Hiding/Showing the action bar when scrolling

Question

I'm using ObservableRecyclerView in a Fragment (I'm using fragments because I have tabs in my app). I need the action bar to be hidden/shown based on the scroll of the ObservableRecyclerView. I followed the answer in this question, but it is a bit misleading since I couldn't understand what oldScrollY is.

I tried also this code but it is hiding/showing the bar without animation

@Override
    public void onUpOrCancelMotionEvent(ScrollState scrollState) {
        ActionBar ab = ((AppCompatActivity) getActivity()).getSupportActionBar();
        if (scrollState == ScrollState.UP) {
            if (ab.isShowing()) {
                ab.hide();
            }
        } else if (scrollState == ScrollState.DOWN) {
            if (!ab.isShowing()) {
                ab.show();
            }
        }
    }

EDIT:

activity_main.xml

<android.support.design.widget.CoordinatorLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    android:id="@+id/coordinator_layout_all"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context=".MainActivity">

    <LinearLayout
        android:id="@+id/toolbarContainer"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:orientation="vertical">

        <android.support.v7.widget.Toolbar
            android:id="@+id/app_bar"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:background="@color/primary"
            android:elevation="2dp"
            android:minHeight="?attr/actionBarSize"
            app:theme="@style/ThemeOverlay.AppCompat.Dark.ActionBar" />

        <jo.edu.gju.motassem.seniorproject.SlidingTabLayout
            android:id="@+id/tabs"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:background="@color/primary"
            android:elevation="2dp" />

        <android.support.v4.view.ViewPager
            android:id="@+id/pager"
            android:layout_width="match_parent"
            android:layout_height="match_parent"
            android:layout_weight="1" />

    </LinearLayout>

    <android.support.design.widget.FloatingActionButton
        android:id="@+id/fab"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignParentBottom="true"
        android:layout_alignParentRight="true"
        android:layout_gravity="end|bottom"
        android:layout_marginBottom="16dp"
        android:layout_marginRight="16dp"
        android:src="@drawable/ic_add_white"
        app:backgroundTint="@color/accent"
        app:borderWidth="0dp"
        app:elevation="6dp"
        app:fabSize="normal"
        app:rippleColor="@color/primary" />
</android.support.design.widget.CoordinatorLayout>

fragment.xml

<?xml version="1.0" encoding="utf-8"?>
<FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent">

    <ProgressBar
        android:id="@+id/progress_bar"
        style="?android:progressBarStyle"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_gravity="center" />

   <com.github.ksoichiro.android.observablescrollview.ObservableRecyclerView
        android:id="@+id/rv"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:visibility="gone" />

</FrameLayout>

score 3 · Accepted Answer · answered Feb 08 '16 at 19:20

You can use coordinatorlayout in your .xml file that contain toolBar , see below code:

   <LinearLayout
    xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    android:id="@+id/all"
    android:layout_height="match_parent"
    android:layout_width="wrap_content"
    android:orientation="vertical"
    android:fitsSystemWindows="true">
    <android.support.design.widget.CoordinatorLayout
        android:id="@+id/main_content"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        app:layout_scrollFlags="scroll|enterAlways"
        >

    <android.support.design.widget.AppBarLayout
        android:id="@+id/appBar"
        android:layout_width="match_parent"
        android:layout_height="wrap_content">
    <android.support.v7.widget.Toolbar
        android:id="@+id/toolbar"
        android:layout_height="?attr/actionBarSize"
        android:layout_width="match_parent"
        app:layout_scrollFlags="scroll|enterAlways"
        app:layout_collapseMode="pin"
        />
    </android.support.design.widget.AppBarLayout>

    <FrameLayout
        android:id="@+id/content_layout"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        app:layout_behavior="@string/appbar_scrolling_view_behavior"
        >
    </FrameLayout>

    </android.support.design.widget.CoordinatorLayout>
</LinearLayout>

Issued some problems, even the tabs are disappearing and the elevation of the toolbar is larger that the tabs. I added my xml files — Motassem Jalal, Feb 08 '16 at 20:37
add this attribute to ViewPager app:layout_behavior="@string/appbar_scrolling_view_behavior" — mahmoud moustafa, Feb 08 '16 at 20:43
Same result, no change. I want to animate the toolbar like the one in the WhatsApp — Motassem Jalal, Feb 08 '16 at 21:16
You don't add AppBarLayout as parent to ToolBar ,please review my code it's work fine for me like that in what'sApp — mahmoud moustafa, Feb 08 '16 at 21:27
It kind of worked, it is animating but the tabs are being displayed under the appBar, how can I display it under the appBar? — Motassem Jalal, Feb 09 '16 at 10:45

Hiding/Showing the action bar when scrolling

1 Answers1