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androidscaleanimation

How to ScaleAnimation to a specific size

I have a view with an starting size (Width1 and Height1). I want to create an animation to change its size to the end size (Width2 and Height2). I have been reading about ScaleAnimation but I cannot understand the scaling factor.

Could you please tell me the values a, b, c & d for the constructor:

ScaleAnimation scaleAnimation = new ScaleAnimation(a, b, c, d);

Thanks

Solution

  • Parameters of 4-floats ScaleAnimation constructor are the following:

    fromX   Horizontal scaling factor to apply at the start of the animation
toX     Horizontal scaling factor to apply at the end of the animation
fromY   Vertical scaling factor to apply at the start of the animation
toY     Vertical scaling factor to apply at the end of the animation

    All values are float--they represent not sizes in pixels, but relative scaling factors. So to scale from width1 to width2 and from height1 to height2 you need to set:

    ScaleAnimation scaleAnimation = 
   new ScaleAnimation(1f, 1f * width2 / width1, 1f, 1f * height2 / height1);