Fastscroll visibility with auto timeout.

recyclerviewfastscroller/src/main/java/xyz/danoz/recyclerviewfastscroller/AbsRecyclerViewFastScroller.java

@@ -7,6 +7,7 @@
 import android.graphics.drawable.Drawable;
 import android.os.Build.VERSION;
 import android.os.Build.VERSION_CODES;
+import android.os.Handler;
 import android.support.annotation.NonNull;
 import android.support.annotation.Nullable;
 import android.support.v7.widget.RecyclerView;
@@ -36,6 +37,13 @@ public abstract class AbsRecyclerViewFastScroller extends FrameLayout implements
     /** The handle that signifies the user's progress in the list */
     protected final View mHandle;
 
+    private boolean mFastScrollAlwaysVisible;
+    private boolean mIsVisible;
+    private long mFastScrollTimeout;
+    private long mEventTime;
+    private Handler mVisibilityHandler;
+    private Runnable mVisibilityRunner;
+
     /* TODO:
      *      Consider making RecyclerView final and should be passed in using a custom attribute
      *      This could allow for some type checking on the section indicator wrt the adapter of the RecyclerView
@@ -60,6 +68,9 @@ public AbsRecyclerViewFastScroller(Context context, AttributeSet attrs, int defS
 
         TypedArray attributes = getContext().getTheme().obtainStyledAttributes(attrs, STYLEABLE, 0, 0);
 
+        mFastScrollAlwaysVisible = true;
+        mFastScrollTimeout = 10000;
+
         try {
             int layoutResource = attributes.getResourceId(R.styleable.AbsRecyclerViewFastScroller_rfs_fast_scroller_layout,
                     getLayoutResourceId());
@@ -136,6 +147,7 @@ private void setViewBackground(View view, Drawable background) {
     @Override
     public void setRecyclerView(RecyclerView recyclerView) {
         mRecyclerView = recyclerView;
+        addOnTouchListener();
     }
 
     public void setSectionIndicator(SectionIndicator sectionIndicator) {
@@ -171,6 +183,51 @@ private int getPositionFromScrollProgress(float scrollProgress) {
         return (int) (mRecyclerView.getAdapter().getItemCount() * scrollProgress);
     }
 
+    /**
+     * Detect if we touch the recyclerview. Make visible if we did and set to be invisible.
+     */
+    private void addOnTouchListener() {
+        mHandle.setOnTouchListener(new OnTouchListener() {
+            @Override
+            public boolean onTouch(View v, MotionEvent event) {
+                switch (event.getActionMasked()) {
+                    case MotionEvent.ACTION_DOWN:
+                        if (!mFastScrollAlwaysVisible) {
+                            mEventTime = System.currentTimeMillis();
+                            setVisible();
+                        }
+                        break;
+                    case MotionEvent.ACTION_UP:
+                        if (!mFastScrollAlwaysVisible) {
+                            mEventTime = System.currentTimeMillis();
+                        }
+                        break;
+                }
+                return false;
+            }
+        });
+
+        mRecyclerView.setOnTouchListener(new OnTouchListener() {
+            @Override
+            public boolean onTouch(View v, MotionEvent event) {
+                switch (event.getActionMasked()) {
+                    case MotionEvent.ACTION_DOWN:
+                        if (!mFastScrollAlwaysVisible) {
+                            mEventTime = System.currentTimeMillis();
+                            setVisible();
+                        }
+                        break;
+                    case MotionEvent.ACTION_UP:
+                        if (!mFastScrollAlwaysVisible) {
+                            mEventTime = System.currentTimeMillis();
+                        }
+                        break;
+                }
+                return false;
+            }
+        });
+    }
+
     /**
      * Classes that extend AbsFastScroller must implement their own {@link OnScrollListener} to respond to scroll
      * events when the {@link #mRecyclerView} is scrolled NOT using the fast scroller.
@@ -181,7 +238,14 @@ public OnScrollListener getOnScrollListener() {
         if (mOnScrollListener == null) {
             mOnScrollListener = new OnScrollListener() {
                 @Override
-                public void onScrolled(RecyclerView recyclerView, int dx, int dy) {
+                public void onScrolled(final RecyclerView recyclerView, int dx, int dy) {
+                    if (!mFastScrollAlwaysVisible) {
+                        mEventTime = System.currentTimeMillis();
+                        if (dx != 0 && !mFastScrollAlwaysVisible) {
+                            setVisible();
+                        }
+                    }
+
                     float scrollProgress = 0;
                     ScrollProgressCalculator scrollProgressCalculator = getScrollProgressCalculator();
                     if (scrollProgressCalculator != null) {
@@ -245,4 +309,76 @@ public float getScrollProgress(MotionEvent event) {
      */
     public abstract void moveHandleToPosition(float scrollProgress);
 
+    /**
+     * Set whether to always show or use the AbsListView behaviour.
+     * @param scrollAlwaysVisible
+     */
+    public void setScrollAlwaysVisible(boolean scrollAlwaysVisible) {
+        mFastScrollAlwaysVisible = scrollAlwaysVisible;
+        if (!mFastScrollAlwaysVisible) {
+            setInvisible();
+            if (mVisibilityHandler == null) {
+                mVisibilityHandler = new Handler();
+            }
+            mVisibilityRunner = new Runnable() {
+                public void run() {
+                    long end = mEventTime + mFastScrollTimeout;
+                    long time = System.currentTimeMillis();
+                    if (end < time && mIsVisible) {
+                        setInvisible();
+                    }
+                    try {
+                        mVisibilityHandler.postDelayed(this, 333);
+                    } catch (Exception e) {
+                        e.printStackTrace();
+                    }
+                }
+            };
+            mVisibilityHandler.post(mVisibilityRunner);
+        }
+    }
+
+    /**
+     * Set timeout value.
+     * @param desiredTimeout
+     */
+    public void setTimeout(long desiredTimeout) {
+        mFastScrollTimeout = desiredTimeout;
+        if (mFastScrollTimeout < 3000) {
+            mFastScrollTimeout = 3000;
+        }
+    }
+
+    /**
+     *
+     */
+    public long getTimeout() {
+        return mFastScrollTimeout;
+    }
+
+    /**
+     * Get scroll visibility status.
+     * @return scroll visibility status
+     */
+    public boolean getScrollAlwaysVisible() {
+        return mFastScrollAlwaysVisible;
+    }
+
+    /**
+     * Set bar and handle to be invisible
+     */
+    private void setInvisible() {
+        mBar.setVisibility(View.INVISIBLE);
+        mHandle.setVisibility(View.INVISIBLE);
+        mIsVisible = false;
+    }
+
+    /**
+     * Set bar and handle to be visible
+     */
+    private void setVisible() {
+        mBar.setVisibility(View.VISIBLE);
+        mHandle.setVisibility(View.VISIBLE);
+        mIsVisible = true;
+    }
 }