android reveal animation jerk observer - android-animation

Question

Hi I am trying to do simple reveal animation in android lollipop. But sudden jerk is observed at the start and end of animation. Can you tell how to overcome this. I tried increasing and decreasing animation duration but it doesn't seems to be working.
package in.ashish29agre.revealfab;
import android.animation.Animator;
import android.animation.AnimatorListenerAdapter;
import android.os.Bundle;
import android.support.design.widget.FloatingActionButton;
import android.support.v7.app.AppCompatActivity;
import android.support.v7.widget.Toolbar;
import android.view.View;
import android.view.ViewAnimationUtils;
public class MainActivity extends AppCompatActivity {
private boolean isViewVisible = true;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
setSupportActionBar(toolbar);
final FloatingActionButton fab = (FloatingActionButton) findViewById(R.id.fab);
fab.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
if(isViewVisible) {
hide(fab, findViewById(R.id.reveal_view));
isViewVisible = false;
} else {
show(fab, findViewById(R.id.reveal_view));
isViewVisible = true;
}
}
});
}
private void show(final View view, final View layoutView) {
// get the center for the clipping circle
int cx = (view.getLeft() + view.getRight()) / 2;
int cy = (view.getTop() + view.getBottom()) / 2;
// get the final radius for the clipping circle
int finalRadius = Math.max(layoutView.getWidth(), layoutView.getHeight());
// create the animator for this view (the start radius is zero)
Animator anim = ViewAnimationUtils.createCircularReveal(layoutView, cx, cy,
0, finalRadius);
anim.setDuration(2000);
// make the view visible and start the animation
layoutView.setVisibility(View.VISIBLE);
anim.start();
}
// To hide a previously visible view using this effect:
private void hide(final View view, final View layoutView) {
// get the center for the clipping circle
int cx = (view.getLeft() + view.getRight()) / 2;
int cy = (view.getTop() + view.getBottom()) / 2;
// get the initial radius for the clipping circle
int initialRadius = layoutView.getWidth();
// create the animation (the final radius is zero)
Animator anim = ViewAnimationUtils.createCircularReveal(layoutView, cx, cy,
initialRadius, 0);
anim.setDuration(1000);
// make the view invisible when the animation is done
anim.addListener(new AnimatorListenerAdapter() {
#Override
public void onAnimationEnd(Animator animation) {
super.onAnimationEnd(animation);
layoutView.setVisibility(View.INVISIBLE);
}
});
// start the animation
anim.start();
}
}

Answer 1

The reveal animation is based on coordinates of the View itself. If the jerk is that the View is suddenly partly hidden while disappearing and suddenly revealed all the way on appear, then that is your culprit. Use:
float cx = getWidth() / 2f;
float cy = getHeight() / 2f;
float radius = (float)Math.sqrt(cx * cx + cy * cy);