Collapsing toolBar Layout with Viewpager inside NestedScrollView

Question

I am using Collapsing ToolBar Layout with NestedScrollView and Viewpager inside nested Scrollview.

I am having 3 tabs and having 3 fragments for these tabs. These fragments are using RecyclerView to set data.

Now with the nestedScrollView and viewpager, when I scroll the RecyclerView content, the collapsing effect is not working with this.

I need to put NestedScrollView also, as I am having some info that I need to show above Tabs.

Here is my code:

<android.support.design.widget.AppBarLayout
    android:id="@+id/appbar"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:theme="@style/ThemeOverlay.AppCompat.Dark.ActionBar"
    android:fitsSystemWindows="true">

    <android.support.design.widget.CollapsingToolbarLayout
    android:id="@+id/collapsing_toolbar"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    app:layout_scrollFlags="scroll|exitUntilCollapsed"
    android:fitsSystemWindows="true"
    app:contentScrim="?attr/colorPrimary"
    app:expandedTitleMarginEnd="64dp"
    app:expandedTitleMarginStart="48dp"
    app:expandedTitleTextAppearance="@style/TransparentText">

    <FrameLayout
        android:id="@+id/carouselLayout"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        app:layout_scrollFlags="scroll|exitUntilCollapsed"
        android:fitsSystemWindows="true"
        app:layout_collapseMode="parallax">

        <ImageView
            android:id="@+id/coverImage"
            android:layout_width="match_parent"
            android:layout_height="match_parent"
            android:src="@drawable/example"
            android:scaleType="centerCrop"/>

        <LinearLayout
            android:layout_width="match_parent"
            android:gravity="bottom"
            android:orientation="vertical"
            android:layout_gravity="bottom"
            android:padding="@dimen/profile_image_margin"
            android:background="@drawable/gradient_bg"
            app:layout_behavior="@string/appbar_scrolling_view_behavior"
            android:layout_height="wrap_content">

            <TextView
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:layout_marginLeft="@dimen/profile_image_margin"
            android:textSize="@dimen/text_size_xlarge"
            android:textStyle="bold"
            android:textColor="@color/white"
            android:text="Title"
            android:id="@+id/content_title"/>

        </LinearLayout>

    </FrameLayout>

        <android.support.v7.widget.Toolbar
            android:id="@+id/toolbar"
            android:layout_width="match_parent"
            android:layout_height="?attr/actionBarSize"
            app:theme="@style/ActionBarThemeOverlay"
            app:popupTheme="@style/ActionBarPopupThemeOverlay"
            app:layout_scrollFlags="scroll|enterAlways"
            android:background="@drawable/gradient_bg" />

    </android.support.design.widget.CollapsingToolbarLayout>
</android.support.design.widget.AppBarLayout>

<android.support.v4.widget.NestedScrollView
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:layout_gravity="fill"
    android:isScrollContainer="true"
    app:layout_behavior="@string/appbar_scrolling_view_behavior">

    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:orientation="vertical">

        <TextView
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:text="sdjsfksdfsd"
            android:textColor="@color/red"/>

        <TextView
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:text="csdffsfsdfsdfsdf"
            android:textColor="@color/red"/>

        <android.support.design.widget.TabLayout
            android:id="@+id/slidingTabs"
            android:layout_width="match_parent"
            app:tabMode="scrollable"
            app:tabGravity="fill"
            android:layout_height="wrap_content"/>

        <android.support.v4.view.ViewPager
            android:id="@+id/pager"
            android:layout_width="match_parent"
            app:layout_behavior="@string/appbar_scrolling_view_behavior"
            android:layout_height="300dp">

        </android.support.v4.view.ViewPager>
        </LinearLayout>
    </android.support.v4.widget.NestedScrollView>

Please help me if you have any idea how to implement Recyclerview inside NestedScrollview in android, so that I can get this working.

Answer 1

It seems this was already answered here: https://stackoverflow.com/a/31561790/4931825

You can also check out this example provided in the aforementioned answer https://github.com/TheLittleNaruto/SupportDesignExample/

The Author created a custom NestedScrollView class extending NestedScrollView that overrode the onInterceptTouchEvent method like so:

@Override
public boolean onInterceptTouchEvent(MotionEvent ev) {
    final float x = ev.getX();
    final float y = ev.getY();
    switch (ev.getAction()) {
        case MotionEvent.ACTION_DOWN:
            xDistance = yDistance = 0f;
            lastX = ev.getX();
            lastY = ev.getY();
            break;
        case MotionEvent.ACTION_MOVE:
            final float curX = ev.getX();
            final float curY = ev.getY();
            xDistance += Math.abs(curX - lastX);
            yDistance += Math.abs(curY - lastY);
            lastX = curX;
            lastY = curY;
            if (xDistance > yDistance)
                return false;
    }

    return super.onInterceptTouchEvent(ev) || ev.getPointerCount() == 2;
}

and a custom ViewPager class extending ViewPager that overrode its onMeasure method like so:

    @Override
protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec)     {
    super.onMeasure(widthMeasureSpec, heightMeasureSpec);

    int height = 0;
    for (int i = 0; i < getChildCount(); i++) {
        View child = getChildAt(i);
        child.measure(widthMeasureSpec, MeasureSpec.makeMeasureSpec(0, MeasureSpec.UNSPECIFIED));
        int h = child.getMeasuredHeight();
        if (h > height) height = h;
    }
    heightMeasureSpec = MeasureSpec.makeMeasureSpec(height, MeasureSpec.EXACTLY);
    super.onMeasure(widthMeasureSpec, heightMeasureSpec);
}

Finally, he used both inside the CoordinatorLayout:

 <com.thelittlenaruto.supportdesignexample.customview.MyNestedScrollView
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    app:layout_behavior="@string/appbar_scrolling_view_behavior">

    <LinearLayout
        android:id="@+id/lin"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:orientation="vertical"
        android:visibility="visible">

        <com.thelittlenaruto.supportdesignexample.customview.WrapContentHeightViewPager
            android:id="@+id/viewPager"
            android:layout_width="match_parent"
            android:layout_height="wrap_content" />

    </LinearLayout>

</com.thelittlenaruto.supportdesignexample.customview.MyNestedScrollView>