WP7 - Databinding + Italics + Wordwrap issue - silverlight

Here is what I am trying to do. I can't seem to be able to figure out a solution yet:
I have 2 string data sources from a webservice and on the front end I want to combine them into a single sentence separated by a comma.
The first part I want in normal font, the second part I want in italics
I also want the sentence to word wrap
I am using MVVM so I want to some how bind these string data sources to a textblock some how...
The cases I want to be able to handle:
Normal:
ex. This is the sentence part 1, this is the sentence part 2
No second part so no comma
ex. This is the sentence part 1 I still want this to be able
to word wrap
The second part word wraps
ex. This is the sentence part 1, this is the sentence
part 2 wrapped to second line
Also
Second Part only with word wrapping
First part wordwraps followed by the second part
There seems to be no easy solution.
The one that I can think is have a PropertyChangedEventHandler which notifies me when those strings were returned from the webserver, then format the string in codebehind...

In order to achieve the effect that you are trying to achieve continuous word wrapping with the italic formatting can only sensibly be achieved by using the <Run> element within a TextBlock. However, you cannot bind the contents of a Run element, so you will need to create this in code.
Assuming that you get two separate responses from the web service (they don't come back from a single call), then you cannot rely on which one will come in first, so I would use event aggregation to notify the view from the view model when all the necessary data has been received. The PRISM library for WP7 includes an implementation that you can use to achieve the effect (note that PRISM for WP7 is much lighter than it's WPF or Silverlight counterparts).
In response to the event, your view can pull the properties from the view model, create the TextBlock and it's component Run elements, and then update accordingly. In fact, when you subscribe to an event using PRISM, you can specify that the handler for that event is run on the UI thread, which will no doubt help.

Related

Protecting custom inline elements in WPF RichTextBox

I'm currently spiking with the WPF RichTextBox before I decide whether or not it can be used in a project of mine.
What I need is to have elements of text representing various objects (other texts or objects), a bit like a WIKI but not quite. Clicking on such a text will make stuff happen, like navigating to other texts or providing additional options.
Anyway, as these little text bits represent other objects I would like to protect them but I have succeeded with this only in part: The user cannot position a caret inside such a text element and edit/delete it but it is still possible to make a selection and delete/replace it, including my custom elements.
Have anyone travelled down this road with the RichTextBox? My latest experiment was to simply record all custom text elements when being part of a selection and then restoring them after the (destructive) edit. That fell apart because I can't find a way to re-insert my custom inline elements (derived from the Run class). The only way I've found to programmatically insert a Run (based) element at a specified position (TextPosition) is via its constructor.
Well, any hints would be greatly appreciated.
You are really looking for a FlowDocument, not a RichTextBox.

WPF Printing multiple pages from a single View Model

I am currently a little bit troubled by the following problem. I have a user interface which basically shows a graphic (a canvas made of Lines, Circles, ... these are all WPF objects). Depending on the selection a user makes in the menu, some items get deleted and some get added. So the basic image looks the same, but a few modifications are made.
The user has the possibility to select - say - 10 different "pages" by clicking a Next/Previous Button.
I am using MVVM Light and my ViewModel contains all the items of the graphic (all Lines, ...).
Now I would like to print that graphic to multiple pages. The first page should contain the graphic with changes from page 1, the second page contains the graphic with changes from page 2 and so on. The actual number of pages is dynamic. I track this with a property CurrentPage and a property PagesTotal.
Whenever I push the "Next" button, this causes a command to be executed which will change the variable CurrentPage and also makes sure that the correct items are displayed.
Now I would like to print this but this is where I'm stuck. I dont' mind leaving the MVVM zone and doing some dirty work in code-behind but I would refuse to draw everything again like in the old GDI days.
Any ideas are really welcome.
Create a UserControl containing your display logic (you graphic, for instance). Grab you ViewModel list and project then in UserControls, setting each ViewModel as each UserControl's DataContext.
Force each one to render calling Measure with infinite value and then Arrange with the resulting DesiredHeight and Width. Then follow the procedures to print WPF visuals (link link link).
Essentially, this should be quite simple if and only if your views work independently; i.e. your ViewModel doesn't contain UiElements that are placed into your View.
Simple solution is to basically print your visual root. If need be encapsulate your Views in a user control first.
PrintDialog printDlg = new PrintDialog();
UserControl1 uc = new UserControl1();
printDlg.PrintVisual(uc, "User Control Printing.");
Reference
Alright, I have to admin that I now switched back to doing the printing through code only. I would have really liked doing it "WPF-style" but handling the multiple pages issue was just too much trouble.
Anyway, there is still one issue regarding the printout left but this will be another question.

How does the ExtJS4 Column class work?

I wrote my own sub-class, for some selection stuff and paging etc. But those all worked with the renderer(), which required them to return a string.
This worked fine, I created some image-tags and returned those.
But how does this class work in detail?
I want a sub-class which displays a chart in a cell, which should technically be no problem, but the renderer() doesn't seem the right place for it, since it only works for strings.
Does the Class get instantiated for every row? or is it really just one instance for a column, which methods get called for every row with the needed data and the instances don't hold any state about the rows?
The renderer() mechanism is actually implemented in Ext.grid.column.Column, for which there is one per column.
As you have mentioned, the renderer() function returns a string, which could be an HTML string (which could be rather complex - have a look at the templates used by ExtJs for the standard columns). But you cannot return a component (chart).
To the best of my knowledge (based on my own understanding and replies to similar questions), ExtJs does not offer a straight-forward way to render components within grid cells. If you really think about it - you are asking a grid for much more than its intended role. It was designed to present records per raw, with the addition of simple user interaction facilities, like checkboxes.
But what you are really asking for is more of a way to layout charts, for which problem i suggest you look into the Table layout.
Alternatively you should be able to render a chart into a dom element, which will be defined in your own custom column template. But I will consider this to be an involved task.

Complex .Net 2.0 Windows Forms control: where to start?

In order to make a convenient UI for an .Net 2.0 Winforms application I am working on, I have need for a control that I'm pretty sure goes beyond the "out of the box" behavior of any standard control. A mock-up of what I'm trying to achieve follows:
Mock up http://www.claware.com/images/temp/mockup.png
Essentially, this part of the application attempts to parse words into syllables from tribal languages (no dictionary to refer to; any and all unicode characters are possible.) By the time the user gets this far, he has already defined the vowels / consonants in his language and some other configuration. There is then an iterative process of (1) the application guesses which syllables exist in the language based on some rules, (2) the user refines the guesses, selecting the correct parsings or manually parsing a word, (3) the application "learns" from the user's feedback and makes smarter guesses, (4) repeat until the data is "good enough" to move on.
The control needs to present each word (the grey headers), then all the syllable break guesses (the white areas with dots separating the parts of words.) There is also a way to manually enter a parsing, which will display a text area and save button (at the bottom of the mockup.) When the user hovers over a guess, the background changes and "accept / reject" buttons appear. Clicking on the accept, or entering a manual parsing, removes the entire word from the list. Clicking the reject button removes just that item.
I'm by no means 100% sold on the formatting I have above, but I think you can get a general idea of the types of formatting and functional control I need. The control will also scroll vertically--there may be thousands of words initially.
My question for you experienced WinForms developers is: where to start? I would really, really like to stay within the .Net core framework and extend an existing control as opposed to a third-party control. (At the risk of starting a religious war: yes, I suffer from NIH-syndrome, but it's a conscious decision based on a lot of quick-fix solutions but long-term problems with 3rd party controls.) Where can I get the most "bang for my bucK" and the least reinventing the wheel? ListView? ListBox? ScrollableControl? Do I need to go all the way back to Control and paint everything manually? I appreciate any help that could be provided!
[Edit] Thanks everyone for the ideas. It seems like the most elegant solution for my purposes is to create a custom control consisting of a FlowLayoutPanel and a VScrollBar. The FlowLayoutPanel can contain instances of the custom controls used for each word. But the FlowLayoutPanel is virtual, i.e. it only contains those instances which are visible (and some "just out of scroll"). The VScrollBar events determine what needs to be loaded. A bit of code to write, but isn't too bad and seems to work well.
I would look at the TableLayoutPanel and FlowLayoutPanel controls. These will let you organize a series of controls with moderate ease in a vertical fashion. I would then create a UserControl that consists of a label and 2 buttons. The UserControl will expose properties like Text and events that are exposed for the button clicks.. For each entry in the list, you will create an instance of the UserControl, assign the text value, and handle the click events. The instance will be placed in the Table/Flow panel in the correct order. Both of those layout panels do allow for inserting items between other items so you can add/remove items from the list dynamically.
Edit:
Given the length of what you are trying to render, I would consider using the DataGridView and do some custom rendering to make it perform how you want it to work. Using the rendering events of the DGV you can merge columns, change background colors (like highlighting the dark gray lines), turn on/off the buttons, and handle changing the grid into edit mode for your rows to allow modification or inserting of new values. This method would easily handle large datasets and you could bind directly to them very easily.
Well, this certainly looks like a candidate for a custom component that you should be creating yourself. You can create this using standard .Net drawing commands along with a text-box, and a regular button control.
Now you want to find out where to start.
Create a Windows Forms Control Library project.
Drop in the textbox and the button control.
The panel drawing code should preferably be done by code. This can be done using the regular GDI+ commands.
Edit:
Here's another idea, and one that I've practically used in my own project with great success.
You could use a web-browser control in the app, and show your data as html. You could update the source of the web-browser control based on the input in the textbox, and clicking on the links in the web browser control will give you the event that you can trap to do some action. Your CSS will work.
I used this technique to build the 'desktop' in an app I made called 'Correct Accounting Software'. People loved the desktop so much that it is one of the best loved features of the app.
Here's how I would do it:
Create a custom control. In this custom control, have a ListBox atop a LinkButton, and when the LinkButton is clicked you can make it give way to a TextBox. The ListBoxes will have the top row unselectable... you can probably get the rest from there. When you get your list of words, fill a Scrollable of some kind with one control for each word:
(foreach String word in words){
myScrollable.add(new MyComponent(word));
}
From there, I'm not sure what you want to do with the boxes or the data, but that's my initial idea on the UI setup.
Use the WebBrowser control and generate the HTML markup into it using DocumentStream or DocumentText.

Should path recursion occur in a class or presentation layer?

I have a WinForms app with an input textbox, button, and a multiline output textbox.
A root path is entered in the textbox. Button click calls a function to recursively check all subdirectories for some proper directory naming validation check.
The results are output into the multiline textbox.
If the recursive work is done in a separate class, I have two options:
Keep track of improper directories in a class property(e.g. ArrayList),return the ArrayList when done, and update the output textbox with all results.
Pass in ByRef the output textbox and update/refresh it for each improper directory.
Even though 1 & 2 are single-threaded, with 2, I would at least get my results updated per directory.
If the recursive work is done in the presentation layer and the validation is done in a separate class, I can multithread.
Which is a cleaner way?
You don't need to pass the TextBox ByRef. It's already a reference object. Passing it ByRef would only have an effect if you planned to assign a different or new TextBox to the reference.
If you're going to do the work in a separate class, it seems as simple as passing in the contents of the TextBox as a string, and getting the results back as a string or a set of strings (array or List<string> or the like). This is better than passing in the TextBox in case someday you decide to use a different kind of control to store this information.
I would suggest something close to option 1. I would have a method that takes the root directory as an input and returns a List of directories that are "bad". Also I would call that method on a background thread so as not to hang the UI while the operation is being performed. Add a progress bar or some sort of wait indicator so the user knows that the operation is ongoing.
Passing the textbox into the method wouldn't allow you to reuse that method for anything else. In the interest of code re-use (if that's important to you) I think it's cleaner to simply have the method return a list and let the callback method figure out how to display the data.
[not sure if this is the place for a follow up to the original question]
so, is it safe to say that a recursive business layer function will not be able to update a presentation level control at each recursive iteration?

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