View animation Expand and Collapse - Android

This Post helps to animate the android views expand and collapse like Expandable list view.

Find below the code snippet.

ViewAnimationUtils.java

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import android.view.View; import android.view.ViewGroup; import android.view.animation.Animation; import android.view.animation.Transformation; public class ViewAnimationUtils { int animDuration = 600; public static void expand(final View view) { view.measure(ViewGroup.LayoutParams.MATCH_PARENT, ViewGroup.LayoutParams.WRAP_CONTENT); final int targtetHeight = view.getMeasuredHeight(); view.getLayoutParams().height = 0; view.setVisibility(View.VISIBLE); Animation animation = new Animation() { @Override protected void applyTransformation(float interpolatedTime, Transformation t) { view.getLayoutParams().height = interpolatedTime == 1 ? ViewGroup.LayoutParams.WRAP_CONTENT : (int) (targtetHeight * interpolatedTime); view.requestLayout(); } @Override public boolean willChangeBounds() { return true; } }; animation.setDuration(animDuration); view.startAnimation(animation); } public static void collapse(final View view) { final int initialHeight = view.getMeasuredHeight(); Animation animation = new Animation() { @Override protected void applyTransformation(float interpolatedTime, Transformation t) { if (interpolatedTime == 1) { view.setVisibility(View.GONE); } else { view.getLayoutParams().height = initialHeight - (int) (initialHeight * interpolatedTime); view.requestLayout(); } } @Override public boolean willChangeBounds() { return true; } }; animation.setDuration(animDuration); view.startAnimation(animation); } }

Example

TextView description;
Button expand, collapse;
expand.setOnClickListener(new View.OnClickListener() {
 @Override
 public void onClick(View v) {
  ViewAnimationUtils.expand(description)
 }
});

collapse.setOnClickListener(new View.OnClickListener() {
 @Override
 public void onClick(View v) {
  ViewAnimationUtils.expand(description)
 }
});