UICommon: add listener on list scrubber to get notified when it fades in or out

Change-Id: Iad54a1f5db547b09ecffaaba1fb40ffcce1c3749

3 files changed, 153 insertions, 2 deletions

diff --git a/src/com/cyngn/uicommon/animation/FadeUtil.java b/src/com/cyngn/uicommon/animation/FadeUtil.java
new file mode 100644
index 0000000..4446b81
--- /dev/null
+++ b/src/com/cyngn/uicommon/animation/FadeUtil.java
@@ -0,0 +1,82 @@
+package com.cyngn.uicommon.animation;
+
+import android.animation.Animator;
+import android.animation.ObjectAnimator;
+import android.view.View;
+
+/**
+ * Utility for fading a view in and out
+ */
+public class FadeUtil {
+
+    public static final int DEFAULT_FADE_DURATION = 200;
+
+    /**
+     * Makes view visible and transitions alpha from 0 to 1.  Does nothing if view is
+     * already visible.
+     *
+     * @param view
+     * @param duration
+     */
+    public static void fadeIn(View view, int duration) {
+        if (view.getVisibility() == View.VISIBLE) {
+            return;
+        }
+        view.setAlpha(0);
+        view.setVisibility(View.VISIBLE);
+        ObjectAnimator anim = ObjectAnimator.ofFloat(view, "alpha", 0, 1);
+        anim.setDuration(DEFAULT_FADE_DURATION);
+        anim.start();
+    }
+
+    /**
+     * Fade in with default duration
+     *
+     * @param view
+     */
+    public static void fadeIn(View view) {
+        fadeIn(view, DEFAULT_FADE_DURATION);
+    }
+
+    /**
+     * Transitions alpha from 1 to 0 and then sets visibility to gone
+     *
+     * @param view
+     * @param duration
+     */
+    public static void fadeOut(final View view, int duration) {
+        ObjectAnimator anim = ObjectAnimator.ofFloat(view, "alpha", 1, 0);
+        anim.addListener(new Animator.AnimatorListener() {
+            @Override
+            public void onAnimationStart(Animator animation) {
+
+            }
+
+            @Override
+            public void onAnimationEnd(Animator animation) {
+                view.setVisibility(View.GONE);
+            }
+
+            @Override
+            public void onAnimationCancel(Animator animation) {
+
+            }
+
+            @Override
+            public void onAnimationRepeat(Animator animation) {
+
+            }
+        });
+        anim.setDuration(DEFAULT_FADE_DURATION);
+        anim.start();
+    }
+
+    /**
+     * Fade out with default duration
+     *
+     * @param view
+     */
+    public static void fadeOut(View view) {
+        fadeOut(view, DEFAULT_FADE_DURATION);
+    }
+}
diff --git a/src/com/cyngn/uicommon/view/ListScrubber.java b/src/com/cyngn/uicommon/view/ListScrubber.java
index f4e9596..f4517f4 100644
--- a/src/com/cyngn/uicommon/view/ListScrubber.java
+++ b/src/com/cyngn/uicommon/view/ListScrubber.java
@@ -54,6 +54,47 @@ public class ListScrubber extends LinearLayout implements OnClickListener {
     private int mHeaderCount = 0;
     private boolean mFadeInOnMotion;
     private ListScrubberFadeHelper mFadeHelper;
+    private ListScrubberListener mListener;
+
+    public static interface ListScrubberListener {
+
+        /**
+         * Called when list scrubber is beginning to fade in
+         */
+        public void onAppearing();
+
+        /**
+         * List scrubber is fully visible
+         */
+        public void onAppeared();
+
+        /**
+         * Called when list scrubber is beginning to fade out
+         */
+        public void onDisappearing();
+
+        /**
+         * List scrubber is fully gone
+         */
+        public void onDisappeared();
+    }
+
+    /**
+     * Convenience implementation of list scrubber listener that does nothing
+     */
+    public static class DefaultListScrubberListener implements ListScrubberListener {
+        @Override
+        public void onDisappeared() {}
+
+        @Override
+        public void onDisappearing() {}
+
+        @Override
+        public void onAppeared() {}
+
+        @Override
+        public void onAppearing() {}
+    }
 
     public ListScrubber(Context context) {
         super(context);
@@ -187,6 +228,7 @@ public class ListScrubber extends LinearLayout implements OnClickListener {
     public void setFadeInOnMotion(boolean fadeInOnMotion) {
         if (fadeInOnMotion) {
             mFadeHelper = new ListScrubberFadeHelper(mScrubberWidget);
+            mFadeHelper.setListScrubberListener(mListener);
             mFadeHelper.updateState(ListScrubberFadeHelper.State.HIDDEN);
         }
         else {
@@ -230,4 +272,11 @@ public class ListScrubber extends LinearLayout implements OnClickListener {
     public void setHeaderCount(int count) {
         mHeaderCount = count;
     }
+
+    public void setListScrubberListener(ListScrubberListener listener) {
+        mListener = listener;
+        if (mFadeHelper != null) {
+            mFadeHelper.setListScrubberListener(listener);
+        }
+    }
 }
\ No newline at end of file
diff --git a/src/com/cyngn/uicommon/view/ListScrubberFadeHelper.java b/src/com/cyngn/uicommon/view/ListScrubberFadeHelper.java
index 7b20c5c..71530dc 100644
--- a/src/com/cyngn/uicommon/view/ListScrubberFadeHelper.java
+++ b/src/com/cyngn/uicommon/view/ListScrubberFadeHelper.java
@@ -21,6 +21,8 @@ import android.animation.AnimatorListenerAdapter;
 import android.os.Handler;
 import android.view.View;
 import android.view.ViewGroup;
+import com.cyngn.uicommon.animation.FadeUtil;
+import com.cyngn.uicommon.view.ListScrubber.ListScrubberListener;
 
 /**
  * State machine to manage fading the list scrubber in and out when the user interacts
@@ -51,6 +53,7 @@ public class ListScrubberFadeHelper {
     private Handler mHandler;
     private Runnable mFadeOutRunnable;
     private State mState;
+    private ListScrubberListener mListener;
 
     class FadeOutRunnable implements Runnable {
         @Override
@@ -102,19 +105,29 @@ public class ListScrubberFadeHelper {
             case VISIBLE:
                 mScrubber.setAlpha(1f);
                 mScrubber.setVisibility(View.VISIBLE);
+                if (mListener != null) {
+                    mListener.onAppeared();
+                }
                 break;
             case HIDDEN:
                 mScrubber.setAlpha(0f);
                 mScrubber.setVisibility(View.INVISIBLE);
+                if (mListener != null) {
+                    mListener.onDisappeared();
+                }
                 break;
             case FADING_IN:
-                mScrubber.animate().alpha(1f).setDuration(200)
+                if (mListener != null) {
+                    mListener.onAppearing();
+                }
+                mScrubber.animate().alpha(1f).setDuration(FadeUtil.DEFAULT_FADE_DURATION)
                         .setListener(new AnimatorListenerAdapter() {
                             @Override
                             public void onAnimationEnd(Animator animation) {
                                 // strange that this is required...
                                 updateState(State.VISIBLE);
                             }
+
                             @Override
                             public void onAnimationCancel(Animator animation) {
                                 updateState(State.VISIBLE);
@@ -122,7 +135,10 @@ public class ListScrubberFadeHelper {
                         });
                 break;
             case FADING_OUT:
-                mScrubber.animate().alpha(0f).setDuration(200)
+                if (mListener != null) {
+                    mListener.onDisappearing();
+                }
+                mScrubber.animate().alpha(0f).setDuration(FadeUtil.DEFAULT_FADE_DURATION)
                         .setListener(new AnimatorListenerAdapter() {
                             @Override
                             public void onAnimationEnd(Animator animation) {
@@ -149,4 +165,8 @@ public class ListScrubberFadeHelper {
         }
         mScrubber.animate().cancel();
     }
+
+    public void setListScrubberListener(ListScrubberListener listener) {
+        mListener = listener;
+    }
 }