Add InterpolatorUtils

app/src/main/java/com/hippo/widget/FabLayout.java

@@ -23,8 +23,6 @@ import android.os.Build;
 import android.os.Bundle;
 import android.os.Parcelable;
 import android.support.annotation.NonNull;
-import android.support.v4.view.animation.FastOutLinearInInterpolator;
-import android.support.v4.view.animation.LinearOutSlowInInterpolator;
 import android.util.AttributeSet;
 import android.view.View;
 import android.view.ViewGroup;
@@ -32,12 +30,10 @@ import android.view.animation.Interpolator;
 
 import com.hippo.animation.SimpleAnimatorListener;
 import com.hippo.ehviewer.R;
+import com.hippo.util.InterpolatorUtils;
 
 public class FabLayout extends ViewGroup implements View.OnClickListener {
 
-    private final static Interpolator LINEAR_OUT_SLOW_IN_INTERPOLATOR = new LinearOutSlowInInterpolator();
-    private final static Interpolator FAST_OUT_LINEAR_IN_INTERPOLATOR = new FastOutLinearInInterpolator();
-
     private static long ANIMATE_TIME = 300l;
 
     private static final String STATE_KEY_SUPER = "super";
@@ -276,14 +272,14 @@ public class FabLayout extends ViewGroup implements View.OnClickListener {
             endTranslationY = 0f;
             startAlpha = 0f;
             endAlpha = 1f;
-            interpolator = LINEAR_OUT_SLOW_IN_INTERPOLATOR;
+            interpolator = InterpolatorUtils.FAST_SLOW_INTERPOLATOR;
         } else {
             startTranslationY = 0f;
             endTranslationY = mMainFabCenterY -
                     (child.getTop() + (child.getHeight() / 2));
             startAlpha = 1f;
             endAlpha = 0f;
-            interpolator = FAST_OUT_LINEAR_IN_INTERPOLATOR;
+            interpolator = InterpolatorUtils.SLOW_FAST_INTERPOLATOR;
         }
 
         PropertyValuesHolder translationYPvh = PropertyValuesHolder.ofFloat(