How to deal with big project in WPF - wpf

I am new to WPF environment and I am experiencing some problems like if there are alots of things how do we manage them.for example I have three borders each of same size same location and they contains controls like textboxes etc etc we construct them sequentially but when it comes to edit we get in trouble modifying the border that is at bottom.
So in short how do we manage many controls on single page so that it remains easy to edit

Not sure I completely understand your concerns, but here are several point that make editing WPF UI pretty easy:
Correct usage of layout panels. If you will use approach with absolute positions for each control then it might become a nightmare to move or resize some of your controls. Correct layout (and panels such as DockPanel/StackPanel/etc) might help you a lot.
Incapsulating repeatable parts. WPF has a lot of feature to avoid repeating UI code. I'm talking mostly about Styles and Control templates at the moment. If you have your borders repeating through the entire window, maybe you should think on extracting this border as a ControlTemplate for ContentControl for example?

but I've found that encapsulating controls such as borders, textboxes etc in User Controls helps to keep things well managed (not to mention helps reduce code), similarly using a Resource Dictionary to store styles/animations is useful for very big projects (remember though that the local resources will take precedence when applied so remove them if they not in use)
furthermore, using Layout Panels such as Stacks,Grids and Dockpanels allows you to collapse User Controls when not needed or otherwise (also I've found that for some reason, Grids allow controls to overlap (when items are not correctly ordered in Grid Rows and Columns) which can lead to some elements not being seen in design.
Plan your layout properly and think through which Panels would be best for them, having to go back much later and change can be annoying (though admittedly it happens).
Also remember to use partial classes to properly structure your stuff, having to read through 1000+ lines of code to find something can be a nightmare.

Related

Benefits of Custom WPF Controls

I've thoroughly checked the custom controls topic, spent several hours looking into custom controls written by other people. I've written my own custom button, to feel it better. I've read all the google answers around the "why custom controls", "advanced custom controls examples" and such.
My question is, WHY?
Why would I (or anybody) go through 9 circles of hell to create his own custom control, when one can just adjust an existing control to his needs (using styles and templates). I actually didn't find any explanation on google, just tons of examples, mostly from people who sound even less educated than me.
I imagine there IS such need, when talking about some complicated DataGrid with, I don't know, every cell being a button or something (and still I believe I could do it with a regular DataGrid)... But I've not found anything more complex than a beautiful button. Is there nobody sharing a complicated code on the topic?
There are different levels of element customization in WPF, depending what class you extend from. Each has its own uses and is implemented differently. It is not clear from your question if you are asking about a specific type of control or about all of them in general. So, I will tell you what I think about different ones.
UIElement or FrameworkElement
Extending UIElement gives you the lowest level custom control where you have complete control over the layout and rendering. FrameworkElement is slightly higher level as it does most of the common layout stuff for you while also allowing you to override key parts of it. The main idea with these is that they do their own rendering rather than composing other elements together.
I have made a number of custom FrameworkElements over the years. One example is a ruler similar to one you might find in a program like Photoshop. It has a bunch of properties providing customization for how it is displayed as well as showing markers indicating mouse position relative to the ruler (and a number of other little optional features). I have used it in two different professional projects. I think the main benefit is that it is extremely easy to drop in and set properties/bindings on wherever desired. Build it once, use it over and over.
Control
Extending Control introduces the concept of compositing multiple elements/controls into one reusable component via control templates.
I have used this one less often, but still find it very valuable in the right circumstances. Again, the main benefit here is reusability. You create a control with properties that make sense for what you want to do, then hook up those properties to the properties of the controls in it's control template. Really, this is the same as applying a new template to an existing control, with the added feature of being able to define your own dependency properties. You also have the ability to perform custom logic in the control's code if you need to.
I may be misreading some of your text, but you seem to imply that making a custom control is considerably more difficult than making a control template for an existing control. I have found that the two are nearly identical in most cases using this approach, the only difference being whether you have a code behind you can use.
User Control
A user control is really only slightly different from a custom control practically speaking. Only, instead of defining a control template, you define the visual content directly.
This is probably the most common type of custom control. It is basically the standard method for making XAML based content in a WPF application. These can be reused like other controls, but are more suited for single use such as the content of a dialog or window or something else that is specific to a single application.
Some Other Control
You can also extend an existing control to add additional functionality to it. This way, you still get all the features the control offers and only have to implement the additional bit.
For example, I have a custom control called an AutoScrollRichTextBox that extends RichTextBox. So, it does everything a RichTextBox can do. It also has the ability to automatically scroll to the bottom when content is added to the text box (which it only does if the text box was already scrolled to the bottom before the addition content was added).
I could have implemented that feature as an attached property instead of an extension of the control (and maybe I should have), but it works, and I have used it in three different applications (as an output window and as a chat log). So, I am happy with it.
In the end, it really is just a matter of how self-contained, reusable, and easy to drop in you want a control to be. If there is already a control that does what you want, and you just want it to look different, then you should definitely use styles and templates to achieve that. However, if you want to make something that doesn't already exist, limiting yourself to using only styles and templates will make the implementation work harder and make the end result less reusable and more difficult to set up additional instances (unless all instances are identical).
The examples of making things like buttons that look different are not examples of what you should use a custom control for. They are just examples of how someone would go about making a custom control for the purpose of teaching the details of the process. If you actually want a customized button, just customize a button.

When to use custom user controls

I've got a massive UI that I'm designing. The way that my employer wants it, there are at least 100 labels. Now, I've always thought that in cases like this, breaking up the UI into smaller custom controls was the ideal way to go. However, someone recently told me that custom controls are really only for code re-use. What is the actual suggested practice for this?
EDIT
The finished form will look like this:
Now, I'm using WPF for the UI, and I'm thinking of breaking this down into smaller bits.
Based on your image i see some repetitions, each of this repetitions could be a custom UserControl
But it depends on the usability is it easier to write a custom UserControl so do it but if it would reduce the readability of your code and it also adds additional complexity don't do it
here are an example of what could be separate UserControl's
the green ones are possible useful encapsulations of logic
the orange ones maybe need some not market stuff (don't know enough about your software)
the red ones are the maybe's based on the intern use (from the visual part they are repetitions so the should custom UserControl)
Since your UI is read-only, I'd suggest using a grid.
Are you new to WPF? To break the View into bits WPF offers you CustomControls and UserControls. They are two very similar things yet completely different from each other. CustomControls are Buttons, Labels, TextBoxes, DataGrids...etc. They are basically simple stand-alone controls. UserControls are groups of stand-alone controls serving a purpose such as example a Button and a ComboBox next to each other so user can select something in ComboBox and confirm that by clicking the Button.
If you wish to display data from database I suggest you DataGrid which will give you a table-alike look with rows and columns and all that. If you wish to place few buttons next to DataGrid on which the user may click to insert a new row or to edit a certain cell then I suggest you to wrap all that with a UserControl which you can reuse in other places where you have to display and change data from database too.
You should be using a datagrid and can customize its template to render individual cells as Textblock (lighter version of Label) from a rendering perspective. The main difference between Textblock and Label is very minor things such as access keys and disabled state behavior. But from a WPF object hierarchy - Textblocks are much lighter. But besides that point - from your employer perspective - once you have customized the grid template and render them (so as they look as textblocks/labels) - your employer should have no problems.
Also as somebody suggested above - if you want to logically break sections of the UI since they maybe coming from a different table in db - then User controls is the way to go (for maintainability of code)
Let me know if you are looking for more technical details or need help further technically.
There is nothing wrong in making and using custom controls or user controls or defining some data templates which will be reused depending on how your data is organized.
For sure the UI looks pretty messy and some sort of grid should be used with templates for example where there is similar data. I also have the suggestion and first think about the data and the functionality before starting and let the UI be driven by that. For sure you will the reuse controls/templates. If you think in front on the model and behavior the UI can afterwards more easily changed.
Create your viewmodel correctly, implement the functionality in commands, use bindings, after that the UI will come naturally, reuse controls, use several grids, make the UI more user friendly using several regions, tabs, windows or anything that makes the user more comfortable.

Problems with a big form (50 elements or so) in wpf

I got a pretty big form on a wpf page. I'm putting it together on a Grid, but all the element clutter the page. I figured i'd split out the form into smaller usercontrols and then piece it together on the page as one form. That didn't quite work: SharedSizeScope on a Grid makes the form 'dance'
I could break up the form into a 'wizard style' page, with a next button - dealing with each user control on its own, but i'd rather not break it up into several pages because the end user is used to having it all on one page. Also the validation/storing of data is really a big-bang operation, making it harder to provide feedback if something goes wrong in one of the first pages/usercontrols.
So what now? I'm really tempted to just put all the small elements directly on the page in one big grid. I just feel it's wrong - it will be a maintenance nightmare - i even started thinking 'i wish there were some kind of #region tag in xaml' - that means i know i'm wrong ;)
What can i do?
I would strongly recommend to use nested container controls, like Grids (or other Panels) inside other Grids inside more Grids etc.
It is very common to have several nesting levels, and thus hierarchically split a complex layout into multiple less complex sub-layouts. This makes your layout significantly simpler compared to one big container that tries to do it all (see your failed ShardSizeScope approach).
Once you have created a sensible hierarchy of containers, you may easily use the Visual Studio XAML editor's code collapsing feature to keep track of all your XAML.

WPF CustomControl design advice

I need to develope a WPF custom control to show the layout and connectivity of nodes in a wireless mesh network. The user needs to be able to drag the nodes around. The canvas should grown and Scrollbars should appear as required if elements get draged off the available space. The ability to zoom in/out might be required.
My first take on this is to use a ListBox derived CustomControl with a Canvas based ItemsPanelTemplate. To get things moving Im using Josh Smiths DragCanvas that allows UIElements children of the canvas to be dragged around. My "node" class is not currently UIElement derived (the DragCanvas is currently working with the ListBoxItems that wrap my nodes).
1. Is this a bacially sensible approach or should I be abonding the ListBox idea and going something lower level?
2. I have to overlay the inter node link lines - not currently sure how to go about this (as a UIElement class that is part of the ControlTemplate?)
3. A few people seem to be having a headache with scrolbars in Canvases - is this going to be an issue?
Any general or specific advice most appreciated.
Wow, not bad as a control!
I am doing something similar, but it is not so simple.
1) IMHO, the DragCanvas is a basic way to host+drag elements. Since you will have to host labels (nodes), arcs and labels again (arcs' weight), I think the DragCanvas would be harder than write a custom control by yourself.
Not everything comes easy with templating: sometime is much better the "old" approach winforms-like, or even a hybrid way.
2) As stated, I'd create a Canvas-derived panel, which will host several UIElements (labels, arcs, etc). All of them should be governed by a model+viewmodel. That's a bit harder at the beginning, but it will give you a lot of satisfaction and flexibility in the future.
3) I don't think the Canvas will give you any headache! A Canvas full of elements has always a size of zero. That leads "headaches" for those trying to add a scrollviewer.
Instead, the Canvas-derived class (above) should override the MeasureOverride method, so that its size will fit any of the hosted objects. However, it is a bit annoying the fact you cannot use negative coordinates (it will cause scrolling problems).
It's hard to describe in few lines all the work behind a similar "editor". The task isn't easy, and the problems are many.
Hope it helps, anyway.
Cheers

Is excessive nesting of WPF layout panels (e.g. Grid) computationally expensive?

folks
I have heard from a coworker that I - as a designer using Microsoft Expression Blend - should avoid using excessive nesting of panel elements, because they are computationally expensive.
For example, I tend to create the mainwindow with header and custom statusbar with grid, and then take the top panel and put a grid inside it, and if I have a message inside a rectangle on the already gridded top panel I create yet another grid, etc.
As a very layout-oriented disigner (who wants to use every screen most efficiently whatever the screen dimensions are) I know this is the best way to do it considering absolute control and flexibility, which prevent the window to resize in "unpredictable" ways ;oP
BUT...
...this friend of mine said that, if you have, say, five grids nested inside one another, if you pass the mouse over them, you generate five mouse events, which is costly.
Also, if you have too many calculations due to the too many containers asking for children sizes before the actual rendering, it can also be costly.
I had some previous experience with PyGtk, and I must say I used A LOT o layout panels for all my scripts, and even the resizing of windows never seemed to me to be specially costly, except when I had some complex canvas drawing needed to be recalculated.
Does anyone have any experience or know anything about it?
Thanks a lot for reading
There's no straight-forward answer to this, but obviously the more elements you have participating in layout, the longer the measure and arrange phases are going to take for the window. Depending on which features of which Panel types you use it could be more or less costly, but for sure the more you use the more overhead there will be during the layout calculations. You can learn more about how the layout system works by reading that entire MSDN article.
In the end this is something that, unless you've gone crazy, will not often be an issue. To find out if it is causing problems for your app I suggest using the WPF Performance Suite to do some performance testing.
Wouldn't worry about it that much, i for one did not have problems with it so far. Apply some common sense, what panels are needed in which case? Do you really need yet another panel to achieve your goal or not?
The MSDN article on this issue might be of interest since it explains a few things which are not straightforward: Optimizing Performance: Layout and Design

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