title: OnClickListener for the ImageView in side CollapsingToolbarLayout
body: <p>I've got an <code>ImageView</code> inside of a <code>CollapsingToolbarLayout</code> and I'd like to attach a <code>View.OnClickListerner</code> to it. However a click doesn't seem to trigger the listener.</p>
  
  <pre><code>&lt;?xml version="1.0" encoding="utf-8"?&gt;
  
  &lt;android.support.design.widget.CoordinatorLayout
  xmlns:android="http://schemas.android.com/apk/res/android"
  xmlns:app="http://schemas.android.com/apk/res-auto"
  android:id="@+id/view_nade_root"
  android:layout_width="match_parent"
  android:layout_height="match_parent"
  android:fitsSystemWindows="true"&gt;
  
  &lt;android.support.design.widget.AppBarLayout
      android:id="@+id/view_nade_appbar"
      android:layout_width="match_parent"
      android:layout_height="300dp"
      android:background="@null"
      android:theme="@style/ThemeOverlay.AppCompat.Dark.ActionBar"
      android:fitsSystemWindows="true"&gt;
  
      &lt;android.support.design.widget.CollapsingToolbarLayout
          android:id="@+id/view_nade_collapsing_toolbar"
          android:layout_width="match_parent"
          android:layout_height="match_parent"
          android:fitsSystemWindows="true"
          app:contentScrim="?attr/colorPrimary"
          app:expandedTitleMarginEnd="64dp"
          app:expandedTitleMarginStart="48dp"
          app:layout_scrollFlags="scroll|exitUntilCollapsed"&gt;
  
          &lt;ImageView
              android:id="@+id/view_nade_backdrop"
              android:layout_width="match_parent"
              android:layout_height="match_parent"
              android:layout_gravity="center"
              android:scaleType="centerCrop"
              android:fitsSystemWindows="true"
              app:layout_collapseMode="parallax"
              app:layout_scrollFlags="scroll|enterAlways|snap"/&gt;
  
          &lt;android.support.v7.widget.Toolbar
              android:id="@+id/view_nade_toolbar"
              android:layout_width="match_parent"
              android:layout_height="wrap_content"
              app:layout_collapseMode="pin"
              android:paddingTop="24dp"&gt;
  
          &lt;/android.support.v7.widget.Toolbar&gt;
      &lt;/android.support.design.widget.CollapsingToolbarLayout&gt;
  
  
  &lt;/android.support.design.widget.AppBarLayout&gt;
  
  &lt;android.support.v4.widget.NestedScrollView
      android:layout_width="match_parent"
      android:layout_height="match_parent"
      app:layout_behavior="@string/appbar_scrolling_view_behavior"&gt;
  
  
  &lt;/android.support.v4.widget.NestedScrollView&gt;
  
  &lt;com.github.clans.fab.FloatingActionButton
      android:id="@+id/view_nade_fab"
      android:layout_height="wrap_content"
      android:layout_width="wrap_content"
      android:layout_margin="@dimen/activity_horizontal_margin"
      android:src="@drawable/ic_mode_edit_white_24dp"
      app:fab_colorNormal="?android:attr/colorAccent"
      app:fab_colorPressed="?android:attr/colorAccent"
      app:layout_anchor="@id/view_nade_appbar"
      app:layout_anchorGravity="bottom|right|end"/&gt;
  
  &lt;/android.support.design.widget.CoordinatorLayout&gt;
  </code></pre>
  
  <p>Here is the Activity:</p>
  
  <pre><code>@BindView(R.id.view_nade_backdrop) ImageView mBackdrop;
  @BindView(R.id.view_nade_appbar) AppBarLayout mAppbar;
  @BindView(R.id.view_nade_collapsing_toolbar) CollapsingToolbarLayout mCollapsingToolbar;
  @BindView(R.id.view_nade_toolbar) Toolbar mToolbar;
  
  private final View.OnClickListener mOnBackdropClickListener = (v) -&gt;
  {
      final Intent intent = new Intent(ViewNadeActivity.this, GalleryActivity.class);
      intent.putExtra(GalleryActivity.EXTRA_PHOTO_URIS, ListUtils.join(mUtilityData.getImgUris(this)));
      startActivity(intent);
  };
  
  
  @Override
  protected void onCreate(Bundle 
      super.onCreate(savedInstanceState);
      setContentView(R.layout.activity_view_nade);
  
      ButterKnife.bind(this);
  
      setSupportActionBar(mToolbar);
  
      mBackdrop.setOnClickListener(mOnBackdropClickListener);
  }
  </code></pre>
  
  <p>EDIT:
  Here is the <code>OnTouchListener</code> that I attach to the <code>CollapsingToolbarLayout</code> (credit: <a href="https://stackoverflow.com/users/1083957/azizbekian">@azizbekian</a>)</p>
  
  <pre><code>private final View.OnTouchListener mOnToolbarTouchListener = new View.OnTouchListener()
  {
      @Override
      public boolean onTouch(View view, MotionEvent motionEvent)
      {
          int action = motionEvent.getActionMasked();
          if(mBackdropBounds != null &amp;&amp; (action == MotionEvent.ACTION_DOWN
                  || action == MotionEvent.ACTION_UP
                  || action == MotionEvent.ACTION_CANCEL))
          {
              if(mBackdropBounds.contains((int) motionEvent.getRawX(), (int) motionEvent.getRawY()))
              {
                  if(mBackdrop != null)
                  {
                      mBackdrop.dispatchTouchEvent(motionEvent);
                      return true;
                  }
              }
          }
          return false;
      }
  };
  </code></pre>