IUIAnimationStoryboard::AddKeyframeAtOffset method (uianimation.h)

Adds a keyframe at the specified offset from an existing keyframe.

Syntax

HRESULT AddKeyframeAtOffset(
  [in]  UI_ANIMATION_KEYFRAME existingKeyframe,
  [in]  UI_ANIMATION_SECONDS  offset,
  [out] UI_ANIMATION_KEYFRAME *keyframe
);

Parameters

[in] existingKeyframe

The existing keyframe. To add a keyframe at an offset from the start of the storyboard, use the special keyframe UI_ANIMATION_KEYFRAME_STORYBOARD_START.

[in] offset

The offset from the existing keyframe at which a new keyframe is to be added.

[out] keyframe

The keyframe to be added.

Return value

If the method succeeds, it returns S_OK. Otherwise, it returns an HRESULT error code. See Windows Animation Error Codes for a list of error codes.

Remarks

A keyframe represents a moment in time within a storyboard and can be used to specify the start and end times of transitions. Because keyframes can be added at the ends of transitions, their offsets from the start of the storyboard may not be known until the storyboard is playing.

Examples

The following code adds a keyframe at a fixed offset of 0.3 seconds from the keyframe at the start of the storyboard.

const UI_ANIMATION_SECONDS offset = 0.3;

UI_ANIMATION_KEYFRAME keyframe1;
hr = pStoryboard->AddKeyframeAtOffset(
       UI_ANIMATION_KEYFRAME_STORYBOARD_START,
       offset,
       &keyframe1
);

Requirements

See also

IUIAnimationStoryboard

IUIAnimationStoryboard::AddKeyframeAfterTransition

IUIAnimationStoryboard::AddTransitionAtKeyframe

IUIAnimationStoryboard::AddTransitionBetweenKeyframes

UI_ANIMATION_KEYFRAME