Bidirectional Hot Keys Processing

The system performs some processing for bidi hotkeys. When bidi hotkeys are detected, the system generates WM_CHAR messages containing the appropriate Bidi virtual keys (VK_XX values). The system may also take some default action depending on whether the specific hotkey is enabled or disabled (see below).

Note: The term Enable/Disable of Bidi Hotkey is a bit mis-leading. The effect of disabling a bidi hotkey does not neccessarily disable the hotkey itself - but the system default processing that is associated with this hotkey. For example, when the start push hotkey is disabled the Push Popup is NOT invoked (this is the default action taken by the system for VK_START_PUSH). The WM_CHAR/VK_START_PUSH message is generated in any case.

Whenever the system detects a Bidi hotkey which is enabled, the following actions take place:

• A WM_CHAR message containing the bidi VK value is generated.

• The message containing the hotkey combination is consumed.

• The system performs some default action for relevant hotkeys.

The following is the default action taken by the system for each enabled hot key:

• Set keyboard layer to Latin or National

  The appropriate keyboard layer is set for the window.

• Start push

  The Bidi "Push Popup" IME is invoked.

• End push

  No action is taken.

• Field reverse (toggle)

  Field reverse edit mode is activated.

• Window reverse (toggle)

  No action is taken.

• Activate auto push mode (toggle)

  No action is taken.

• Arabic shape selection hotkeys

  No action is taken.

• Activate Status Indicator

  The Language Viewer is invoked, if one is registered in the system.

Whenever the system detects a Bidi hotkey which is disabled, it does not generate the default action associated with this hotkey. Note that the generation of the VK_ value is NOT suppressed.

The following actions take place:

• A WM_CHAR message containing the bidi VK value is generated.

• The message containing the hotkey combination is not consumed. I.e. applications get both the VK value and the original key combination.

• No default action is performed by the system.

Bidi aware applications that wish to process some hotkeys themselves may choose to disable them in order to prevent the system from taking the default action.

For example, a wordprocessor would probably disable the VK_START_PUSH hotkey, to stop the system from bringing up the push popup dialog, since the application will provide right-to-left typing functionality itself.