managed in one window. So how do I achieve this? Im looking for something like viewController in iOS...
I tried to use one filled, docked panel - but than all classes are active, so it doesn't seem like a good solution. I also tried user classes (like this), it works, but it's complicated and I have big deal sending data between these classes.
There is no such thing as "views" of a form. The concept of what a UIViewController can do in iOS is different than building a properly functioning form in C#. You need to learn some new skills now and approach this from a different perspective.
The basic principle is to build a form with controls (either manually or through code or both), change the properties of those controls manually or through code and use the methods they support. You can do what you want, but it's going to take learning some new things.
Try checking this out:
https://msdn.microsoft.com/en-us/library/360kwx3z(v=vs.90).aspx
It's not 100% clear what you are trying to do, but it sounds like you should look into User Controls or Composite Controls.
I want to create a kiosk mode application using WPF. I want to use a single window because the user should not be able to exit this fullscreen application.
The application should guide the user trough a process. When the user proceeds trough the process, the screen should constantly change and show him the next step.
Usually I just create a single window and use a "state machine" to switch UserControls containing the information for the current step. Is there a better way to achieve this functionality? Maybe I would get a better result using multiple windows or Pages (never used them).
The reason why I am asking is that in future I want to have a simple, clean way of switching the content inside a single window. i.e. I am planning to implement some sort of animation when switching content (like sliding to the next / previous step). I don't want to put more effort into my current approach if it isn't the most flexible and clean one.
Any ideas?
PS: This is about desktop applications. Today I come from the Winforms environment and am experimenting with WPF.
There's a few ways you can achieve this.
First would be to use a Page based application, this will allow you to use a single window. Here is a pretty interesting tutorial
A bonus of using this approach is that navigation between pages is built in.
Your requirements are that you need to use animation for transitioning between pages, as far as I'm aware, using a Page based application cannot achieve this (I may be wrong). So your other option would be to use a UserControl MVVM approach.
This probably won't make a lot of sense now, but here goes:
You can use a single master view model which will hold multiple child view models, each of these could have a visibility property which dictates the visibility of the associated view. The master view model would simply be responsible for displaying the appropriate view model depending on where the user currently is in the application.
Using some clever XAML, you can create storyboards (animations) when the view becomes visible, which will allow you to achieve the crazy awesome animations that you require.
Anyway, that probably didn't make any sense, so here's a tutorial to get you started with MVVM.
Im currently trying to create an application that will require 10+ different "pages" with different content and controls, and i need to switch back and forth between them on particular events.
What ive been doing, is just creating all the different sections in grids, and setting their visibility to collapsed, and then when i need to show them, just switch out the visible grid to the new one.
This has several drawbacks, im assuming its very poor from a coding standpoint, and this pretty much dis-allows me from using the designer at all. (i have no idea what performance implications it has, either)
on top of that, every time i switch to the new page, i need to reset all the components (textbox's etc) to their default states, as they dont get reset by becoming invisible :P
on to my question: i need a way to map out all the different pages, provide visually attractive transitions between them, and be able to use a designer to create them (and i dont mean designing it somewhere and then just copying the xaml)
I had looked around, and ran into SketchFlow and it seemed like the perfect solution, i could fade between pages and map everything on a flow chart easily, and then i realized it was only for app prototypes and i couldnt actually compile it as a normal application... and i needed to inherit from a custom Window class aswell.
is there something out there that allows me to do this? or how can i code this to work properly?
note: this ABSOLUTELY needs to stay within one window. i cant venture out into having 10+ different windows that pop up every time i need to change to something. as this happens very frequently
Split the separate sections in individual user controls. This would allow you to design each of them easily. Then on your form use code to create and load a new instance of particular user control that represents the section you need to show, and when transitioning, load the new section and unload the current. this would allow your form to stay relatively lightweight.
An alternative is to create a navigation application and split your sections into separate XAML view and use the standard navigation service to switch between them.
WPF Navigation Overview
Creating Navigation Applications video tutorial
You might wanna convert your "Pages" to usercontrols and use some transitions like mentioned in the below link to switch between controls
http://www.tanguay.info/web/index.php?pg=codeExamples&id=280
for more on using transitions look here
http://www.japf.fr/2009/04/adding-transitions-to-a-mvvm-based-dialog/
or
http://www.japf.fr/2008/07/8/comment-page-1/
I am working on a WPF app and the UI is getting a bit complex to manage. I am looking for advice on how to maintain it as it grows.
The layout looks something like this
<Grid>
<List of Objects View/>
<Objects Relationship View/>
<Object Details View />
<Multiple Objects Details View/>
<View 5 />
<View 6 />
:
:
</Grid>
Each view gets created (visibility hidden) and bound to some complex data, when the window is constructed. I want only one view visible, to the user at a time. I do this by manipulating visibility.
But the problem is the transition between views doesn't involve just fliping Visibility. It involves rebinding with currentdata, stoping background threads/timers and starting new ones (and possibly some binding again) that support the newly selected view. So what's happening is with every new view I add, I am adding a whole bunch of code to take care of all the possible transitions.
Is there some pattern I can use to deal with this kind of scenario?
Also is there some way I can avoid creating and hiding everything at app load and using visibilty as a controller?
Any help is greatly appreciated. Thanks!
May I ask how you are allowing the user to switch back and forth between the views? Is it a key combo? Mouseclick?
Not that it's answering your question per se, but my suggestion is that this sounds like a perfect scenario for a tab control. And with WPF, it doesn't necessarily have to look anything like a tab control.
If you use a TabControl, it opens up the possibility of using the SelectionChanged event coming off of the TabControl to allow you to tell background threads to stop and you can unload anything that you need to unload.
Depending on how you use the TabControl, the UI can be somewhat virtualized. What that means is that whenever a tab is unselected all of the UI for that tab is destroyed and recreated the next time it's selected. It will behave this way if you use the MVVM or PresentationModel pattern and load ViewModels as the items for your TabControl and use DataTemplates for the views. If you just put TabItems into the TabControl with controls inside of them, it will not behave this way, however.
As far as patterns are concerned, I'd definitely recommend MVVM. It may take a bit of time to catch up to it and understand it, but I'd never do WPF without it. If you need anymore resources or examples, let me know.
edit:
I reread your question and noticed that you may be in need of another type of navigation. If you've got views that are needing to make transitions to other views based on user actions and you don't want all of the views to be presented to the user so that they can select which one they want to look at (like the TabControl will do), you may want to look at WPF Navigation. Navigation is basically something that MS added in with WPF to allow browser style navigation in a WPF app. This MSDN article should be a good resource on that kind of thing.
This sounds like a problem well suited to Composite WPF (Prism). You can define your main area as a region, and use a SingleActiveRegion to show one view at a time. If you create your own region adapter, you can do all the maintenance when the active view changes.
Also, adding a new view won't involve changing the hosting view's code. This will allow you to deploy additional views in the future in separate assemblies...
I'm writing an application that is basically just a preferences dialog, much like the tree-view preferences dialog that Visual Studio itself uses. The function of the application is simply a pass-through for data from a serial device to a file. It performs many, many transformations on the data before writing it to the file, so the GUI for the application is simply all the settings that dictate what those transformations should be.
What's the best way to go about designing/coding a tree-view preferences dialog? The way I've been going about it is building the main window with a docked tree control on the left. Then I have been creating container controls that correspond to each node of the tree. When a node is selected, the app brings that node's corresponding container control to the front, moves it to the right position, and maximizes it in the main window. This seems really, really clunky while designing it. It basically means I have tons of container controls beyond the edge of the main window during design time that I have to keep scrolling the main window over to in order to work with them. I don't know if this totally makes sense the way I'm writing this, but maybe this visual for what I'm talking about will make more sense:
Basically I have to work with this huge form, with container controls all over the place, and then do a bunch of run-time reformatting to make it all work. This seems like a lot of extra work. Am I doing this in a totally stupid way? Is there some "obvious" easier way of doing this that I'm missing?
A tidier way is to create separate forms for each 'pane' and, in each form constructor, set
this.TopLevel = false;
this.FormBorderStyle = FormBorderStyle.None;
this.Dock = DockStyle.Fill;
That way, each of these forms can be laid out in its own designer, instantiated one or more times at runtime, and added to the empty area like a normal control.
Perhaps the main form could use a SplitContainer with a static TreeView in one panel, and space to add these forms in the other. Once they are added, they could be flipped through using Hide/Show or BringToFront/SendToBack methods.
SeparateForm f = new SeparateForm();
MainFormSplitContainer.Panel2.Controls.Add(f);
f.Show();
Greg Hurlman wrote:
Why not just show/hide the proper container when a node is selected in the grid? Have the containers all sized appropriately in the same spot, and hide all but the default, which would be preselected in the grid on load.
Unfortunately, that's what I'm trying to avoid. I'm looking for an easy way to handle the interface during design time, with minimal reformatting code needed to get it working during run time.
I like Duncan's answer because it means the design of each node's interface can be kept completely separate. This means I don't get overlap on the snapping guidelines and other design time advantages.
I would probably create several panel classes based on a base class inheriting CustomControl. These controls would then have methods like Save/Load and stuff like that. If so I can design each of these panels separately.
I have used a Wizard control that in design mode, handled several pages, so that one could click next in the designer and design all the pages at once through the designer. Though this had several disadvantages when connecting code to the controls, it probably means that you could have a similar setup by building some designer classes. I have never myself written any designer classes in VS, so I can't say how to or if its worth it :-)
I'm a little curious of how you intend to handle the load/save of values to/from the controls? There must be a lot of code in one class if all your pages are in one big Form?
And yet another way would of course be to generate the gui code as each page is requested, using info about what type of settings there are.