Incorrect bidi behaviour in WPF? - wpf

I experience strange things when setting the "Language" property in WPF:
Set FlowDirection to "RightToLeft" on a Window or textbox/textblock
Set the Language property to "fa-IR"
Set the text to one of the sample texts below (A, B)
A. This text does not render correctly in WPF 3.5:
فاکس: ‎+44 1908 215040
It works with WinForms and Silverlight. Note that it contains a 'LEFT-TO-RIGHT MARK' (U+200E)
Here is a HTML version of the above with numeric character references to LRM, to visualize where the LRM is inserted:
فاکس: ‎+44 1908 215040
B. This text does render correctly in WPF:
فاکس: ‎+‎44‎ ‎1908‎ ‎210210
But it contains (I believe) unncessary LRM characters. I put together the text in a trial-and-error fashion.
Here is the HTML version with the extra LRM characters
فاکس: ‎+‎44‎ ‎1908‎ ‎215040‎
Why are the extra characters needed / what am I doing wrong with the original text?
Note: The problem occurs IFF setting the Language property, either explicitly in XAML or code (like Language="fa-IR") or by overriding the default value of the Language property in code (assuming current culture being "fa-IR") as so:
FrameworkElement.LanguageProperty.OverrideMetadata(typeof(FrameworkElement),
new FrameworkPropertyMetadata(XmlLanguage.GetLanguage(CultureInfo.CurrentCulture.IetfLanguageTag)));
If I leave the language property as en-US, the text renders correctly in WPF, but I really need to set the Language to have value conversions work without having to set the ConverterCulture explicitly on each and every data binding that could be binding to some culture dependent data.
There are also other problems, like LRO ('LEFT-TO-RIGHT OVERRIDE' (U+202D)) being ignored.
I really need help understanding what is going on, as this could turn out to be a show stopper for localizing my application to Persian and Arabic.
I suspect that I am the one doing something wrong, as I fail to google for the problem.
Here is a a related post on MS Connect, but no one has so far confirmed the behaviour as a bug:
http://connect.microsoft.com/WPF/feedback/details/682784/incorrect-unicode-bidi-behaviour#
Note: I am not that familiar with the BiDi algorithm in general and know even less of the actual implementation in WPF. I have a basic understanding of Unicode.

Related

Visual Studio breaks Visual Inheritance

I have made a FormBase, from which I inherit a FomBaseList and a FormBaseDetail.
All other forms in the project are derived from FormBaseList or FormBaseDetail.
Now it seems that VS has huge problems with that, and my biggest problem is that VS keeps writing property values from the Ancestor form into the designer.cs from the child form.
for example, in FormBaseList I have this property/value :
this.gttDXGridView1.OptionsView.ShowAutoFilterRow = true;
I expect that in a derived form, for example FormClientList, there is no mention for this value in the designer.cs, because it should fetch the value from its parent. In other words, just plain simple basic OOP.
And I also expect that when I change the property in FormClientList to
this.gttDXGridView1.OptionsView.ShowAutoFilterRow = false;
that this is seen as an override from the baseclass.
However, VS keeps overwriting the property in FormClientList.Designer.cs with the value found in FormBaseList.Designer.cs.
This breaks the rules of OOP in my opinion, other tools that support Visual Inheritance like Delphi for example do this correct.
How can I stop VS from doing this ?
The properties are changed using the designer.
All controls are DevExpress controls, or derived from a DevExpress control.
Another example, which works just opposite so its very strange.
For example put a Button on the BaseForm and give it an image.
The button with the image appears on all derived forms.
Now change the image on the button of the BaseForm.
You would expect the image to change on all derived forms also, but that does not happen.
I discovered that again VS has written the property value of the button in all derived designer.cs files, and this time it does not overwrites them.
I created a ticket about this at the DevExpress forum, and they where able to reproduce it.
It is now passed on to their developers.
https://www.devexpress.com/Support/Center/Question/Details/T692940/devexpress-controls-break-visual-inheritance-in-visual-studio
It also seems I was not the first to report a similar problem.
https://www.devexpress.com/Support/Center/Question/Details/T692244/imageoptions-are-serialized-in-a-successor-when-visual-inheritance-is-in-effect

Markup extension breaks on upgrading from Extended WPF Toolkit to 2.0

This is a problem I ran into after upgrading, for unrelated reasons, from version 1.9.0 to 2.0.0 of the Extended WPF toolkit. Despite some time spent bashing my head against it, I'm still not sure whether the problem is with it, with my code, or just something no-one thought of at the time.
I had, previously, a PropertyGrid style that set up type-based custom editors for several different data types, using the TargetType property of the EditorDefinition. This obviously didn't work under 2.0.0, inasmuch as EditorDefinition is obsoleted, so, per the warning messages given, I rewrote the style using EditorTemplateDefinition and TargetProperties, thus:
https://gist.github.com/cerebrate/6695088
Here's the problem. If I comment out the upper two EditorTemplateDefinitions, those using the {arkane:Nullable} markup extension, the remainder of the style (the two definitions using the {x:Type} markup extension) works. If I leave them in, as soon as the window containing the property grid is shown, the application crashes with a XamlParseException, could not convert System.RuntimeType to IList.
The {arkane:Nullable} is a simple but pretty standard - or at least commonly seen - extension to TypeExtension to provide the ability to use nullable types in XAML:
https://gist.github.com/cerebrate/6695095
But more to the point, it's a simple subclass of TypeExtension and worked just fine when applied to TargetType in EditorDefinition, and hasn't been changed since.
Any ideas as to what part of the change broke this and how to fix it, on either end?
Or, alternatively, is there any way to associate a custom editor for the Extended WPF Toolkit PropertyGrid with a nullable type without using such a markup extension?

WPF Undo Redo Property System to highlight in red color if value has changed

I have a following requirement for a very complex UI. (Complex here means there are lot of controls in the form [approximately 100]). I am using MVVM (if my problem requires it to slightly go away from MVVM I am ok with it)
My question is for Editable ComboBox and TextBox. But I would say I like to hear a common algorithm which will fit all controls.
Requirement 1 : The user edits the content and goes to next control, the color of the control/text should become red.
Requirement 2 : When the user comes back to the previously edited control and enters the value which was initially present, the color of the control/text should become back to black.
I know the requirement is tough and I have been breaking my head to design a generic algorithm using which I can store the previous value and call a function to change the color of control.
To just give you all an idea, --> I tried storing 2 properties for every TextBox like Default_Text and Text. But since the number of properties are huge, the memory footprint is very huge. Also maintaining so many properties is very tough.
--> I tried adding a Dictionary to every ViewModel to store what values have got changed. But here the problem I faced was giving unique keys to all the controls in my application, which is not very helpful
--> I had even thought and tried about subclassing controls like TextBox, ComboBox and overriding some methods to suit my requirement, but sadly I failed miserabley when I started adding validations and all.
So here I am stuck with designing a generic WPF property system/algorithm to handle all undo redo functionality, changing styles of controls,etc!!!
It will be really great if you experts can guide me in right direction and also help me in developing such an algorithm/system. A sample illustration will be nice though!!!
I found an answer to the above problem. I used attached behavior for this. More details on this link Function call from XAML from StackOverFlow.
When I databind, I store the initial value of the DataBound variable in the Tag property by using Binding=OneWay. Then I have written a attached behaviour for LostFocus event. Whenever the user enters a control and then goes to other control, it fires LostFocus event and calls my attached behaviour. In this, I check whether the value is equal to the value in Tag. If it is same, I display in black else I display in red.
Attached Behaviour rocks in WPF. I can achieve anything from that cleanly without code cluttering!!!!
Another alternative is to use some "dirty" tracking in your models (or viewmodels) and bind to a properties isdirty (and convert it to a color).

Serializing WPF RichTextBox to XAML vs RTF

I have a RichTextBox and need to serialize its content to my database purely for storage purposes. It would appear that I have a choice between serializing as XAML or as RTF, and am wondering if there are any advantages to serializing to XAML over RTF, which I would consider as more "standard".
In particular, am I losing any capability by serializing to RTF instead of XAML? I understand XAML supports custom classes inside the FlowDocument, but I'm not currently using any custom classes (though the potential for extensibility might be enough reason to use XAML).
Update: I ended up going with RTF because of its support for text-encoded embedded images. XAML doesn't seem to include image data in its encoding, and XamlPackage encodes to binary, so RTF just works better for me. So far I haven't noticed any lack in capability.
If all your users are doing is typing in the RichTextBox and doing character formatting, RTF is as good as XAML. However there are many FlowDocument capabilities you may expose in your UI that are not convertible to RTF.
Here are some examples of FlowDocument (and RichTextBox) features that are not expressable in RTF or are implemented differently:
A Block can have an arbitrary BorderBrush, including gradient brushes with stops, VisualBrush
A Section has the HasTrailingParagraphBreakOnPaste property
Floater / ClearFloaters is implemented differently
Hyphenation can be enabled/disabled per block, not just per paragraph
WPF Styles and ResourceDictionaries can be included in the Resources property
Arbitrary WPF UI such as bound CheckBoxes, etc, can be embedded inside the RichTextBox and can be cut-and-pasted from other windows.
For example, suppose you want to allow users to drag or cut/paste in a "current date/time" field into your RichTextBox that would always show the current date and time. This could be done by adding a second read-only RichTextBox that has the InlineUIContainer and the already-bound control. This even works when cutting and pasting from other applications and does not require custom controls.
Another consideration is that the code to convert between FlowDocument and RTF is relatively complex so it may have lower performance than going with XAML. Of course loose XAML doesn't include images and such - for that you need to use XamlPackage. I store my XamlPackage in the database as a byte[], but you can also choose to Base64 encode it for storage as a string.
The bottom line is that it really depends on whether you want the user to be able to use features not available in RTF. Even if your application doesn't include tools to generate FlowDocuments that use these features, it is possible to cut-and-paste them from other applications.
Be aware that in Wpf RichTextBox's method called TextRange.Save has a bug whereby it loses any end of line terminator. Microsoft will not fix.
https://connect.microsoft.com/WPF/feedback/ViewFeedback.aspx?FeedbackID=478640&wa=wsignin1.0#tabs

WinForms - Localization - UI controls positions different in additional Culture

I did my UI settings.Original language is English. After that I set Localizable property to True. Copied original resx file to frmMain.de-De.resx (for example). Translated all strings. Everything works.
But now I would like to change positions of controls. After that changes are visible only for original/primary Culture (En). When I change Culture to de-De then UI controls are on the "old positions"(?!)
Is this normal behaviour? :O I'm unable to change controls positions on my form after localization?
Can someone explain me this and give some best solution. I really have to change UI design but I don't want to manual copy all translated strings again.
If my description is not clear then I can post source code, just please let me know. I use VS 2008.
Greetz!
If you select the form itself in the designer, and look at the properties there should be a field Language.
Leave this to default when designing the form: this is the default layout for languages without a specific layout. Now, if you want a different layout or even different labels for another language, select the correct culture from the Language property and start designing your form.
By doing so, making changes to the default (in your case english) layout will not be reflected on the specific language's form. This is the way it is supposed to work, the layout of languages is completely separate.

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