Android: Collapsing Linearlayout instead of Collapsing Toolbar

Question

I\'m trying to create a Master/Detail transaction in a single fragment. I thought of using LinearLayout as the container of my edittext for my header. Then a RecyclerView fo

Answer 1

Improved my answer using David's comment.

I would animate "topMargin" of your header:

LinearLayout _headerLayout; // expected to be set in "onCreateView"
int _headerHeight; // expected to be set in "onCreateView" as _headerHeight = getHeaderHeight();

Animation _hideAnimation = new Animation() {
  @Override
  protected void applyTransformation(float interpolatedTime, Transformation t) {
    LinearLayout.LayoutParams params = (LinearLayout.LayoutParams) _headerLayout.getLayoutParams();
    params.topMargin = -(int) (_headerHeight * interpolatedTime);
    _headerLayout.setLayoutParams(params);
  }
};

Animation _showAnimation = new Animation() {
  @Override
  protected void applyTransformation(float interpolatedTime, Transformation t) {
    LinearLayout.LayoutParams params = (LinearLayout.LayoutParams) _headerLayout.getLayoutParams();
    params.topMargin = (int) (_headerHeight * (interpolatedTime - 1));
    _headerLayout.setLayoutParams(params);
  }
};

private int getHeaderHeight()
{
  _headerLayout.measure(LayoutParams.MATCH_PARENT, LayoutParams.WRAP_CONTENT);
  return _headerLayout.getMeasuredHeight();
}

Hiding header:

_headerLayout.clearAnimation();
_headerLayout.startAnimation(_hideAnimation);

Showing header:

_headerLayout.clearAnimation();
_headerLayout.startAnimation(_showAnimation);

You can also easily set duration for your animations:

_hideAnimation.setDuration(2000) // will hide in 2 seconds
_showAnimation.setDuration(2000) // will show in 2 seconds