FAB Behavior when showing CardView (Up & Down)

FAB Behavior when showing CardView (Up & Down) - android

I want to show a CardView as prompt like in Material Guidelines Specs:
https://www.google.com/design/spec/growth-communications/onboarding.html#onboarding-quickstart
Here is the link to the image:
Image
I've changed the behavior of the FAB Button like this and set to the .xml file:
public class FABBehavior extends FloatingActionButton.Behavior {
public FABBehavior(Context context, AttributeSet attr) {
super();
}
#Override
public boolean layoutDependsOn(CoordinatorLayout parent, FloatingActionButton child, View dependency) {
return dependency instanceof CardView;
}
#Override
public boolean onDependentViewChanged(CoordinatorLayout parent, FloatingActionButton child, View dependency) {
float translationY = Math.min(0, dependency.getTranslationY() - dependency.getHeight());
child.setTranslationY(translationY);
return true;
}
}
My .xml file look like this:
<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:layout_width="match_parent"
android:layout_height="match_parent"
android:fitsSystemWindows="true"
tools:context="com.nearme.client.activities.fragments.ScannerFragment">
<android.support.design.widget.AppBarLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:theme="#style/AppTheme.AppBarOverlay">
<android.support.v7.widget.Toolbar
android:id="#+id/toolbar"
android:layout_width="match_parent"
android:layout_height="?attr/actionBarSize"
android:background="?attr/colorPrimary"
android:title="#string/title_scanner"
app:popupTheme="#style/AppTheme.PopupOverlay" />
</android.support.design.widget.AppBarLayout>
<include layout="#layout/fragment_scanner_content" />
<android.support.v7.widget.CardView
android:id="#+id/cvBluetooth"
android:layout_width="match_parent"
android:layout_height="150dp"
android:animateLayoutChanges="true"
android:layout_gravity="bottom" >
<TextView
android:layout_width="match_parent"
android:layout_height="match_parent"
android:text="Prueba" />
</android.support.v7.widget.CardView>
<android.support.design.widget.FloatingActionButton
android:id="#+id/fab"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="right|bottom|end"
android:layout_margin="#dimen/fab_margin"
app:layout_behavior="com.nearme.client.utils.FABBehavior"
android:src="#android:drawable/ic_dialog_email" />
And the click listener of the FAB Button is this:
View.OnClickListener onClick = new View.OnClickListener() {
#Override
public void onClick(View v) {
if (v == fab) {
if (cardBluetooth.isShown()) {
cardBluetooth.setVisibility(View.GONE);
} else
cardBluetooth.setVisibility(View.VISIBLE);
}
}
};
The problem is when the CardView's visibility goes GONE the FAB button remain up in its position.
How can I update the position of the FAB when the CardView is GONE?
Even if I set the CardView in the CoordinatorLayout dinamically and remove it doesnt work.

Well, the problem was that onDependentViewChangedfrom FloatingActionButton.Behavior only get called when the dependent view have changed its position. But I only was changing its visibility so it didnt get called.
Now in the onClick I add to the view and remove it:
View.OnClickListener onClick = new View.OnClickListener() {
#Override
public void onClick(View v) {
if (v == fab) {
if (cardBluetooth.isShown()) {
coordinatorLayout.removeView(cardBluetooth);
} else
coordinatorLayout.addView(cardBluetooth);
}
}
};
And in FloatingActionButton.Behavior I added:
#Override
public void onDependentViewRemoved(CoordinatorLayout parent, FloatingActionButton child, View dependency) {
child.animate().translationY(0);
child.setTranslationY(0);
}
And this is the result:
GIF of result

Change the method layoutDependsOn method according to this:
#Override
public boolean layoutDependsOn(CoordinatorLayout parent, FloatingActionButton child, View dependency) {
return dependency instanceof CardView && onDependentViewChanged(parent, child, dependency);
}
Otherwise, the fab button is going to move up only the first time it gets clicked.

Related

How to hide bottom nav bar in fragment

I have bottom nav bar define in the Main activity. I have three fragments linked with BottomNavigation bar in fragments I have recycler view so I want to hide BottomNavigation bar when RecyclerView scrolls down and shows when RecyclerView scrolls up.
My problem is how can I access BottomNavigation bar in fragments because it is defined in MainActivity.
This is my code:
activity_main.xml
<?xml version="1.0" encoding="utf-8"?>
<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:layout_width="match_parent"
android:layout_height="match_parent"
tools:context=".MainActivity">
<android.support.design.widget.AppBarLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:theme="#style/AppTheme.AppBarOverlay"
app:elevation="0dp"
android:background="#color/colorPrimary"
android:paddingBottom="7dp"
android:fitsSystemWindows="true">
<android.support.v7.widget.Toolbar
android:id="#+id/toolbar"
android:layout_width="match_parent"
android:layout_height="?attr/actionBarSize"
android:background="?attr/colorPrimary"
app:popupTheme="#style/AppTheme.PopupOverlay"
app:layout_scrollFlags="scroll|enterAlways|snap">
<Spinner
android:layout_width="110dp"
android:layout_height="50dp"
android:id="#+id/chooseLocation"
app:backgroundTint="#android:color/white"/>
</android.support.v7.widget.Toolbar>
<EditText
android:layout_width="match_parent"
android:layout_height="40dp"
android:layout_marginLeft="16dp"
android:layout_marginRight="16dp"
android:id="#+id/search"
android:paddingTop="6dp"
android:paddingBottom="6dp"
android:paddingRight="6dp"
android:paddingLeft="12dp"
android:hint="Search here"
android:textColorHint="#9e9e9e"
android:textColor="#000"
tools:ignore="HardcodedText"
android:background="#drawable/search_edit_text"
android:paddingEnd="6dp"
android:paddingStart="12dp"/>
</android.support.design.widget.AppBarLayout>
<include layout="#layout/content_main" />
<android.support.design.widget.BottomNavigationView
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:id="#+id/bottomBar"
android:layout_gravity="bottom"
app:menu="#menu/bottom_menu"
android:background="#fff"
app:itemIconTint="#drawable/nav_check"
app:itemTextColor="#drawable/nav_check"/>
</android.support.design.widget.CoordinatorLayout>
fragment_home.xml
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout
xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context=".Tab1Fragment"
android:background="#fff">
<android.support.v7.widget.RecyclerView
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:id="#+id/purchasedBook"/>
</RelativeLayout>
This is how my fragments are defined as there is no bottom nav bar in any fragments so how can I access bottom nav bar in fragments.
Someone, please let me know any help would be appreciated.
THANKS

navController.addOnDestinationChangedListener { _, destination, _ ->
if(destination.id == R.id.full_screen_destination) {
bottomNavigationView.visibility = View.GONE
} else {
bottomNavigationView.visibility = View.VISIBLE
}
}
Do this in the main activity.
Here R.id.full_screen_destination is id of the fragment in navigation fragment.

To access your BottomNavigationView from within the fragments use the following code:
BottomNavigationView navBar = getActivity().findViewById(R.id.bottomBar);

As the fragment is always inside an activity and you can call getActivity() in fragment to access objects that already exist in the activity. So you can do this:
Activity
public class MainActivity extends Activity {
//...
Toolbar toolbar;
//...
public Toolbar getNav() {
return toolbar;
}
//...
}
Fragment
//...
if(getActivity() != null && getActivity instanceOf MainActivity)
((MainActivity)getActivity()).getNav().setVisiblity(View.GONE);
//...

Try this,
Add this line in the BottomNavigationView in Xml
app:layout_behavior="#string/hide_bottom_view_on_scroll_behavior"
And Implement this BottomNavigation behavior using CoOrdinator Layout and you can hide or show the view using the scroll listeners.
public class BottomNavigationViewBehavior extends CoordinatorLayout.Behavior<BottomNavigationView> {
private int height;
#Override
public boolean onLayoutChild(CoordinatorLayout parent, BottomNavigationView child, int layoutDirection) {
height = child.getHeight();
return super.onLayoutChild(parent, child, layoutDirection);
}
#Override
public boolean onStartNestedScroll(#NonNull CoordinatorLayout coordinatorLayout,
BottomNavigationView child, #NonNull
View directTargetChild, #NonNull View target,
int axes, int type)
{
return axes == ViewCompat.SCROLL_AXIS_VERTICAL;
}
#Override
public void onNestedScroll(#NonNull CoordinatorLayout coordinatorLayout, #NonNull BottomNavigationView child,
#NonNull View target, int dxConsumed, int dyConsumed,
int dxUnconsumed, int dyUnconsumed,
#ViewCompat.NestedScrollType int type)
{
if (dyConsumed > 0) {
slideDown(child);
} else if (dyConsumed < 0) {
slideUp(child);
}
}
private void slideUp(BottomNavigationView child) {
child.clearAnimation();
child.animate().translationY(0).setDuration(200);
}
private void slideDown(BottomNavigationView child) {
child.clearAnimation();
child.animate().translationY(height).setDuration(200);
}
}
Add this line code to your Activity where it contains bottom navigation
bottomNavigationView = (BottomNavigationView) findViewById(R.id.bottom_nav);
CoordinatorLayout.LayoutParams layoutParams = (CoordinatorLayout.LayoutParams)
bottomNavigationView .getLayoutParams();
layoutParams.setBehavior(new BottomNavigationViewBehavior());
Try this and let me know Digvijay.Happy Coding.

Fragment has onAttach() method which give you context. So you have to create instance of activity using,
MainActivity mainActivity;
#Override
public void onAttach(Context context) {
super.onAttach(context);
mainActivity = (MainActivity)context;
}
Now make method with boolean param which hide and show bottom bar.
public void visibilityOfBottom(boolean isScroll){
if(isScroll){
// hide bottom bar
} else{
// show bottom bar
}
}
Now access above method in fragment using MainActivity context by,
mainActivity.visibilityOfBottom(false);

Kotlin
Access the navigation view from a fragment
val navBar: BottomNavigationView = activity!!.findViewById(R.id.bottomBar)

The only way I found for hiding bottom navigator in V6
was making structure like this -
Stack Nav {
Bottom Nav
Screen 1
Screen 2
Screen 3
}

Add this code to your fragment. will hide the Bottom nav.
AppCompatActivity activity = (AppCompatActivity) view.getContext();
chipNavigationBar = activity.findViewById(R.id.chipNavigation);
chipNavigationBar.animate().translationY(chipNavigationBar.getHeight()).setDuration(1000);
Use this code :
when Scrolling down the Recyclerview to your fragment will hide the bottom navigation.
then when Scrolled Up it will show the Bottom nav.
private View view;
private AppCompatActivity activity;
private ChipNavigationBar chipNavigationBar;
//...............................................
#Override
public View onCreateView(#NonNull LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
if (view == null) {
view = inflater.inflate(R.layout.list_fragment, container, false);
hide_NavigationBar_adwhen_Scrolling();
}
return view;
}
//...........................................................
private void hide_NavigationBar_adwhen_Scrolling() {
activity = (AppCompatActivity) view.getContext();
chipNavigationBar = activity.findViewById(R.id.chipNavigation);
RecyclerView recyclerView = view.findViewById(R.id.recylerView);
recyclerView.addOnScrollListener(new RecyclerView.OnScrollListener() {
#Override
public void onScrolled(RecyclerView recyclerView, int dx, int dy) {
if (dy > 0) {//on_Scrolled_down
// chipNavigationBar.animate().translationY(200).setDuration(500);
chipNavigationBar.animate().translationY(banner_ad_card_1.getHeight()).setDuration(1000);
} else {//on_Scrolled_up
chipNavigationBar.setVisibility(View.VISIBLE);
chipNavigationBar.animate().translationY(0).setDuration(1000);
// chipNavigationBar.setItemSelected(R.id.home, true);
}
}
#Override
public void onScrollStateChanged(RecyclerView recyclerView, int newState) {
super.onScrollStateChanged(recyclerView, newState);
}
});
}

Add
app:layout_behavior="#string/hide_bottom_view_on_scroll_behavior"
to
BottomNavigationView
app:layout_behavior="#string/appbar_scrolling_view_behavior"
to
RecyclerView

Hide/Show bottomNavigationView on Scroll

I have to hide bottom navigation view on up scroll and show on down scroll .how to implement this?
my layout is like this
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
android:layout_width="match_parent"
android:layout_height="match_parent">
<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="vertical"
android:layout_above="#+id/navigation"
android:layout_alignParentTop="true"
android:layout_marginBottom="5dp">
<FrameLayout
android:id="#+id/container1"
android:layout_width="match_parent"
android:layout_height="wrap_content"
/>
</LinearLayout>
<android.support.design.widget.BottomNavigationView
android:id="#+id/navigation"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_alignParentBottom="true"
android:background="?android:attr/windowBackground"
app:layout_scrollFlags="scroll|enterAlways|snap"
app:menu="#menu/dashboard_slider_menu" />
</RelativeLayout>
I have attached screenshot of view. Kindly check it.

UPDATE
Just add one attribute to BottomNavigationView
Material Library AndroidX
<com.google.android.material.bottomnavigation.BottomNavigationView
....
app:layout_behavior="com.google.android.material.behavior.HideBottomViewOnScrollBehavior"/>
Support Library Version 28.0.0 or higher version
<android.support.design.widget.BottomNavigationView
....
app:layout_behavior="#string/hide_bottom_view_on_scroll_behavior"/>
Note:- Your XML should follow the structure of XML given below in old answer.
**OLD ANSWER(Still Works)**
You need a helper class to do this .This solution works like Google Material Design Guideline.
Create a class BottomNavigationViewBehavior
public class BottomNavigationViewBehavior extends CoordinatorLayout.Behavior<BottomNavigationView> {
private int height;
#Override
public boolean onLayoutChild(CoordinatorLayout parent, BottomNavigationView child, int layoutDirection) {
height = child.getHeight();
return super.onLayoutChild(parent, child, layoutDirection);
}
#Override
public boolean onStartNestedScroll(#NonNull CoordinatorLayout coordinatorLayout,
BottomNavigationView child, #NonNull
View directTargetChild, #NonNull View target,
int axes, int type)
{
return axes == ViewCompat.SCROLL_AXIS_VERTICAL;
}
#Override
public void onNestedScroll(#NonNull CoordinatorLayout coordinatorLayout, #NonNull BottomNavigationView child,
#NonNull View target, int dxConsumed, int dyConsumed,
int dxUnconsumed, int dyUnconsumed,
#ViewCompat.NestedScrollType int type)
{
if (dyConsumed > 0) {
slideDown(child);
} else if (dyConsumed < 0) {
slideUp(child);
}
}
private void slideUp(BottomNavigationView child) {
child.clearAnimation();
child.animate().translationY(0).setDuration(200);
}
private void slideDown(BottomNavigationView child) {
child.clearAnimation();
child.animate().translationY(height).setDuration(200);
}
}
For using this behavior you need to use cooradinator layout...
<android.support.v4.widget.DrawerLayout 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/drawer_layout"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context="com.kliff.digitaldwarka.activity.MainActivity">
<android.support.design.widget.CoordinatorLayout
android:id="#+id/coordinator_layout"
android:layout_width="match_parent"
android:layout_height="match_parent">
<android.support.design.widget.AppBarLayout
android:id="#+id/myAppBar"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:descendantFocusability="beforeDescendants"
android:focusableInTouchMode="true"
android:theme="#style/AppTheme.AppBarOverlay"
app:elevation="0dp">
<android.support.v7.widget.Toolbar
android:id="#+id/toolbar"
android:layout_width="match_parent"
android:layout_height="?attr/actionBarSize"
android:background="?attr/colorPrimary"
app:contentInsetStart="0dp"
app:layout_scrollFlags="scroll|enterAlways"
app:popupTheme="#style/AppTheme.PopupOverlay"/>
</android.support.design.widget.AppBarLayout>
<!---your RecyclerView/Fragment Container Layout-->
<FrameLayout
android:id="#+id/container"
android:layout_width="match_parent"
android:layout_height="match_parent"
app:layout_behavior="#string/appbar_scrolling_view_behavior" />
<android.support.design.widget.BottomNavigationView
android:id="#+id/bottom_nav"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_gravity="bottom"
app:itemBackground="#color/white"
app:menu="#menu/bottom_nav_menu" />
</android.support.design.widget.CoordinatorLayout>
<!---NavigationView-->
</android.support.v4.widget.DrawerLayout>
Add this code to your Activity that contains bottom nav..
mBottomNavigationView = (BottomNavigationView) findViewById(R.id.bottom_nav);
CoordinatorLayout.LayoutParams layoutParams = (CoordinatorLayout.LayoutParams) mBottomNavigationView.getLayoutParams();
layoutParams.setBehavior(new BottomNavigationViewBehavior());

Try this,
mRecyclerView.addOnScrollListener(new RecyclerView.OnScrollListener() {
#Override
public void onScrolled(RecyclerView recyclerView, int dx, int dy) {
if (dy > 0 && bottom_navigation.isShown()) {
bottom_navigation.setVisibility(View.GONE);
} else if (dy < 0 ) {
bottom_navigation.setVisibility(View.VISIBLE);
}
}
#Override
public void onScrollStateChanged(RecyclerView recyclerView, int newState) {
super.onScrollStateChanged(recyclerView, newState);
}
});
Image while scrolling up :-
Image while scrolling down:

Updated answer after the latest library updates:
Hiding the BottomNavigationView on scrolling is now available with just one flag in the layout! Starting from version 28.0.0-alpha1 or the material/androidX 1.0.0-alpha1.
I updated my project using the latter approach since the version now is a stable release candidate. Update: Use fully released version "1.0.0"!
The new out of the box available behaviour is called HideBottomViewOnScrollBehavior. Set it on the BottomNavigationView as
app:layout_behavior="#string/hide_bottom_view_on_scroll_behavior" as described in the latest docs.
Here is a full example:
<com.google.android.material.bottomnavigation.BottomNavigationView
android:id="#+id/navigation"
android:layout_width="match_parent"
android:layout_height="wrap_content"
app:labelVisibilityMode="selected"
app:layout_behavior="#string/hide_bottom_view_on_scroll_behavior"
android:layout_gravity="bottom"
app:layout_insetEdge="bottom"
app:menu="#menu/navigation" />
As with the hiding of the Toolbar on scrolling, you have to ensure that the content is a class that supports the latest scrolling like RecyclerView and NestedScrollView.
This ensures all is working as shown in the animation on the design specs
PS: labelVisibilityMode is another cool addition you get for free for taking the trouble of updating and that is described in depth in the design specs.

Update your project to Androidx i.e Refactor >> Migrate to androidx (Minimum Android studio version 3.4)
Using the default Bottom Navigation Menu xml file, replace the parent Constraint Layout with Coordinator layout.
Add the line app:layout_behavior="com.google.android.material.behavior.HideBottomViewOnScrollBehavior"
i.e
<?xml version="1.0" encoding="utf-8"?>
<androidx.coordinatorlayout.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/container"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context=".dashboards.Admin_dashboard_main">
<include layout="#layout/toolbar" />
<androidx.constraintlayout.widget.ConstraintLayout
android:id="#+id/main_area"
android:layout_width="match_parent"
android:layout_height="match_parent"
app:layout_constraintTop_toBottomOf="#+id/toolbar"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintLeft_toLeftOf="parent"
app:layout_constraintRight_toRightOf="parent"
android:layout_margin="0dp"
android:padding="0dp">
<!-- Fragments Container -->
<FrameLayout
android:layout_width="match_parent"
android:layout_height="match_parent"
app:layout_behavior="#string/appbar_scrolling_view_behavior"
tools:context="MainActivity"
tools:showIn="#layout/activity_tenant_dashboard"
android:id="#+id/fragment_container">
</FrameLayout>
</androidx.constraintlayout.widget.ConstraintLayout>
<!-- Bottom Navigation View -->
<com.google.android.material.bottomnavigation.BottomNavigationView
android:id="#+id/navigation"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_marginStart="0dp"
android:layout_marginEnd="0dp"
android:background="?android:attr/windowBackground"
android:layout_gravity="bottom"
app:menu="#menu/menu_admin_dashboard_main"
app:layout_behavior="com.google.android.material.behavior.HideBottomViewOnScrollBehavior"
/>
</androidx.coordinatorlayout.widget.CoordinatorLayout>

Use this
mRecyclerView.addOnScrollListener(new RecyclerView.OnScrollListener()
{
#Override
public void onScrolled(RecyclerView recyclerView, int dx, int dy)
{
if (dy > 0 ||dy<0 && csButtonLay.isShown())
{
bottomBar.setVisibility(View.GONE);
}
}
#Override
public void onScrollStateChanged(RecyclerView recyclerView, int newState)
{
if (newState == RecyclerView.SCROLL_STATE_IDLE)
{
bottomBar.setVisibility(View.VISIBLE);
}
super.onScrollStateChanged(recyclerView, newState);
}
});

Just use CoordinatorLayout as a parent container and add the app:layout_behavior
in the child View and set the behavior #string/hide_bottom_view_on_scroll_behavior
this is the solution.
<?xml version="1.0" encoding="utf-8"?>
<androidx.coordinatorlayout.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:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical"
tools:context=".Main2Activity">
<androidx.recyclerview.widget.RecyclerView
android:id="#+id/recyclerView"
android:layout_width="match_parent"
android:layout_above="#id/nav_view"
android:layout_height="wrap_content"
app:layoutManager="androidx.recyclerview.widget.LinearLayoutManager" />
<com.google.android.material.bottomnavigation.BottomNavigationView
android:id="#+id/nav_view"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_alignParentBottom="true"
android:layout_gravity="bottom"
app:layout_behavior="#string/hide_bottom_view_on_scroll_behavior"
android:background="?android:attr/windowBackground"
app:menu="#menu/bottom_nav_menu" />
</androidx.coordinatorlayout.widget.CoordinatorLayout>
Happy Coding.

I encountered this issue working with the Recyclerview.
The attribute:
app:layout_behavior="#string/hide_bottom_view_on_scroll_behavior"/>
only partially worked for me, so I had to implement another solution.
I defined the BottomNavigationView inside the MainActivity so I had to set a couple of methods to animate it during the scrolling.
class MainActivity : AppCompatActivity() {
private var animator: ObjectAnimator? = null
.
.
.
fun slideDown() {
nav_view?.let {
if (animator == null && it.translationY == 0f) {
animator = translationObjectY(it, 0f, it.height.toFloat() + it.marginBottom.toFloat()).apply {
doOnEnd {
animator = null
}
}
}
}
}
fun slideUp() {
nav_view?.let {
if (animator == null && it.translationY == it.height.toFloat() + it.marginBottom.toFloat()) {
animator = translationObjectY(it, it.height.toFloat() + it.marginBottom.toFloat(), 0f).apply {
doOnEnd {
animator = null
}
}
}
}
}
}
The translationObjectY is an extended function:
fun translationObjectY(
targetView: View?,
startY: Float,
endY: Float,
duration: Long = 200L
) : ObjectAnimator {
return ObjectAnimator.ofFloat(targetView, "translationY", startY, endY).apply {
this.duration = duration
interpolator = LinearOutSlowInInterpolator()
start()
}
}
And I finally create a custom Recyclerview:
class CustomRecyclerView(
context: Context,
attrs: AttributeSet?,
defStyle: Int,
) : RecyclerView(context, attrs, defStyle) {
constructor(context: Context)
: this(context, null, 0)
constructor(context: Context, attrs: AttributeSet)
: this(context, attrs, 0)
init {
this.addOnScrollListener(object : RecyclerView.OnScrollListener() {
override fun onScrolled(recyclerView: RecyclerView, dx: Int, dy: Int) {
if (dy > 0) {
// Scrolling up
hideBottomMenu()
} else {
// Scrolling down
showBottomMenu()
}
}
override fun onScrollStateChanged(recyclerView: RecyclerView, newState: Int) {
}
})
}
private fun hideBottomMenu() {
(context as? MainActivity)?.slideDown()
}
private fun showBottomMenu() {
(context as? MainActivity)?.slideUp()
}
}
You can then implement it in your fragment like this:
<com.studio.mattiaferigutti.kamasutra.custom.CustomRecyclerView
android:id="#+id/searchRecycler"
android:layout_width="match_parent"
android:layout_height="match_parent" />

Just simply add this in your xml
<BottomNavigationView
....
....
app:layout_behavior="#string/hide_bottom_view_on_scroll_behavior"/>

This can help somebody
read more:https://material.io/develop/android/components/app-bars-bottom
add
app:hideOnScroll="true"
inside BottomAppBar Like below:
<androidx.coordinatorlayout.widget.CoordinatorLayout
...>
...
<com.google.android.material.bottomappbar.BottomAppBar
...
app:hideOnScroll="true"
/>
...
</androidx.coordinatorlayout.widget.CoordinatorLayout>

Use this code : when Scrolling down the Recyclerview to your fragment will hide the bottom navigation. then when Scrolled Up it will show the Bottom nav.
private View view;
private AppCompatActivity activity;
private ChipNavigationBar chipNavigationBar;
//...............................................
#Override
public View onCreateView(#NonNull LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
if (view == null) {
view = inflater.inflate(R.layout.list_fragment, container, false);
hide_NavigationBar_adwhen_Scrolling();
}
return view;
}
//...........................................................
private void hide_NavigationBar_adwhen_Scrolling() {
activity = (AppCompatActivity) view.getContext();
chipNavigationBar = activity.findViewById(R.id.chipNavigation);
RecyclerView recyclerView = view.findViewById(R.id.recylerView);
recyclerView.addOnScrollListener(new RecyclerView.OnScrollListener() {
#Override
public void onScrolled(RecyclerView recyclerView, int dx, int dy) {
if (dy > 0) {//on_Scrolled_down
// chipNavigationBar.animate().translationY(200).setDuration(500);
chipNavigationBar.animate().translationY(banner_ad_card_1.getHeight()).setDuration(1000);
} else {//on_Scrolled_up
chipNavigationBar.setVisibility(View.VISIBLE);
chipNavigationBar.animate().translationY(0).setDuration(1000);
// chipNavigationBar.setItemSelected(R.id.home, true);
}
}
#Override
public void onScrollStateChanged(RecyclerView recyclerView, int newState) {
super.onScrollStateChanged(recyclerView, newState);
}
});
}

BottomSheetDialogFragment - Allow scrolling child

I have a BottomSheetDialogFragment with a RecyclerView. The problem is, I want to disable the drag close function of the BottomSheetDialogFragment as long as the RecyclerView is not scrolled up (currently I can't scroll my RecyclerView as the attempt will always close the BottomSheetDialogFragment). Any ideas how to achieve this?

RecyclerView scrolling problem in BottomSheetDialog can be solved by this way.
from: https://android.jlelse.eu/recyclerview-within-nestedscrollview-scrolling-issue-3180b5ad2542
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical">
<android.support.v4.widget.NestedScrollView
android:id="#+id/nestedScrollView"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:overScrollMode="never">
<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="vertical">
<android.support.v7.widget.RecyclerView
android:id="#+id/recyclerView"
android:layout_width="match_parent"
android:layout_height="wrap_content" />
</LinearLayout>
</android.support.v4.widget.NestedScrollView>
</LinearLayout>

Try this in your Fragment that extends RecyclerView in onCreateView
recyclerView.setOnTouchListener(new View.OnTouchListener() {
#Override
public boolean onTouch(View v, MotionEvent event) {
v.getParent().requestDisallowInterceptTouchEvent(true);
v.onTouchEvent(event);
return true;
}
});

Just add one (!) attribute to your layout:
<androidx.recyclerview.widget.RecyclerView
android:id="#+id/receiversList"
android:nestedScrollingEnabled="false"
android:layout_width="match_parent"
android:layout_height="match_parent"/>
android:nestedScrollingEnabled="false" doing all the job.
Also, if you wrap around your RecyclerView with SwipeRefreshLayout - refresh function will continue to work. And even you put your layout with more complex Views, your BottomSheetDialog will continue to support drag-down-to-dismiss behaviour (If touch with swipe down gesture occurs outside of RecyclerView & SwipeRefreshLayout).

Just treat it as a BottomSheetDialog , and simply disable its dragging or sliding when touch .
When create a BottomSheetDialog , it will automatically wrap your layout in a
CoordinatorLayout , so if you want to get a behaviour from your view , call
final BottomSheetBehavior behavior = BottomSheetBehavior.from((View) view.getParent());
Then through this behaviour, you can do what you need.
final BottomSheetBehavior behavior = BottomSheetBehavior.from((View) view.getParent());
behavior.setHideable(false);
behavior.setBottomSheetCallback(new BottomSheetBehavior.BottomSheetCallback() {
#Override
public void onStateChanged(#NonNull View bottomSheet, int newState) {
}
#Override
public void onSlide(#NonNull View bottomSheet, float slideOffset) {
behavior.setState(BottomSheetBehavior.STATE_EXPANDED);
}
});
This worked for me.Hope it helps.

When recycle view has scope to scroll, bottom sheet will remain expanded. But if recycle view has no scroll to up direction, than drag from up, will revert normal behaviour.
behavior.setState(BottomSheetBehavior.STATE_EXPANDED);
behavior.addBottomSheetCallback(new BottomSheetBehavior.BottomSheetCallback() {
#Override
public void onStateChanged(#NonNull View bottomSheet, int newState) {
if (newState == BottomSheetBehavior.STATE_HIDDEN) {
dismiss();
}
if (newState == BottomSheetBehavior.STATE_DRAGGING) {
if(!recyclerView.canScrollVertically(1)) {
behavior.setState(BottomSheetBehavior.STATE_EXPANDED);
}
}
}
#Override
public void onSlide(#NonNull View bottomSheet, float slideOffset) {
}
});

try this solution :
<androidx.core.widget.NestedScrollView
android:layout_width="match_parent"
android:layout_height="match_parent">
<LinearLayout
android:id="#+id/layout_form"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="vertical" >
<!-- elements-->
<!-- elements-->
</LinearLayout>
</androidx.core.widget.NestedScrollView>

Change the Behaviour in the BottomSheetDialogFragment in setupDialog method:
CoordinatorLayout.LayoutParams layoutParams = (CoordinatorLayout.LayoutParams) ((View) contentView.getParent()).getLayoutParams();
final CoordinatorLayout.Behavior behavior = layoutParams.getBehavior();
if (behavior != null && behavior instanceof BottomSheetBehavior) {
((BottomSheetBehavior) behavior).setBottomSheetCallback(new BottomSheetBehavior.BottomSheetCallback() {
#Override
public void onStateChanged(#NonNull View bottomSheet, int newState) {
if (newState == BottomSheetBehavior.STATE_HIDDEN) {
dismiss();
}
if (newState == BottomSheetBehavior.STATE_DRAGGING) {
((BottomSheetBehavior) behavior).setState(BottomSheetBehavior.STATE_EXPANDED);
}
}
#Override
public void onSlide(#NonNull View bottomSheet, float slideOffset) {
}
});
}

I had the same situation and what worked for me is just a single line of code inside onCreate function.
What you have to do is just enable recyclerViews nested scrolling.
recyclerView.setNestedScrollingEnabled(true);

I had the same problem recently on my project and I have tried all the answer suggested in this and in other threads on SO but without luck so I decided to solve it my way.
Just a note, my situation it's that I have a BottomSheetDialog with a complex layout that result in something like this
<LinearLayout
xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:id="_mainLayout"
android:orientation="vertical"
android:layout_width="match_parent"
android:layout_height="match_parent">
<View
android:id=" />
<LinearLayout
android:id="">
<ImageView
android:id=""/>
<LinearLayout
android:id="">
<TextView
android:id="" />
<TextView
android:id=""/>
</LinearLayout>
<LinearLayout
android:id="">
<TextView
android:id=""/>
</LinearLayout>
</LinearLayout>
<android.support.v7.widget.RecyclerView
android:layout_marginTop="10dp"
android:id=""
android:layout_width="match_parent"
android:layout_height="0dp"
android:layout_weight="1"/>
<Button
android:id="">
<Button
android:id="">
</LinearLayout>
Basically what it's needed it's to add a BottomSheetBehavior to the main layout of the dialog
_bottomSheetBehavior = BottomSheetBehavior.From((View)_mainLayout.Parent);
once we have this we create a custom BottomSheetCallback implementation and we add it to the behavior
_bottomSheetCallback = new BottomSheetFullScreenCallback(_bottomSheetBehavior);
_bottomSheetBehavior.AddBottomSheetCallback(_bottomSheetCallback);
last step it's to create a custo OntouchListener that we will add to the RecyclerView
_recyclerView.SetOnTouchListener(new MyTouchListener(_bottomSheetBehavior));
Now we have everything in place and we just need to manage the touch on the recyclerView. So in our custom OnTouchListener we implement the OnTouch method in this way
public bool OnTouch(View view, MotionEvent e)
{
if (e.Action == MotionEventActions.Down || e.Action == MotionEventActions.Move)
{
_bottomSheetBehavior.Draggable = false;
}
if (e.Action == MotionEventActions.Up)
{
_bottomSheetBehavior.Draggable = true;
}
return true;
}
Once we have done this we need to be sure that the OnSlide event of the custom BottomSheetCallback will never be called once the bottomSheetBehavior it's not draggable, and we can do this in the following way:
public override void OnSlide(View bottomSheet, float slideOffset)
{
if (_bottomSheetBehavior.Draggable)
{
OnSlideEvent?.Invoke(this, slideOffset);
}
}
And that's it ;)

To scroll RecyclerView inside BottomSheet can use this way:
Add android:focusableInTouchMode="true" to RecyclerView in file XML.
<androidx.recyclerview.widget.RecyclerView
android:id="#+id/recycler"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_marginTop="5dp"
android:clipToPadding="false"
android:focusableInTouchMode="true"
android:paddingBottom="50dp" />
- In func onCreateDialog for BottomSheet:
+ where: maxDesiredHeight is set fixed size of BottomSheet.
+ this.isDraggable = false -> disabling dragging on BottomSheet.
override fun onCreateDialog(savedInstanceState: Bundle?): Dialog {
val dialog = super.onCreateDialog(savedInstanceState) as BottomSheetDialog
dialog.setOnShowListener {
dialog.findViewById<FrameLayout>(com.google.android.material.R.id.design_bottom_sheet)!!
.apply {
val maxDesiredHeight = (resources.displayMetrics.heightPixels * 0.95).toInt()
val bottomSheetLayoutParams = this.layoutParams
bottomSheetLayoutParams.height = maxDesiredHeight
this.layoutParams = bottomSheetLayoutParams
BottomSheetBehavior.from(this).apply {
this.state = BottomSheetBehavior.STATE_EXPANDED
this.isDraggable = false
}
}
}
return dialog
}
- Call the setOnTouchListener function for RecyclerView:
Recycler.setOnTouchListener { v, event ->
v.parent.requestDisallowInterceptTouchEvent(true)
v.onTouchEvent(event)
true
}

With Constraint layout
<androidx.recyclerview.widget.RecyclerView
android:id="#+id/rv_team_mates"
android:layout_width="#dimen/dp_0"
android:layout_height="#dimen/dp_0"
android:layout_marginVertical="#dimen/dp_20"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toBottomOf="#id/txt_title_custom"
app:layout_constraintBottom_toBottomOf="parent"/>

Put your RecyclerView under NestedScrollView where NestedScroll is parent of recycler

CoordinatorLayout.Behavior not being called

I'm trying to implement coordinator layout behavior on a custom FAB menu as described here
The program compiles and runs but the coordinator layout behavior functions are never called so the SnackBar overlays the FAB menu.
The only other question on SO about it is here but the solution provided is not my issue.
Here is the xml:
<android.support.design.widget.CoordinatorLayout
xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent">
<com.getbase.floatingactionbutton.FloatingActionsMenu
android:id="#+id/fab_host"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="end|bottom"
android:layout_margin="#dimen/fab_margin"
app:layout_behavior="com.companionfree.quizinator.couple.shared.FloatingActionMenuBehavior"
fab:fab_icon="#drawable/ic_add_white_24dp"
fab:fab_addButtonColorNormal="#color/colorAccent">
<com.getbase.floatingactionbutton.FloatingActionButton
android:id="#+id/fab_host_bluetooth"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
fab:fab_colorNormal="#color/colorAccent"
fab:fab_icon="#drawable/ic_bluetooth_white_24dp"/>
<com.getbase.floatingactionbutton.FloatingActionButton
android:id="#+id/fab_host_nearby"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
fab:fab_colorNormal="#color/colorAccent"
fab:fab_icon="#drawable/ic_signal_wifi_4_bar_white_24dp"/>
</com.getbase.floatingactionbutton.FloatingActionsMenu>
</android.support.design.widget.CoordinatorLayout>
And here is my CoordinatorLayout.Behavior class:
public class FloatingActionMenuBehavior extends CoordinatorLayout.Behavior<FloatingActionsMenu> {
public FloatingActionMenuBehavior(Context context, AttributeSet attrs) {}
#Override
public boolean layoutDependsOn(CoordinatorLayout parent, FloatingActionsMenu child, View dependency) {
return dependency instanceof Snackbar.SnackbarLayout;
}
#Override
public boolean onDependentViewChanged(CoordinatorLayout parent, FloatingActionsMenu child, View dependency) {
float translationY = Math.min(0, dependency.getTranslationY() - dependency.getHeight());
child.setTranslationY(translationY);
return true;
}
}
There are no errors, the snackbar displays, it just overlays the FAB menu...I can't seem to figure out where the error is.

For the snack bar to push the FAB you need to pass the FloatingActionsMenu view to the snackBar while making it.
Snackbar.make(FloatingActionsMenuVIEWINSTANCEHERE, mErrorMessage, Snackbar.LENGTH_LONG);
and then call the show() method. This should fix the issue

Toolbar in AppBarLayout is scrollable although RecyclerView has not enough content to scroll

Is it really intended that the Toolbar in a AppBarLayout is scrollable although the main container with the "appbar_scrolling_view_behavior" has not enough content to really scroll?
What I have tested so far:
When I use a NestedScrollView (with "wrap_content" attribute) as main container and a TextView as child, the AppBarLayout works properly and does not scroll.
However, when I use a RecyclerView with only a few entries and the "wrap_content" attribute (so that there is no need to scroll), the Toolbar in the AppBarLayout is scrollable even though the RecyclerView never receives a scroll event (tested with a OnScrollChangeListener).
Here's my layout code:
<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/coordinatorLayout"
android:layout_width="match_parent"
android:layout_height="match_parent">
<android.support.design.widget.AppBarLayout
android:id="#+id/appBarLayout"
android:layout_width="match_parent"
android:layout_height="wrap_content">
<android.support.v7.widget.Toolbar
android:id="#+id/toolbar"
android:layout_width="match_parent"
android:layout_height="?attr/actionBarSize"
android:background="?attr/colorPrimary"
app:layout_scrollFlags="scroll|enterAlways"
app:theme="#style/ToolbarStyle" />
</android.support.design.widget.AppBarLayout>
<android.support.v7.widget.RecyclerView
android:id="#+id/recycler"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
app:layout_behavior="#string/appbar_scrolling_view_behavior" />
</android.support.design.widget.CoordinatorLayout>
With the following effect that the toolbar is scrollable although it's not necessary:
I've also found a way to deal with this by checking if all RecyclerView items are visible and using the setNestedScrollingEnabled() method of the RecyclerView.
Nevertheless, it does seem more like a bug as intended to me. Any opinions? :D
EDIT #1:
For people who are might be interested in my current solution, I had to put the setNestedScrollingEnabled() logic in the postDelayed() method of a Handler with 5 ms delay due to the LayoutManager which always returned -1 when calling the methods to find out whether the first and the last item is visible.
I use this code in the onStart() method (after my RecyclerView has been initialized) and every time after a content change of the RecyclerView occurs.
final LinearLayoutManager layoutManager = (LinearLayoutManager) mRecyclerView.getLayoutManager();
new Handler().postDelayed(new Runnable() {
#Override
public void run() {
//no items in the RecyclerView
if (mRecyclerView.getAdapter().getItemCount() == 0)
mRecyclerView.setNestedScrollingEnabled(false);
//if the first and the last item is visible
else if (layoutManager.findFirstCompletelyVisibleItemPosition() == 0
&& layoutManager.findLastCompletelyVisibleItemPosition() == mRecyclerView.getAdapter().getItemCount() - 1)
mRecyclerView.setNestedScrollingEnabled(false);
else
mRecyclerView.setNestedScrollingEnabled(true);
}
}, 5);
EDIT #2:
I just played around with a new app and it seems that this (unintended) behavior has been fixed in support library version 23.3.0 (or even earlier). Thus, there is no need for workarounds anymore!

Edit 2:
Turns out the only way to ensure Toolbar is not scrollable when RecyclerView is not scrollable is to set setScrollFlags programmatically which requires to check if RecyclerView's is scrollable. This check has to be done every time adapter is modified.
Interface to communicate with the Activity:
public interface LayoutController {
void enableScroll();
void disableScroll();
}
MainActivity:
public class MainActivity extends AppCompatActivity implements
LayoutController {
private CollapsingToolbarLayout collapsingToolbarLayout;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
setSupportActionBar(toolbar);
collapsingToolbarLayout =
(CollapsingToolbarLayout) findViewById(R.id.collapsing_toolbar);
final FragmentManager manager = getSupportFragmentManager();
final Fragment fragment = new CheeseListFragment();
manager.beginTransaction()
.replace(R.id.root_content, fragment)
.commit();
}
#Override
public void enableScroll() {
final AppBarLayout.LayoutParams params = (AppBarLayout.LayoutParams)
collapsingToolbarLayout.getLayoutParams();
params.setScrollFlags(
AppBarLayout.LayoutParams.SCROLL_FLAG_SCROLL
| AppBarLayout.LayoutParams.SCROLL_FLAG_ENTER_ALWAYS
);
collapsingToolbarLayout.setLayoutParams(params);
}
#Override
public void disableScroll() {
final AppBarLayout.LayoutParams params = (AppBarLayout.LayoutParams)
collapsingToolbarLayout.getLayoutParams();
params.setScrollFlags(0);
collapsingToolbarLayout.setLayoutParams(params);
}
}
activity_main.xml:
<android.support.v4.widget.DrawerLayout
xmlns:android="http://schemas.android.com/apk/res/android"
android:id="#+id/drawer_layout"
android:layout_height="match_parent"
android:layout_width="match_parent"
android:fitsSystemWindows="true">
<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/main_content"
android:layout_width="match_parent"
android:layout_height="match_parent">
<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.support.design.widget.CollapsingToolbarLayout
android:id="#+id/collapsing_toolbar"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:fitsSystemWindows="true"
app:contentScrim="?attr/colorPrimary">
<android.support.v7.widget.Toolbar
android:id="#+id/toolbar"
android:layout_width="match_parent"
android:layout_height="?attr/actionBarSize"
android:background="?attr/colorPrimary"
app:popupTheme="#style/ThemeOverlay.AppCompat.Light"/>
</android.support.design.widget.CollapsingToolbarLayout>
</android.support.design.widget.AppBarLayout>
<FrameLayout
android:id="#+id/root_content"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_gravity="fill_vertical"
app:layout_behavior="#string/appbar_scrolling_view_behavior"/>
</android.support.design.widget.CoordinatorLayout>
</android.support.v4.widget.DrawerLayout>
Test Fragment:
public class CheeseListFragment extends Fragment {
private static final int DOWN = 1;
private static final int UP = 0;
private LayoutController controller;
private RecyclerView rv;
#Override
public void onAttach(Context context) {
super.onAttach(context);
try {
controller = (MainActivity) getActivity();
} catch (ClassCastException e) {
throw new RuntimeException(getActivity().getLocalClassName()
+ "must implement controller.", e);
}
}
#Nullable
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
rv = (RecyclerView) inflater.inflate(
R.layout.fragment_cheese_list, container, false);
setupRecyclerView(rv);
// Find out if RecyclerView are scrollable, delay required
final Handler handler = new Handler();
handler.postDelayed(new Runnable() {
#Override
public void run() {
if (rv.canScrollVertically(DOWN) || rv.canScrollVertically(UP)) {
controller.enableScroll();
} else {
controller.disableScroll();
}
}
}, 100);
return rv;
}
private void setupRecyclerView(RecyclerView recyclerView) {
final LinearLayoutManager layoutManager = new LinearLayoutManager(recyclerView.getContext());
recyclerView.setLayoutManager(layoutManager);
final SimpleStringRecyclerViewAdapter adapter =
new SimpleStringRecyclerViewAdapter(
getActivity(),
// Test ToolBar scroll
getRandomList(/* with enough items to scroll */)
// Test ToolBar pin
getRandomList(/* with only 3 items*/)
);
recyclerView.setAdapter(adapter);
}
}
Sources:
Change scroll flags programmatically
Original code by Chris Banes
Need a postDelayed to ensure RecyclerView children are ready for calculations
Edit:
You should CollapsingToolbarLayout to control the behaviour.
Adding a Toolbar directly to an AppBarLayout gives you access to the enterAlwaysCollapsed and exitUntilCollapsed scroll flags, but not the detailed control on how different elements react to collapsing.
[...] setup uses CollapsingToolbarLayout’s app:layout_collapseMode="pin" to ensure that the Toolbar itself remains pinned to the top of the screen while the view collapses.http://android-developers.blogspot.com.tr/2015/05/android-design-support-library.html
<android.support.design.widget.CollapsingToolbarLayout
android:layout_width="match_parent"
android:layout_height="match_parent"
app:layout_scrollFlags="scroll|exitUntilCollapsed">
<android.support.v7.widget.Toolbar
android:id="#+id/drawer_toolbar"
android:layout_width="match_parent"
android:layout_height="?attr/actionBarSize"
app:layout_collapseMode="pin"/>
</android.support.design.widget.CollapsingToolbarLayout>
Add
app:layout_collapseMode="pin"
to your Toolbar in xml.
<android.support.v7.widget.Toolbar
android:id="#+id/toolbar"
android:layout_width="match_parent"
android:layout_height="?attr/actionBarSize"
android:background="?attr/colorPrimary"
app:layout_scrollFlags="scroll|enterAlways"
app:layout_collapseMode="pin"
app:theme="#style/ToolbarStyle" />

So, proper credit, this answer almost solved it for me https://stackoverflow.com/a/32923226/5050087. But since it was not showing the toolbar when you actually had an scrollable recyclerview and its last item was visible (it would not show the toolbar on the first scroll up), I decided to modify it and adapt it for an easier implementation and for dynamic adapters.
First, you must create a custom layout behavior for you appbar:
public class ToolbarBehavior extends AppBarLayout.Behavior{
private boolean scrollableRecyclerView = false;
private int count;
public ToolbarBehavior() {
}
public ToolbarBehavior(Context context, AttributeSet attrs) {
super(context, attrs);
}
#Override
public boolean onInterceptTouchEvent(CoordinatorLayout parent, AppBarLayout child, MotionEvent ev) {
return scrollableRecyclerView && super.onInterceptTouchEvent(parent, child, ev);
}
#Override
public boolean onStartNestedScroll(CoordinatorLayout parent, AppBarLayout child, View directTargetChild, View target, int nestedScrollAxes, int type) {
updatedScrollable(directTargetChild);
return scrollableRecyclerView && super.onStartNestedScroll(parent, child, directTargetChild, target, nestedScrollAxes, type);
}
#Override
public boolean onNestedFling(CoordinatorLayout coordinatorLayout, AppBarLayout child, View target, float velocityX, float velocityY, boolean consumed) {
return scrollableRecyclerView && super.onNestedFling(coordinatorLayout, child, target, velocityX, velocityY, consumed);
}
private void updatedScrollable(View directTargetChild) {
if (directTargetChild instanceof RecyclerView) {
RecyclerView recyclerView = (RecyclerView) directTargetChild;
RecyclerView.Adapter adapter = recyclerView.getAdapter();
if (adapter != null) {
if (adapter.getItemCount()!= count) {
scrollableRecyclerView = false;
count = adapter.getItemCount();
RecyclerView.LayoutManager layoutManager = recyclerView.getLayoutManager();
if (layoutManager != null) {
int lastVisibleItem = 0;
if (layoutManager instanceof LinearLayoutManager) {
LinearLayoutManager linearLayoutManager = (LinearLayoutManager) layoutManager;
lastVisibleItem = Math.abs(linearLayoutManager.findLastCompletelyVisibleItemPosition());
} else if (layoutManager instanceof StaggeredGridLayoutManager) {
StaggeredGridLayoutManager staggeredGridLayoutManager = (StaggeredGridLayoutManager) layoutManager;
int[] lastItems = staggeredGridLayoutManager.findLastCompletelyVisibleItemPositions(new int[staggeredGridLayoutManager.getSpanCount()]);
lastVisibleItem = Math.abs(lastItems[lastItems.length - 1]);
}
scrollableRecyclerView = lastVisibleItem < count - 1;
}
}
}
} else scrollableRecyclerView = true;
}
}
Then, you only need to define this behavior for you appbar in your layout file:
<android.support.design.widget.AppBarLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:fitsSystemWindows="true"
app:layout_behavior="com.yourappname.whateverdir.ToolbarBehavior"
>
I haven't tested it for screen rotation so let me know if it works like this. I guess it should work as I don't think the count variable is saved when the rotation happens, but let me know if it doesn't.
This was the easiest and cleanest implementation for me, enjoy it.

It is not a bug, all the events in a viewGroup are handled this way. Because your recyclerview is a child of coordinatorLayout so whenever the event is generated, it is first checked for parent and if parent is not interested only then it is passed down to child.
See google documentation

Something like this in a LayoutManager subclass seems to result in the desired behavior:
#Override
public boolean canScrollVertically() {
int firstCompletelyVisibleItemPosition = findFirstCompletelyVisibleItemPosition();
if (firstCompletelyVisibleItemPosition == RecyclerView.NO_POSITION) return false;
int lastCompletelyVisibleItemPosition = findLastCompletelyVisibleItemPosition();
if (lastCompletelyVisibleItemPosition == RecyclerView.NO_POSITION) return false;
if (firstCompletelyVisibleItemPosition == 0 &&
lastCompletelyVisibleItemPosition == getItemCount() - 1)
return false;
return super.canScrollVertically();
}
The documentation for canScrollVertically() says:
/**
* Query if vertical scrolling is currently supported. The default implementation
* returns false.
*
* #return True if this LayoutManager can scroll the current contents vertically
*/
Notice the wording of "can scroll the current contents vertically", which I believe implies that the current state should be reflected by the return value.
However, that is not done by any of the LayoutManager subclasses provided through the v7 recyclerview library (23.1.1), which makes me somewhat hesitant whether it is a correct solution; it might cause undesired effects in other situations than the one discussed in this question.

I've implemented it using my own Behavior class which might be attached to AppBarLayout:
public class CustomAppBarLayoutBehavior extends AppBarLayout.Behavior {
private RecyclerView recyclerView;
private int additionalHeight;
public CustomAppBarLayoutBehavior(RecyclerView recyclerView, int additionalHeight) {
this.recyclerView = recyclerView;
this.additionalHeight = additionalHeight;
}
public boolean isRecyclerViewScrollable(RecyclerView recyclerView) {
return recyclerView.computeHorizontalScrollRange() > recyclerView.getWidth() || recyclerView.computeVerticalScrollRange() > (recyclerView.getHeight() - additionalHeight);
}
#Override
public boolean onStartNestedScroll(CoordinatorLayout parent, AppBarLayout child, View directTargetChild, View target, int nestedScrollAxes) {
if (isRecyclerViewScrollable(mRecyclerView)) {
return super.onStartNestedScroll(parent, child, directTargetChild, target, nestedScrollAxes);
}
return false;
}
}
And below is the code how to set this behavior:
final View appBarLayout = ((DrawerActivity) getActivity()).getAppBarLayoutView();
CoordinatorLayout.LayoutParams layoutParams = (CoordinatorLayout.LayoutParams) appBarLayout.getLayoutParams();
layoutParams.setBehavior(new AppBarLayoutNoEmptyScrollBehavior(recyclerView, getResources().getDimensionPixelSize(R.dimen.control_bar_height)));

I suggested you try this sample that for support desing library elements.
this a layout like your layout in the sample.
<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/main_content"
android:layout_width="match_parent"
android:layout_height="match_parent">
<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.support.v7.widget.Toolbar
android:id="#+id/toolbar"
android:layout_width="match_parent"
android:layout_height="?attr/actionBarSize"
android:background="?attr/colorPrimary"
app:popupTheme="#style/ThemeOverlay.AppCompat.Light"
app:layout_scrollFlags="scroll|enterAlways" />
<android.support.design.widget.TabLayout
android:id="#+id/tabs"
android:layout_width="match_parent"
android:layout_height="wrap_content" />
</android.support.design.widget.AppBarLayout>
<android.support.v4.view.ViewPager
android:id="#+id/viewpager"
android:layout_width="match_parent"
android:layout_height="match_parent"
app:layout_behavior="#string/appbar_scrolling_view_behavior" />
</android.support.design.widget.CoordinatorLayout>

Thanks, I created a custom class of RecyclerView but the key is still using setNestedScrollingEnabled(). It worked fine on my side.
public class RecyclerViewCustom extends RecyclerView implements ViewTreeObserver.OnGlobalLayoutListener
{
public RecyclerViewCustom(Context context)
{
super(context);
}
public RecyclerViewCustom(Context context, #Nullable AttributeSet attrs)
{
super(context, attrs);
}
public RecyclerViewCustom(Context context, #Nullable AttributeSet attrs, int defStyle)
{
super(context, attrs, defStyle);
}
/**
* This supports scrolling when using RecyclerView with AppbarLayout
* Basically RecyclerView should not be scrollable when there's no data or the last item is visible
*
* Call this method after Adapter#updateData() get called
*/
public void addOnGlobalLayoutListener()
{
this.getViewTreeObserver().addOnGlobalLayoutListener(this);
}
#Override
public void onGlobalLayout()
{
// If the last item is visible or there's no data, the RecyclerView should not be scrollable
RecyclerView.LayoutManager layoutManager = getLayoutManager();
final RecyclerView.Adapter adapter = getAdapter();
if (adapter == null || adapter.getItemCount() <= 0 || layoutManager == null)
{
setNestedScrollingEnabled(false);
}
else
{
int lastVisibleItemPosition = ((LinearLayoutManager) layoutManager).findLastCompletelyVisibleItemPosition();
boolean isLastItemVisible = lastVisibleItemPosition == adapter.getItemCount() - 1;
setNestedScrollingEnabled(!isLastItemVisible);
}
unregisterGlobalLayoutListener();
}
private void unregisterGlobalLayoutListener()
{
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.JELLY_BEAN)
{
getViewTreeObserver().removeOnGlobalLayoutListener(this);
}
else
{
getViewTreeObserver().removeGlobalOnLayoutListener(this);
}
}
}

I would like to add a little to user3623735's answer. The following code is absolutely incorrect.
// Find out if RecyclerView are scrollable, delay required
final Handler handler = new Handler();
handler.postDelayed(new Runnable() {
#Override
public void run() {
if (rv.canScrollVertically(DOWN) || rv.canScrollVertically(UP)) {
controller.enableScroll();
} else {
controller.disableScroll();
}
}
}, 100);
And even when it works - it doesn't cover all cases. There is absolutely no guarantee that a data will be displayed in 100 ms, and the data can stretch the height of the view in the process of working with it, not only in the onCreateView method. That's why you should use next code and track changes in view height:
view.addOnLayoutChangeListener(new View.OnLayoutChangeListener() {
#Override
public void onLayoutChange(View v, int left, int top, int right, int bottom, int oldLeft, int oldTop, int oldRight, int oldBottom) {
if(bottom != oldBottom)
{
mActivity.setScrollEnabled(view.canScrollVertically(0) || view.canScrollVertically(1));
}
}
});
Moreover no need to create two separated method to control scrolling status, you should use one setScrollEnabled method:
public void setScrollEnabled(boolean enabled) {
final AppBarLayout.LayoutParams params = (AppBarLayout.LayoutParams)
mToolbar.getLayoutParams();
params.setScrollFlags(enabled ?
AppBarLayout.LayoutParams.SCROLL_FLAG_SCROLL | AppBarLayout.LayoutParams.SCROLL_FLAG_ENTER_ALWAYS : 0);
mToolbar.setLayoutParams(params);
}

In your Toolbar remove the scroll flag, leaving only the enterAlways flag and you should get the effect you intended. For completeness, your layout should look like:
<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/coordinatorLayout"
android:layout_width="match_parent"
android:layout_height="match_parent">
<android.support.design.widget.AppBarLayout
android:id="#+id/appBarLayout"
android:layout_width="match_parent"
android:layout_height="wrap_content">
<android.support.v7.widget.Toolbar
android:id="#+id/toolbar"
android:layout_width="match_parent"
android:layout_height="?attr/actionBarSize"
android:background="?attr/colorPrimary"
app:layout_scrollFlags="enterAlways"
app:theme="#style/ToolbarStyle" />
</android.support.design.widget.AppBarLayout>
<android.support.v7.widget.RecyclerView
android:id="#+id/recycler"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
app:layout_behavior="#string/appbar_scrolling_view_behavior" />
</android.support.design.widget.CoordinatorLayout>

Develop Reference

The Android operating system is a mobile operating system that was developed by Google (GOOGL?) to be primarily used for touchscreen devices, cell phones, and tablets.

FAB Behavior when showing CardView (Up & Down) - android

Related

How to hide bottom nav bar in fragment

Hide/Show bottomNavigationView on Scroll

BottomSheetDialogFragment - Allow scrolling child

CoordinatorLayout.Behavior not being called

Toolbar in AppBarLayout is scrollable although RecyclerView has not enough content to scroll

Categories

Resources