Editing animation behavior between frames

Using the tweening editor, you can define how BlackBerry® Composer determines values between key frames. There are two configurable components that you can adjust to control how the values between key values are calculated:

  • You can change the transition behavior, or motion, across frames. For example, you can specify a transition that starts slowly and then accelerates as each frame passes. Modifying the transition motion is visually apparent when animating position; if you specify an accelerating rate of change, the reference points used to show the object’s position at each frame will initially be close together, then get increasingly further apart.
  • For properties that involve position, such as Translation or Rotation Center, you can adjust the path of the reference points. For example, instead of moving an object along a straight line between two points, you could make it move in a circular motion as it progresses from the starting position to the end position.

You can combine Motion and Path behaviours to produce different results. The following diagram illustrates the use of accelerating motion and curving paths to simulate a bouncing ball. After tweening, the path is curved and reference points are no longer evenly spaced.

A minimum of two property keys (a begin and end value) are required to tween a property.

Previous topic: Changing property keys

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