Better interpolators for decelerate animations

app/src/main/java/acr/browser/lightning/activity/BrowserActivity.java

@@ -113,6 +113,7 @@ import acr.browser.lightning.dialog.BrowserDialog;
 import acr.browser.lightning.dialog.LightningDialogBuilder;
 import acr.browser.lightning.fragment.BookmarksFragment;
 import acr.browser.lightning.fragment.TabsFragment;
+import acr.browser.lightning.interpolator.BezierDecelerateInterpolator;
 import acr.browser.lightning.receiver.NetworkReceiver;
 import acr.browser.lightning.search.Suggestions;
 import acr.browser.lightning.utils.DrawableUtils;
@@ -1932,7 +1933,7 @@ public abstract class BrowserActivity extends ThemableBrowserActivity implements
                     }
                 };
                 show.setDuration(250);
-                show.setInterpolator(new DecelerateInterpolator());
+                show.setInterpolator(new BezierDecelerateInterpolator());
                 mBrowserFrame.startAnimation(show);
             }
         }
@@ -1971,7 +1972,7 @@ public abstract class BrowserActivity extends ThemableBrowserActivity implements
                     }
                 };
                 show.setDuration(250);
-                show.setInterpolator(new DecelerateInterpolator());
+                show.setInterpolator(new BezierDecelerateInterpolator());
                 mBrowserFrame.startAnimation(show);
             }
         }

app/src/main/java/acr/browser/lightning/fragment/anim/HorizontalItemAnimator.java

@@ -29,6 +29,8 @@ import android.view.animation.DecelerateInterpolator;
 import java.util.ArrayList;
 import java.util.List;
 
+import acr.browser.lightning.interpolator.BezierDecelerateInterpolator;
+
 /**
  * This implementation of {@link RecyclerView.ItemAnimator} provides basic
  * animations on remove, add, and move events that happen to the items in
@@ -235,7 +237,7 @@ public class HorizontalItemAnimator extends SimpleItemAnimator {
         final ViewPropertyAnimatorCompat animation = ViewCompat.animate(view);
         mAddAnimations.add(holder);
         animation.alpha(1).translationY(0)
-                .setInterpolator(new DecelerateInterpolator()).setDuration(getAddDuration())
+                .setInterpolator(new BezierDecelerateInterpolator()).setDuration(getAddDuration())
                 .setListener(new VpaListenerAdapter() {
                     @Override
                     public void onAnimationStart(View view) {

app/src/main/java/acr/browser/lightning/fragment/anim/VerticalItemAnimator.java

@@ -29,6 +29,8 @@ import android.view.animation.DecelerateInterpolator;
 import java.util.ArrayList;
 import java.util.List;
 
+import acr.browser.lightning.interpolator.BezierDecelerateInterpolator;
+
 /**
  * This implementation of {@link RecyclerView.ItemAnimator} provides basic
  * animations on remove, add, and move events that happen to the items in
@@ -235,7 +237,7 @@ public class VerticalItemAnimator extends SimpleItemAnimator {
         final ViewPropertyAnimatorCompat animation = ViewCompat.animate(view);
         mAddAnimations.add(holder);
         animation.alpha(1).translationX(0).setDuration(getAddDuration())
-                .setInterpolator(new DecelerateInterpolator()).setListener(new VpaListenerAdapter() {
+                .setInterpolator(new BezierDecelerateInterpolator()).setListener(new VpaListenerAdapter() {
                     @Override
                     public void onAnimationStart(View view) {
                         dispatchAddStarting(holder);

app/src/main/java/acr/browser/lightning/interpolator/BezierDecelerateInterpolator.java

@@ -0,0 +1,31 @@
+package acr.browser.lightning.interpolator;
+
+import android.os.Build;
+import android.support.annotation.NonNull;
+import android.view.animation.DecelerateInterpolator;
+import android.view.animation.Interpolator;
+import android.view.animation.PathInterpolator;
+
+/**
+ * Bezier decelerate curve similar to iOS.
+ * On Kitkat and below, it reverts to a
+ * decelerate interpolator.
+ */
+public class BezierDecelerateInterpolator implements Interpolator {
+
+    @NonNull
+    private static final Interpolator PATH_INTERPOLATOR;
+
+    static {
+        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.LOLLIPOP) {
+            PATH_INTERPOLATOR = new PathInterpolator(0.25f, 0.1f, 0.25f, 1);
+        } else {
+            PATH_INTERPOLATOR = new DecelerateInterpolator();
+        }
+    }
+
+    @Override
+    public float getInterpolation(float input) {
+        return PATH_INTERPOLATOR.getInterpolation(input);
+    }
+}

app/src/main/res/anim-v21/bezier_decelerate.xml

@@ -0,0 +1,6 @@
+<?xml version="1.0" encoding="utf-8"?>
+<pathInterpolator xmlns:android="http://schemas.android.com/apk/res/android"
+                  android:controlX1="0.25"
+                  android:controlY1="0.1"
+                  android:controlX2="0.25"
+                  android:controlY2="1"/>

app/src/main/res/anim/bezier_decelerate.xml

@@ -0,0 +1,2 @@
+<?xml version="1.0" encoding="utf-8"?>
+<decelerateInterpolator/>

app/src/main/res/anim/fade_in_scale.xml

@@ -4,7 +4,7 @@
         android:duration="@integer/animation_time_medium"
         android:fromXScale="0.85"
         android:fromYScale="0.85"
-        android:interpolator="@android:interpolator/decelerate_cubic"
+        android:interpolator="@anim/bezier_decelerate"
         android:pivotX="50%p"
         android:pivotY="50%p"
         android:toXScale="1.0"

app/src/main/res/anim/fade_out_scale.xml

@@ -4,7 +4,7 @@
         android:duration="@integer/animation_time_medium"
         android:fromXScale="1.0"
         android:fromYScale="1.0"
-        android:interpolator="@android:interpolator/decelerate_cubic"
+        android:interpolator="@anim/bezier_decelerate"
         android:pivotX="50%p"
         android:pivotY="50%p"
         android:toXScale="0.85"

app/src/main/res/anim/slide_in_from_right.xml

@@ -3,7 +3,7 @@
     <translate
         android:duration="@integer/animation_time_medium"
         android:fromXDelta="100%p"
-        android:interpolator="@android:interpolator/decelerate_cubic"
+        android:interpolator="@anim/bezier_decelerate"
         android:toXDelta="0%p" />
     <!--<alpha-->
     <!--android:duration="@android:integer/config_mediumAnimTime"-->

app/src/main/res/anim/slide_out_to_right.xml

@@ -3,7 +3,7 @@
     <translate
         android:duration="@integer/animation_time_medium"
         android:fromXDelta="0%p"
-        android:interpolator="@android:interpolator/decelerate_cubic"
+        android:interpolator="@anim/bezier_decelerate"
         android:toXDelta="100%p" />
     <!--<alpha-->
     <!--android:duration="@android:integer/config_mediumAnimTime"-->

app/src/main/res/anim/slide_up_in.xml

@@ -3,7 +3,7 @@
     <translate
         android:duration="@integer/animation_time_medium"
         android:fromYDelta="100%p"
-        android:interpolator="@android:interpolator/decelerate_cubic"
+        android:interpolator="@anim/bezier_decelerate"
         android:toYDelta="0%p" />
     <!--<alpha-->
         <!--android:duration="@android:integer/config_mediumAnimTime"-->