I’ll talk today about developing Arabic applications in Windows Presentation Foundation (WPF). The main property for right-to-left display is FlowDirection. FlowDirection is similar to the Windows Forms RightToLeft, but not exactly the same. FlowDirection simply sets the direction and the layout of the control. This includes setting the alignment to the right and the reading order to RTL, in addition, the whole layout of the control flows from the right side to the left.
When you set FlowDirection=RightToLeft of the control. You set the FlowDirection of the child controls, provided that you didn’t set it locally.
<ColumnDefinition Width="0.5*" />
<TextBlock Grid.Column="1"> Hello </TextBlock>
Setting FlowDirection=”RightToLeft” would mean that the, first grid column is on the right-side, while the second-column is on the left –side and the Button and Text block also inherits the same FlowDirection.
So this means, that if you need to develop an RTL application,
1) You need to set FlowDirection very early in the design of your pages.
2) Design your LTR application (for example English) and after you finish the UI design, set FlowDirection and localize your application.
Note: Why am I saying this? because I met with an MVP , who was annoyed that we rearranges the items in the opposite direction when he set FlowDirection=RightToLeft. His case was simple, he started to design his Arabic form and then he realized that some full stops are appearing in the wrong direction (because of the ltr reading). So, he set the RTL property and was puzzled by the flipping that happened. In conclusion, remember to set the FlowDirection property from the start, as soon as you need to develop Arabic applications