ITfIntegratableCandidateListUIElement::OnKeyDown method (ctffunc.h)

Processes a key press.

Syntax

HRESULT OnKeyDown(
  [in]  WPARAM wParam,
  [in]  LPARAM lParam,
  [out] BOOL   *pfEaten
);

Parameters

[in] wParam

Specifies the virtual-key code of the key. For more information about this parameter, see the wParam parameter in WM_KEYDOWN.

[in] lParam

Specifies the repeat count, scan code, extended-key flag, context code, previous key-state flag, and transition-state flag of the key. For more information about this parameter, see the lParam parameter in WM_KEYDOWN.

[out] pfEaten

TRUE if the key event was handled; otherwise, FALSE.

Return value

This method can return one of these values.

Remarks

The OnKeyDown method enables an app to ask query the text service if it wants to process a given key in an integration style. The behavior of the OnKeyDown method can depend on the integration style. If the text service returns *pfEaten=TRUE, then the app should do no processing of the key. If FALSE is returned, the app can perform its own action in response to the key.

GUID_INTEGRATIONSTYLE_SEARCHBOX ({E6D1BD11-82F7-4903-AE21-1A6397CDE2EB}) enables an implementation of a keyboarding experience in which the user can move perceived keyboard focus from the search box to the candidate list to search suggestions. The text service can process keys like VK_UP and VK_DOWN before Search handles them to change its internal state.

Requirements

See also

ITfIntegratableCandidateListUIElement