I'm trying to use a CoordinatorLayout with a BottomNavigationView, an AppBarLayout, and a ViewPager. Here is my layout:
<?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"
android:fitsSystemWindows="true"
tools:context=".MainActivity">
<android.support.design.widget.AppBarLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:fitsSystemWindows="true"
android:theme="#style/AppTheme.AppBarOverlay">
<android.support.v7.widget.Toolbar
android:id="#+id/toolbar"
android:layout_width="match_parent"
android:layout_height="?attr/actionBarSize"
app:layout_scrollFlags="enterAlways|scroll"
app:popupTheme="#style/AppTheme.PopupOverlay"/>
</android.support.design.widget.AppBarLayout>
<android.support.v4.view.ViewPager
android:id="#+id/pager"
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/navigation"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_gravity="bottom"
android:background="?android:attr/windowBackground"
app:itemIconTint="?colorPrimaryDark"
app:itemTextColor="?colorPrimaryDark"
app:menu="#menu/navigation"/>
</android.support.design.widget.CoordinatorLayout>
The problem is that the CoordinatorLayout places the ViewPager to extend to the bottom of the screen, so the bottom is obscured by the BottomNavigationView, like this:
This happens even though the CoordinatorLayout itself doesn't extend down so far:
I've tried adding app:layout_insetEdge="bottom" to the BottomNavigationView and app:layout_dodgeInsetEdges="bottom" to the ViewPager, but that has a different problem: it shifts the bottom of the ViewPager up, but it keeps the same height, so the top is now chopped off:
I tried two other experiments. First, I tried removing the BottomNavigationView from the CoordinatorLayout and making them siblings under a vertical LinearLayout. Second, I put the ViewPager and BottomNavigationView together under a LinearLayout, hoping they would layout out correctly. Neither helped: in the first case, the CoordinatorLayout still sized the ViewPager with respect to the entire screen, either hiding part of it behind the BottomNavigationView or chopping off the top. In the second case, the user needs to scroll to see the BottomNavigationView.
How do I get the layout right?
P.S. When I tried the layout suggested by #Anoop S S (putting the CoordinatorLayout and the BottomNavigationView as siblings under a RelativeLayout), I get the following (with the ViewPager still extending down behind the BottomNavigationView):
As before, the CoordinatorView itself only extends down to the top of the BottomNavigationView.
I came up with a different approach (not battle tested yet though):
I subclassed AppBarLayout.ScrollingViewBehavior to adjust the bottom margin of the content view based on the height of the BottomNavigationView (if present). This way it should be future proof (hopefully) if the height of the BottomNavigationView changes for any reason.
The subclass (Kotlin):
class ScrollingViewWithBottomNavigationBehavior(context: Context, attrs: AttributeSet) : AppBarLayout.ScrollingViewBehavior(context, attrs) {
// We add a bottom margin to avoid the bottom navigation bar
private var bottomMargin = 0
override fun layoutDependsOn(parent: CoordinatorLayout, child: View, dependency: View): Boolean {
return super.layoutDependsOn(parent, child, dependency) || dependency is BottomNavigationView
}
override fun onDependentViewChanged(parent: CoordinatorLayout, child: View, dependency: View): Boolean {
val result = super.onDependentViewChanged(parent, child, dependency)
if(dependency is BottomNavigationView && dependency.height != bottomMargin) {
bottomMargin = dependency.height
val layout = child.layoutParams as CoordinatorLayout.LayoutParams
layout.bottomMargin = bottomMargin
child.requestLayout()
return true
} else {
return result
}
}
}
And then in the layout XML you put:
app:layout_behavior=".ScrollingViewWithBottomNavigationBehavior"
instead of
app:layout_behavior="#string/appbar_scrolling_view_behavior"
Basically what you have to do is create a Relativelayout as parent and put BottomNavigationView and CoordinatorLayout as children. Then align BottomNavigationView at the bottom and set CoordinatorLayout above that. Please try the below code. It might have few attribute erros, because I wrote it here itself. And sorry for the messed up indentation.
<?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"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context=".MainActivity">
<android.support.design.widget.CoordinatorLayout
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_above="#+id/navigation"
>
<android.support.design.widget.AppBarLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:fitsSystemWindows="true"
android:theme="#style/AppTheme.AppBarOverlay">
<android.support.v7.widget.Toolbar
android:id="#+id/toolbar"
android:layout_width="match_parent"
android:layout_height="?attr/actionBarSize"
app:layout_scrollFlags="enterAlways|scroll"
app:popupTheme="#style/AppTheme.PopupOverlay"/>
</android.support.design.widget.AppBarLayout>
<android.support.v4.view.ViewPager
android:id="#+id/pager"
android:layout_width="match_parent"
android:layout_height="match_parent"
app:layout_behavior="#string/appbar_scrolling_view_behavior"/>
</android.support.design.widget.CoordinatorLayout>
<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:itemIconTint="?colorPrimaryDark"
app:itemTextColor="?colorPrimaryDark"
app:menu="#menu/navigation"/>
</RelativeLayout>
This is caused by app:layout_behavior="#string/appbar_scrolling_view_behavior" in your ViewPager. If you remove this line, you will see now it fits the CoordinatorLayout container (unfortunately, this includes now being underneath the Toolbar).
I found it helped to treat CoordinatorLayout as just a FrameLayout, with a few extra tricks. The app:layout_behavior attribute above is necessary to allow the toolbar to appear to scroll in and out... in reality, the layout is doing this by having the view linked to the collapsing toolbar (in your case, your ViewPager) be exactly a toolbar's height larger than the bounds. Scrolling up brings the view up to the bottom within the bounds, and pushes the toolbar up extending beyond the bounds. Scrolling down, vice versa.
Now, onto the BottomNavigationView! If, as I did, you want the BottomNavigationView visible the whole time, then move it outside the CoordinatorLayout, as Anoop said. Use CoordinatorLayout only for things that need to coordinate, everything else outside. I happened to use a ConstraintLayout for my parent view (you could use RelativeLayout or whatever works for you though). With ConstraintLayout, for you it would look like this:
<android.support.constraint.ConstraintLayout
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">
<android.support.design.widget.CoordinatorLayout
android:layout_width="0dp"
android:layout_height="0dp"
app:layout_constraintBottom_toTopOf="#id/navigation"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="parent"
tools:context=".MainActivity">
<android.support.design.widget.AppBarLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:fitsSystemWindows="true"
android:theme="#style/AppTheme.AppBarOverlay">
<android.support.v7.widget.Toolbar
android:id="#+id/toolbar"
android:layout_width="match_parent"
android:layout_height="?attr/actionBarSize"
app:layout_scrollFlags="enterAlways|scroll"
app:popupTheme="#style/AppTheme.PopupOverlay" />
</android.support.design.widget.AppBarLayout>
<android.support.v4.view.ViewPager
android:id="#+id/pager"
android:layout_width="match_parent"
android:layout_height="match_parent"
app:layout_behavior="#string/appbar_scrolling_view_behavior" />
</android.support.design.widget.CoordinatorLayout>
<android.support.design.widget.BottomNavigationView
android:id="#+id/navigation"
android:layout_width="0dp"
android:layout_height="wrap_content"
android:background="?android:attr/windowBackground"
app:itemIconTint="?colorPrimaryDark"
app:itemTextColor="?colorPrimaryDark"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:menu="#menu/navigation" />
</android.support.constraint.ConstraintLayout>
In Android Studio design view, you're still going to see the ViewPager appear to be larger than the container (probably looks like it's behind the Bottom Nav still). But that's ok, when you get to the bottom of the ViewPager's content, it will show (i.e. won't be behind the bottom navigation). This quirk in the design view is just the way the CoordinatorLayout makes the toolbar show/hide, as mentioned earlier.
I had a similar problem with a layout very close to OP's and a ViewPager with 3 pages but only page 2 and 3 which should be affected by appbar_scrolling_view_behavior.
After struggling for hours exploring dead-end possible solutions (layout_dodgeInsetEdges, Window insets, attempting to modify ViewPager's page measured size, android:clipChildren, fitSystemWindows, ...), I finally found an easy solution detailed below.
As Vin Norman explained, ViewPager overlapping BottomNavigation is entirely caused by appbar_scrolling_view_behavior set on the ViewPager. AppBarLayout will just make fullscreen the sibling that has appbar_scrolling_view_behavior. That's how it works.
If you only need this behavior on certain ViewPager pages, there is a simple fix than you can apply on the ViewPager's OnPageChangeListener to dynamically change the Behavior and add/remove required padding:
public class MyOnPageChangeListener extends ViewPager.SimpleOnPageChangeListener {
#Override
public void onPageSelected(int position) {
...
CoordinatorLayout.LayoutParams params = (CoordinatorLayout.LayoutParams) _viewPager.getLayoutParams();
if(position == 0) {
params.setBehavior(null);
params.setMargins(params.leftMargin, _appBarLayoutViewPagerMarginTopPx,
params.rightMargin, _appBarLayoutViewPagerMarginBottomPx);
} else {
params.setBehavior(_appBarLayoutViewPagerBehavior);
params.setMargins(params.leftMargin, 0, params.rightMargin, 0);
}
_viewPager.requestLayout();
}
}
For page at position 0 (the one we want the ViewPager to extend exactly below the Toolbar and above the BottomNavigationView), it removes the behavior and adds top and bottom padding, respectively _appBarLayoutViewPagerMarginTopPx and _appBarLayoutViewPagerMarginBottomPx that are constants easy to compute beforehand (respectively the value in pixel for R.attr.actionbarSize and the height for the NavigationBottomView. Usually both are 56dp)
For all other pages needing appbar_scrolling_view_behavior we restore the associated scrolling behavior (stored beforehand in _appBarLayoutViewPagerBehavior) and remove top and bottom padding.
I tested this solution and it works fine without caveat.
In case anyone is still searching for a solution of this problem:
Cause of the problem is that CoordinatorLayout is not calculating correctly size of AppBarLayout because it has Toolbar with app:layout_scrollFlags="enterAlways|scroll" setting. It thinks that Toolbar will hide when scrolling so it leaves all available space to ViewPager, but actually what happens is that toolbar shows so ViewPager moves down, behind NavigationBar.
Easiest way to solve this is just to add android:minHeight="?attr/actionBarSize" (or whatever toolbar height you are using) to AppBarLayout. This way CoordinatorLayout will know properly how much space it needs to leave for ViewPager.
If it still matters to someone:
In the answer of Anoop SS above, trying replacing the RelativeLayout with LinearLayout. Also set layout_height of CoordinatorLayout to 0dp and set layout_weight to 1.
I had almost the same problem....just that i wanted to have a static AdView at the bottom instead of the BottomNavigationView. Trying Anoop SS suggestions, at first, I got the same behaviour as OP: ViewPager extended behind the AdView. But then I did what I suggested about and everything worked fine.
Android layouts behave in weird manner or may be it is the lack of good documentation or the lack of knowledge on our part....but making a layout is just too annoying most of the time.
If you are using Androidx try this
<RelativeLayout 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=".MainActivity">
<androidx.coordinatorlayout.widget.CoordinatorLayout
android:layout_width="match_parent"
android:layout_height="match_parent"
android:fitsSystemWindows="true"
android:layout_above="#+id/bottomNavView">
<com.google.android.material.appbar.AppBarLayout
android:id="#+id/appBarLayout"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:theme="#style/AppTheme.AppBarOverlay">
<androidx.appcompat.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:popupTheme="#style/AppTheme.PopupOverlay" />
</com.google.android.material.appbar.AppBarLayout>
<FrameLayout
android:layout_width="match_parent"
android:layout_height="match_parent"
app:layout_behavior="#string/appbar_scrolling_view_behavior">
<fragment
android:id="#+id/nav_host_fragment"
android:name="androidx.navigation.fragment.NavHostFragment"
android:layout_width="match_parent"
android:layout_height="match_parent"
app:defaultNavHost="true"
app:navGraph="#navigation/mobile_navigation" />
</FrameLayout>
</androidx.coordinatorlayout.widget.CoordinatorLayout>
<com.google.android.material.bottomnavigation.BottomNavigationView
android:id="#+id/bottomNavView"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_alignParentBottom="true"
android:background="?android:attr/windowBackground"
app:menu="#menu/bottom_nav" />
Related
I have an AppBarLayout in my app along with a FrameLayout that I use as a placeholder to load in fragments:
<android.support.design.widget.AppBarLayout
android:layout_height="wrap_content"
android:layout_width="match_parent"
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"
app:popupTheme="#style/AppTheme.PopupOverlay"/>
<FrameLayout android:id="#+id/main_content_fragment"
android:layout_height="wrap_content"
android:layout_width="match_parent"
android:background="#color/white" />
</android.support.design.widget.AppBarLayout>
The fragment in question looks like this:
<LinearLayout
xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
android:orientation="vertical"
android:layout_width="match_parent"
android:layout_height="match_parent">
<ProgressBar android:id="#+id/loading_downloaded"
android:layout_width="wrap_content"
android:layout_height="wrap_content" />
<android.support.v7.widget.RecyclerView
android:id = "#+id/items_downloaded"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:scrollbars="vertical"
app:layout_constraintEnd_toEndOf="parent"
/>
</LinearLayout>
The Fragment is substituted in from code as you might anticipate:
val fragMan: FragmentManager = getSupportFragmentManager()
fragMan.beginTransaction().add(R.id.main_content_fragment, fragment).commit()
The problem is that I cannot scroll my RecyclerView when I format it this way. If I move the FrameLayout outside of the AppBarLayout it works perfectly but then the fragment lies behind the app bar, which is very untidy. This confirms for me that the fragment is working correctly, I just can't figure out why the fragment's scroll behaviour changes when it's within the AppBarLayout.
What do I need to do to be able to scroll my content? Or have I misunderstood and I need to display my fragments outside the AppBarLayout where they scroll correctly and shift everything down by the height of the app bar?
Your fragment's content is meant to be placed as a sibling of the AppBarLayout. You should wrap everything inside a CoordinatorLayout and set this attribute in your FrameLayout where your fragment resides: app:layout_behavior="#string/appbar_scrolling_view_behavior".
Here's your XML structure would be:
<CoordinatorLayout>
<FrameLayout
app:layout_behavior="#string/appbar_scrolling_view_behavior" ... >
...
</FrameLayout>
<AppBarLayout> ... </AppBarLayout>
</CoordinatorLayout>
Having this setup would allow your fragment to show all of it's views with your AppBarLayout. CoordinatorLayout will take care of everything for you.
Here's the official documentation:
AppBarLayout also requires a separate scrolling sibling in order to
know when to scroll. The binding is done through the
AppBarLayout.ScrollingViewBehavior behavior class, meaning that you
should set your scrolling view's behavior to be an instance of
AppBarLayout.ScrollingViewBehavior. A string resource containing the
full class name is available.
See this link for more details: https://developer.android.com/reference/android/support/design/widget/AppBarLayout.html
I'm setting up the app navigation with the new Jetpack Navigation Component and the NavigationUI class to support navigation within a CollapsingToolbarLayout.
However it does not work using the code/method from the documentation.
I've setted up the MainActivity as shown in the documentation:
LinearLayout as Parent View, within an AppBarLayout, within a CollapsingToolbarLayout, and the toolbar itself. And the host fragment.
The navigation start destination is a FrameLayout, which contains the actual RecyclerView.
I tried various layout_scrollFlags and tried to set a CoordinatorLayout as parent view instead of a LinearLayout.
activity_main.xml
<LinearLayout
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent" android:layout_height="match_parent"
android:orientation="vertical">
<com.google.android.material.appbar.AppBarLayout
android:layout_width="match_parent"
android:layout_height="wrap_content">
<com.google.android.material.appbar.CollapsingToolbarLayout
android:id="#+id/collapsing_toolbar_layout"
android:layout_width="match_parent"
android:layout_height="match_parent"
app:contentScrim="?attr/colorPrimary"
app:expandedTitleGravity="top"
app:layout_scrollFlags="scroll|exitUntilCollapsed|snap">
<androidx.appcompat.widget.Toolbar
android:id="#+id/toolbar"
android:layout_width="match_parent"
android:layout_height="?attr/actionBarSize"
android:background="?attr/colorPrimary"
android:theme="#style/ThemeOverlay.AppCompat.Dark.ActionBar"
app:popupTheme="#style/ThemeOverlay.AppCompat.Light"
app:layout_collapseMode="pin"/>
</com.google.android.material.appbar.CollapsingToolbarLayout>
</com.google.android.material.appbar.AppBarLayout>
<fragment
android:id="#+id/nav_host_fragment"
android:name="androidx.navigation.fragment.NavHostFragment"
android:layout_width="match_parent"
android:layout_height="match_parent"
app:defaultNavHost="true"
app:navGraph="#navigation/nav_graph"/>
</LinearLayout>
In the MainActivity onCreate function:
// Set Toolbar as ActionBar
setSupportActionBar(findViewById(R.id.toolbar))
val layout = findViewById<CollapsingToolbarLayout>(R.id.collapsing_toolbar_layout)
val toolbar = findViewById<Toolbar>(R.id.toolbar)
val navController = findNavController(R.id.nav_host_fragment)
val appBarConfiguration = AppBarConfiguration(navController.graph)
layout.setupWithNavController(toolbar, navController, appBarConfiguration)
The first destination where I expect the collapsing behaviour:
<FrameLayout 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" xmlns:app="http://schemas.android.com/apk/res-auto"
tools:context=".restaurant.RestaurantsFragment">
<androidx.recyclerview.widget.RecyclerView
android:id="#+id/restaurant_recyclerview"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:listitem="#layout/restaurant_item"/>
</FrameLayout>
I expect the toolbar collapsing while scrolling through the RecyclerView.
Actual it's just static.
I think there might be a connection between the RecyclerView and the CollapsingToolbar missing?
What am I missing?
Thank you, you are my saviour. I've also struggled with this recently, so I've played around with your solution a bit more, and I've come to a few
conclusions (time of writing 2019-08-08):
TL;DR CollapsingToolbarLayout works too, but fragment is sized incorrectly.
The top level layout must be a CoordinatorLayout, because if it wasn't nothing could coordinate the AppBarLayout and the fragment.
The <fragment> element must have the attribute app:layout_behavior="#string/appbar_scrolling_view_behavior". It seems that CoordinatorLayout only searches among its direct children to find a behavior.
It's actually fine to have a AppBarLayout/CollapsingToolbarLayout/Toolbar hierarchy. As long as the <fragment> has app:layout_behavior attribute, this will
also work fine.
The layout inside the fragment doesn't really matter. In my case use a viewmodel which means I need an extra <layout> wrapper so I've tried both
<layout>
<data></data>
<FrameLayout>
<RecyclerView/>
<FrameLayout>
</layout>
and
<layout>
<data></data>
<CoordinatorLayout>
<RecyclerView/>
<CoordinatorLayout>
</layout>
which both work fine. The inner CoordinatorLayout doesn't swallow the behavior because the RecyclerView doesn't have or use a behavior, but this leads me to my next point:
This arrangement doesn't resize the fragment properly. If you also add a FloatingActionButton to the fragment, it doesn't work with FrameLayout properly (FAB in upper left corner despite app:layout_anchorGravity="bottom|right|end").
If you use a CoordinatorLayout inside the fragment, like in my second example above, the FAB jumps to the right position. Showing and hiding doesn't work, even if you implement yourself a ScrollAwareFABBehavior. Instead what happens is that the FAB scrolls offscreen, showing that the fragment is 100% the vertical height of the viewport, but gets shifted down by the height of the toolbar (if it's an expanded CollapsingToolbarLayout, this could be 300dp or almost half the screen in my case).
I haven't been able to find a way around this problem and I'm going to stop trying for the time being. It seems that the single-activity/single-toolbar model isn't able to handle CoordinatorLayout things just yet. The reason the Android docs use a LinearLayout is probably to make sure the fragment has the correct vertical size, but the give up any dynamic behavior features along the way. I will probably be using nested navigation graphs going forward where each section of the app will have the appropriate toolbar contained within it.
If anyone has any suggestions or pointers, please do comment. I'd like to actually get this working some day.
Found a solution.
Use CoordinatorLayout as Parent View instead of LinearLayout.
Remove the CollapsingToolbarLayout.
Declare layout_scrollFlags in the Toolbar (eg. app:layout_scrollFlags="scroll|enterAlways|snap").
And in the fragment View add app:layout_behavior="#string/appbar_scrolling_view_behavior" (important since we use a RecyclerView in the home Fragment)
main_activity.xml
<androidx.coordinatorlayout.widget.CoordinatorLayout
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent" android:layout_height="match_parent"
android:orientation="vertical">
<com.google.android.material.appbar.AppBarLayout
android:layout_width="match_parent"
android:layout_height="wrap_content">
<androidx.appcompat.widget.Toolbar
android:id="#+id/toolbar"
android:layout_width="match_parent"
android:layout_height="?attr/actionBarSize"
android:background="?attr/colorPrimary"
android:theme="#style/ThemeOverlay.AppCompat.Dark.ActionBar"
app:popupTheme="#style/ThemeOverlay.AppCompat.Light"
app:layout_scrollFlags="scroll|enterAlways|snap"
/>
</com.google.android.material.appbar.AppBarLayout>
<fragment
android:id="#+id/nav_host_fragment"
android:name="androidx.navigation.fragment.NavHostFragment"
android:layout_width="match_parent"
android:layout_height="match_parent"
app:defaultNavHost="true"
app:navGraph="#navigation/nav_graph"
app:layout_behavior="#string/appbar_scrolling_view_behavior"/>
</androidx.coordinatorlayout.widget.CoordinatorLayout>
MainActivity onCreate
// Set Toolbar as ActionBar
setSupportActionBar(findViewById(R.id.toolbar))
val navController = findNavController(R.id.nav_host_fragment)
val appBarConfiguration = AppBarConfiguration(navController.graph)
findViewById<Toolbar>(R.id.toolbar)
.setupWithNavController(navController, appBarConfiguration)
I'm trying to obtain this effect where if the user scroll a RecyclerView a certain layout scroll up together with the recycler and disappear behind a Toolbar.
A similar behavior could be obtained using the CoordinatorLayout, this would be possible by setting
app:layout_behavior="#string/appbar_scrolling_view_behavior"
on the said Recycler, and doing
<android.support.design.widget.AppBarLayout
android:layout_width="match_parent"
android:layout_height="wrap_content">
<android.support.v7.widget.Toolbar
android:layout_width="match_parent"
android:layout_height="?attr/actionBarSize"
app:layout_scrollFlags="scroll|enterAlways"/>
</android.support.design.widget.AppBarLayout>
Also, If I put a second child inside the AppBarLayout, and set app:layout_scrollFlags to it, the effect obtained is the same, with both layout scrolling together with the Recycler.
What I'm trying to achieve is to keep the first child (The toolbar) fixed in position, and let the second child (a LinearLayout) to scroll and hide behind the toolbar. Unfortunately I couldn't get to this behavior.
Is it possible without using 3rd part library?
Thanks in advance and sorry for my english.
Finally I figured out a way to achieve this behavior, by including the CoordinatorLayout in an LinearLayout and making the second child(LinearLayout) become the first, by moving the Toolbar to the extrnal(root) level
Hierarchy before:
<CoordinatorLayout>
<AppBarLayout>
<ToolBar>
<LinerarLayout>
Hierarchy after:
<LinearLayout>
<ToolBar>
<CoordinatorLayout>
<AppBarLayout>
<LinearLayout>
An exmaple:
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout
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">
<androidx.appcompat.widget.Toolbar
android:layout_width="match_parent"
android:layout_height="48dp" />
<androidx.coordinatorlayout.widget.CoordinatorLayout
android:layout_width="match_parent"
android:layout_height="match_parent">
<com.google.android.material.appbar.AppBarLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:elevation="16dp">
<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:background="#color/colorSecondaryLight"
android:orientation="vertical"
app:layout_scrollFlags="scroll"/>
</com.google.android.material.appbar.AppBarLayout>
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.
.
</androidx.coordinatorlayout.widget.CoordinatorLayout>
</LinearLayout>
Hope that helps!
I have this layout:
<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|snap"/>
</android.support.design.widget.AppBarLayout>
<android.support.v7.widget.RecyclerView
android:id="#+id/recyclerView"
android:layout_width="match_parent"
android:layout_height="match_parent"
app:layout_behavior="#string/appbar_scrolling_view_behavior">
</android.support.v7.widget.RecyclerView>
<android.support.design.widget.FloatingActionButton
android:id="#+id/fabButton"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="end|bottom"
android:src="#drawable/ic_favorite_outline_white_24dp"/>
</android.support.design.widget.CoordinatorLayout>
Setting #string/appbar_scrolling_view_behavior attribute shifts the RecyclerView by the height of the Toolbar.
But what if I need the first element of the RecyclerView to be aligned to the status bar.
I want the Toolbar to cover (be above) the first element.
In other words, I don't want any offset which #string/appbar_scrolling_view_behavior behaviour entails.
Could you please tell me how to do that?
I had the same problem and I just wrapped the AppbarLayout and the rest of my views (in your case the recyclerview) in a RelativeLayout and it works fine. I don't know if there are any downsides with that approach.
The offset is not by #string/appbar_scrolling_view_behavior behaviour it's due to AppBarLayout it pushes the content down.
I'm not sure if there is any other better solution. But I'd suggest to remove the AppBarLayout to have your content go under the Toolbar. Moreover you might be need the scrolling behaviour for that you can check the library below.
It's been used by lots of apps like Jair Music Player even WhatsApp too uses it.
Library:
Android Observable Scroll View
Have a look at the following layout. You will see, that the floating button is too far to the bottom. This is because the Toolbar and the Tabs are shown and the height of the ViewPager is wrong. So somehow I'm doing something wrong with the layout_height. But how can I fix that?
Remark: The ViewPager is the main content and it contains a fragment with a ListView and a Google Map V2 in the second tab.
That's the layout 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"
android:layout_width="match_parent"
android:layout_height="match_parent">
<android.support.design.widget.AppBarLayout
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:layout_scrollFlags="scroll|enterAlways" />
<android.support.design.widget.TabLayout
android:id="#+id/sliding_tabs"
android:layout_width="match_parent"
android:layout_height="wrap_content"/>
</android.support.design.widget.AppBarLayout>
<android.support.v4.view.ViewPager
android:id="#+id/pager_list_views"
app:layout_behavior="#string/appbar_scrolling_view_behavior"
android:layout_width="match_parent"
android:layout_height="fill_parent">
</android.support.v4.view.ViewPager>
</android.support.design.widget.CoordinatorLayout>
Here's the layout for the fragment in the first tab (the list):
<?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"
android:layout_width="match_parent"
android:layout_height="match_parent">
<ListView
android:id="#+id/preview_list"
app:layout_behavior="#string/appbar_scrolling_view_behavior"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:choiceMode="singleChoice"
android:orientation="vertical" />
<android.support.design.widget.FloatingActionButton
android:id="#+id/action_add"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="end|bottom"
android:layout_margin="16dp"
android:src="#mipmap/ic_add_white_48dp" />
</android.support.design.widget.CoordinatorLayout>
Just to make sure; it's not a problem with the FAB. See this picture. It's a similar layout. A CoordinatorLayout with a ToolBar and a ViewPager which swipes through all detail-entries (therefore no tabs are needed). And again, the inner view seems to be too long (the same height as the ToolBar).
You should use android.support.v7.widget.RecyclerView and not ListView
Although you are already using android.support.v7.widget.RecyclerView be 100% sure that you have declard compile 'com.android.support:recyclerview-v7:23.0.0' in your build.gradle dependencies. I encountered the same issue where the viewpager overlaps the system buttons. I fixed it by simply adding this dependency.
Anything you what to be "coordinate" need to be direct child of CoordinatorLayout, Including the AppBar, RecyclerView (ListView in API21+ or other view support nested scroll is OK), or FAB, etc.
The reason why your FAB is offset out of screen, is that:
ViewPager has a #string/appbar_scrolling_view_behavior, the implement of this behavior will offset view when you scroll.
you put FAB inside ViewPager.
So when the offset of ViewPager changed, anything inside ViewPager will offset together (extra CoordinatorLayout has no help to change offset).
To fix this, don't use CoordinatorLayout outside ViewPager.
Or:
Put your FAB out of ViewPager so it won't scroll with ViewPager.
If the FAB only work with some of your page, hide() it when need.
BTW, there is very good App, Cheesesquare Sample, to demo the design library.