package rehanced.com.simpleetherwallet.utils; import android.view.View; import android.view.ViewGroup; import android.view.animation.Animation; import android.view.animation.Transformation; /** * By Tom Esterez * https://stackoverflow.com/a/13381228/2463984 */ public class CollapseAnimator { public static void expand(final View v) { v.measure(ViewGroup.LayoutParams.MATCH_PARENT, ViewGroup.LayoutParams.WRAP_CONTENT); final int targetHeight = v.getMeasuredHeight(); // Older versions of android (pre API 21) cancel animations for views with a height of 0. v.getLayoutParams().height = 1; v.setVisibility(View.VISIBLE); Animation a = new Animation() { @Override protected void applyTransformation(float interpolatedTime, Transformation t) { v.getLayoutParams().height = interpolatedTime == 1 ? ViewGroup.LayoutParams.WRAP_CONTENT : (int) (targetHeight * interpolatedTime); v.requestLayout(); } @Override public boolean willChangeBounds() { return true; } }; // 1dp/ms a.setDuration((int) (targetHeight / v.getContext().getResources().getDisplayMetrics().density)); v.startAnimation(a); } public static void collapse(final View v) { final int initialHeight = v.getMeasuredHeight(); Animation a = new Animation() { @Override protected void applyTransformation(float interpolatedTime, Transformation t) { if (interpolatedTime == 1) { v.setVisibility(View.GONE); } else { v.getLayoutParams().height = initialHeight - (int) (initialHeight * interpolatedTime); v.requestLayout(); } } @Override public boolean willChangeBounds() { return true; } }; // 1dp/ms a.setDuration((int) (initialHeight / v.getContext().getResources().getDisplayMetrics().density)); v.startAnimation(a); } }