commit f1076dc20feb3ee0c687c818d70ffc1d25bef909
author Brian Attwell <brianattwell@google.com> Tue Aug 12 21:28:21 2014 -0700
committer Brian Attwell <brianattwell@google.com> Thu Aug 14 21:33:35 2014 +0000
tree c02c69c0319ea2451d652950820098a92d721392
parent a6734b9e776ae71a2b9c915f57b12a10fe67d282

QC scrim opacity depends on scroll position

Scrim opacity depends on scroll position after the initial
entrance animation.

This is the last CL needed for b/16683381. Also, this is the
last feature-requestish ui-tweak I plan on doing before
LMP (I promised this one to UX a while ago).

Bug: 16683381
Change-Id: I8a62ff1eda6f2174b50f71f54c4301c111182b7f

src/com/android/contacts/widget/MultiShrinkScroller.java

diff --git a/src/com/android/contacts/widget/MultiShrinkScroller.java b/src/com/android/contacts/widget/MultiShrinkScroller.java
index faa7e41..82b3970 100644
--- a/src/com/android/contacts/widget/MultiShrinkScroller.java
+++ b/src/com/android/contacts/widget/MultiShrinkScroller.java
@@ -9,6 +9,8 @@
 import android.animation.Animator.AnimatorListener;
 import android.animation.AnimatorListenerAdapter;
 import android.animation.ObjectAnimator;
+import android.animation.ValueAnimator;
+import android.animation.ValueAnimator.AnimatorUpdateListener;
 import android.content.Context;
 import android.content.res.Configuration;
 import android.content.res.TypedArray;
@@ -163,6 +165,10 @@
 
         void onStartScrollOffBottom();
 
+        void onTransparentViewHeightChange(float ratio);
+
+        void onEntranceAnimationDone();
+
         void onEnterFullscreen();
 
         void onExitFullscreen();
@@ -560,6 +566,19 @@
         }
     }
 
+    /**
+     * Return ratio of non-transparent:viewgroup-height for this viewgroup at the starting position.
+     */
+    public float getStartingTransparentHeightRatio() {
+        return getTransparentHeightRatio(mTransparentStartHeight);
+    }
+
+    private float getTransparentHeightRatio(int transparentHeight) {
+        final float heightRatio = (float) transparentHeight / getHeight();
+        // Clamp between [0, 1] in case this is called before height is initialized.
+        return 1.0f - Math.max(Math.min(1.0f, heightRatio), 0f);
+    }
+
     public void scrollOffBottom() {
         final Interpolator interpolator = new AcceleratingFlingInterpolator(
                 EXIT_FLING_ANIMATION_DURATION_MS, getCurrentVelocity(),
@@ -588,10 +607,19 @@
                 - (getHeight() - getTransparentViewHeight()) + 1;
         final Interpolator interpolator = AnimationUtils.loadInterpolator(getContext(),
                 android.R.interpolator.linear_out_slow_in);
+        final int desiredValue = currentPosition + (scrollToCurrentPosition ? currentPosition
+                : getTransparentViewHeight());
         final ObjectAnimator animator = ObjectAnimator.ofInt(this, "scroll", bottomScrollPosition,
-                currentPosition + (scrollToCurrentPosition ? currentPosition
-                : getTransparentViewHeight()));
+                desiredValue);
         animator.setInterpolator(interpolator);
+        animator.addUpdateListener(new AnimatorUpdateListener() {
+            @Override
+            public void onAnimationUpdate(ValueAnimator animation) {
+                if (animation.getAnimatedValue().equals(desiredValue) && mListener != null) {
+                    mListener.onEntranceAnimationDone();
+                }
+            }
+        });
         animator.start();
     }
 
@@ -614,6 +642,10 @@
             } else if (!wasFullscreen && isFullscreen) {
                 mListener.onEnterFullscreen();
             }
+            if (!isFullscreen || !wasFullscreen) {
+                mListener.onTransparentViewHeightChange(
+                        getTransparentHeightRatio(getTransparentViewHeight()));
+            }
         }
     }