Develop Reference

android - how to put shadow on just the top edge of rounded cardview?

[![my image][1]][1]
As. you can see from the image i have a rounded corner shape ..but i want to have a shadow just on the top (there is no where else for it anyway since its covered on the other ends). How can i place a shadow just at the top of this cardView ? here is what i have so far and i've tried using two framelayouts earlier.
<?xml version="1.0" encoding="utf-8"?>
<androidx.constraintlayout.widget.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:id="#+id/viewRoot"
android:layout_width="match_parent"
android:layout_height="wrap_content">
<com.google.android.material.card.MaterialCardView
android:theme="#style/Theme.MaterialComponents.Light"
android:id="#+id/greenCardView"
android:layout_width="match_parent"
android:layout_height="100dp"
app:layout_constraintTop_toTopOf="parent"
app:layout_constraintLeft_toLeftOf="parent"
app:layout_constraintRight_toRightOf="parent"
app:cardCornerRadius="16dp"
app:cardElevation="0dp"
android:clipToOutline="true"
android:clipToPadding="true"
android:clipChildren="true"
app:cardPreventCornerOverlap="true"
app:cardBackgroundColor="#color/green">
<androidx.constraintlayout.widget.ConstraintLayout
android:id="#+id/contentContainer"
android:layout_width="match_parent"
android:background="#color/transparent"
android:layout_height="54dp"/>
</androidx.constraintlayout.widget.ConstraintLayout>
i also need the shadow to have no background under it ..so it should not be on a white background, i just want the shadow on top alone on a transparent background.
update: after i udated to 70dp elevation the shadow is only appearing on the bottom :
[![enter image description here][2]][2]
notice the shadow is only appearing at the bottom . how can i make shadow just at the top
[1]: https://i.stack.imgur.com/8XC6l.png
[2]: https://i.stack.imgur.com/egRoB.png

Increse the value of
app:cardElevation="0dp"

it was how i was attaching the scrollview to the cardview ..i used a space view to attach it a bit lower and it works great now (since i dont have access to negative margins) ..thanks
what i learned is that when you have a scrollview attached to a cardview then you should attach the scrollview a few pixels away from the top so that it does not look cut off when it scrolls.

Cardview - rounded corners with transparent background

I am trying something that I didnt think would take hours.
I want a cardview with a transparent background and slightly rounded corners.
In the end it should look like this (the pink item at the top is some other view):
This is how far I have got:
Actually I thought I am done, and I just need to round the corners, and remove the stroke from the cardview. Well, it seems like these 2 things are not possible. When I set app:cardCornerRadius="8dp" this is the output I get:
Removing the stroke didn' work at all. In the end I created a rectangle shape inside drawable (where I set the stroke to 0dp), assigned it to the cardview and the stroke was gone, but I got a white background behind the rounded corners and I wasnt able to remove it.
This is my CardView Layout:
<androidx.cardview.widget.CardView
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_margin="15dp"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:foreground="?android:attr/selectableItemBackground"
android:clickable="true"
android:elevation="0dp"
app:cardCornerRadius="8dp"
app:cardPreventCornerOverlap="true"
app:cardBackgroundColor="#00123456"
> </CardView>
Is there a possibility to achive what I want (first pic)? Or should I let go of RecyclerView switch to ListView?

Removing the CardView as the parent and putting a Constraintlayout, solved the problem.
<androidx.constraintlayout.widget.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="wrap_content"
android:layout_marginLeft="8dp"
android:layout_marginRight="8dp"
android:background="#drawable/rounded_background"
android:clickable="true"
android:foreground="?android:attr/selectableItemBackground"
android:paddingTop="4dp"></ConstraintLayout>

Shadow on CardView within ConstraintLayout not showing

I have a CardView within a ConstraintLayout.
This view is then inflated and added to a LinearLayout.
I would like the CardView to cast a shadow on the next CardView, but it seems to be clipped by the ConstraintLayout. How can I get the elevation shadow to show on the CardView without providing more padding or margins for it?
i.e. How can I cast the shadow on an adjacent item?
<LinearLayout>
<ConstraintLayout>
<CardView> <-- This view's shadow is cut
...
</CardView>
</ConstraintLayout>
<ConstraintLayout>
<CardView>
...
</CardView>
</ConstraintLayout>
<LinearLayout>

Try adding this comment inside your card view that's enough
card_view:cardUseCompatPadding="true"

How can I get the elevation shadow to show on the CardView without providing more padding or margins for it?
i.e. How can I cast the shadow on an adjacent item?
You can't, for both a practical reason and a conceptual one.
The practical reason comes down to how the Android framework draws CardView shadows. On older API levels, the card is inset within its own bounds and that extra space is used to draw the shadow. So even if you had two cards immediately next to each other, they'd still have "space" between them due to these insets. From the documentation:
Before Lollipop, CardView adds padding to its content and draws shadows to that area.
On Lollipop and higher, shadows are drawn within the parent's bounds, not within the CardView's bounds. Still, the parent will clip the shadow if there isn't enough space between the card's edges and the parent's edges to draw the whole shadow. In your example, each CardView is in a separate parent, so even if you put those parents immediately next to each other, each parent would still clip its card's shadow.
As for the conceptual reason, that's just not how shadows work (in nature). If you have two cards at the same elevation, even if they're right next to each other, the top card wouldn't cast a shadow on the bottom card.

Try to add
app:cardElevation="10dp"
In order to use app:cardElevation you have to add to your LinearLayout:
xmlns:app="http://schemas.android.com/apk/res-auto"
I tried this in a test project and the elevation should work this way. Below is my code:
<?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"
tools:context="ro.helpproject.funcode.help.MainActivity">
<android.support.constraint.ConstraintLayout
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="center">
<android.support.v7.widget.CardView
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_margin="50dp"
app:cardElevation="10dp">
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="TEST TEST" />
</android.support.v7.widget.CardView>
</android.support.constraint.ConstraintLayout>
<android.support.constraint.ConstraintLayout
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="center">
<android.support.v7.widget.CardView
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_margin="50dp"
app:cardElevation="10dp">
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="TEST TEST" />
</android.support.v7.widget.CardView>
</android.support.constraint.ConstraintLayout>
</LinearLayout>

CardView needs padding around it for shadow to appear.
If app:cardUseCompatPadding="true" adds the shadow for you but you don't want the extra padding from 4 directions (LRTB), you need to add margin to the CardView yourself.
Enable Developer options -> Show layout boundaries and if you see that there is no empty space around your CardView. Then that's probably the reason shadow not appearing.

Make over scroll glow be outside the padding

I have the following:
<android.support.v7.widget.RecyclerView
android:id="#+id/list"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:scrollbars="vertical" />
I add this for a cleaner UI:
android:paddingEnd="16dp"
android:paddingStart="16dp"
However, now the scroll bar is inside the padding and looks funky. So I add:
android:scrollbarStyle="outsideInset"
The scroll bar is now outside the padding, however, the over scroll glow is still inside the padding.
How do I get the over scroll glow to stretch across the padding?
EDIT:
Here's the full layout code that encounters the same issue as above.
<?xml version="1.0" encoding="utf-8"?>
<android.support.v7.widget.RecyclerView 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/recycler_view"
android:layout_width="match_parent"
android:layout_height="match_parent">
</android.support.v7.widget.RecyclerView>

What you need to do is to apply android:clipToPadding="false" to RecyclerView. Consider this xml:
<android.support.v7.widget.RecyclerView
android:layout_width="match_parent"
android:layout_height="match_parent"
android:paddingTop="40dp"
android:paddingBottom="40dp"
android:clipToPadding="false"/>
Here's the result:

Your best bet would be to put padding inside RecyclerView's item layout and not on RecyclerView itself.
However, you could just use margins and the glow should stay inside the RecyclerView.

While the answer given by #azizbekian works, it's also possible to set clipToPadding programmatically.
In Kotlin: recyclerView.clipToPadding = false
In java: recyclerView.setClipToPadding(false)
My personal favorit is to extend RecyclerView and set a LayoutManager, clipToPadding and such in the init function (constructor).

Android ScrollView clipping child elevation shadow [duplicate]

This question already has answers here:
Android "elevation" not showing a shadow
(23 answers)
Closed 5 years ago.
As the title states, I'm trying to put a CardView inside a ScrollView, but the CardView elevation shadow is being but off by it's parent...
This is the Layout XML:
<FrameLayout
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=".TestScrollViewActivity">
<android.support.v7.widget.Toolbar
android:id="#+id/toolbar"
android:layout_width="match_parent"
android:layout_height="128dp"
android:background="?colorPrimary"
android:gravity="bottom"
android:minHeight="?actionBarSize"/>
<ScrollView
android:layout_width="wrap_content"
android:layout_height="match_parent"
android:layout_gravity="center_horizontal"
android:clipToPadding="false"
android:paddingBottom="40dp"
android:paddingTop="60dp">
<android.support.v7.widget.CardView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:elevation="4dp"
app:cardBackgroundColor="#android:color/white"
app:cardCornerRadius="0dp">
<LinearLayout
android:layout_width="400dp"
android:layout_height="600dp"
android:orientation="vertical">
</LinearLayout>
</android.support.v7.widget.CardView>
</ScrollView>
</FrameLayout>
The only workaround that I found is to add a padding to the parent ScrollView or add a margin to the child CardView...
Is there any option to prevent this from happening without using a padding/margin?
Thanks.
Edit:
This is how the layout looks like without setting a padding on the parent scroll view, as it can be seen, the left and right shadows are being cut off:
Now, if a padding is added to the parent scrollview sides, the shadows are being drawn correctly as it can be seen here:
So, my main question here is this the only way to achieve that?, or there is a tag or a configuration on the parent view that allow to correctly draw it's children views?

this just worked for me in a similar problem:
the right way to get a child view to show shadow is to set padding on the parent and set android:clipToPadding="false" on that parent.
as found here: Android "elevation" not showing a shadow

I was facing the same problem, I solved it by adding cardUseCompatPadding attribute to the card view:
app:cardUseCompatPadding="true"
The shadow will not be cut out or cropped after using this solution.

This work for me adding cardUseCompatPadding attribute to the card view:
set android:clipToPadding="false" on that parent.