Develop Reference

Gray horizontal line pre lollipop cardview on bottom

I am trying to get rid of this gray line on my cardview
I am using a color with a bit of transparency - #40B6F2FC
here is my code
<android.support.v7.widget.CardView
android:id="#+id/cardView"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:dividerHeight="0px"
android:divider="#null"
app:cardPreventCornerOverlap="false"
app:cardBackgroundColor="#color/sky_colorBlue_20_percent"
app:cardCornerRadius="2dp"
app:cardElevation="2dp"
app:cardMaxElevation="2dp"
app:cardUseCompatPadding="true">
Followed the answer of this question https://stackoverflow.com/a/18734605/1599611 but still didnt work.
Is there a way to get rid of this grayline without setting the elevation to zero and using a color with transparency added?

Base from this tracker
https://issuetracker.google.com/issues/37008169
Status: Won't Fix (Intended Behavior) CardView does not support
transparency for its background. This is due to limitations of drawing
shadows using canvas api.

Android UI component

Hello can you tell me how can I add the rectangular box in the android layout which adds up like a 3d effect as in the below screenshot. Thanks.

You can add this effect to almost every view or widget, using android:elevation attribute, or programmatically using setElevation(x) method. X is number of Dp.
Note: This only works on api level 21 or newer.

you are referring to material design you can add this effect using card view

Add elevation to your view
read this documentation for assigning elevation to your view
https://developer.android.com/training/material/shadows-clipping.html

Add dependency compile 'com.android.support:cardview-v7:23.0.1'
<android.support.v7.widget.CardView
android:id="#+id/card_view"
xmlns:card_view="http://schemas.android.com/apk/res-auto"
android:layout_width="match_parent"
android:layout_height="wrap_content"
card_view:cardBackgroundColor="#color/grey_300"
card_view:cardCornerRadius="5dp"
card_view:cardElevation="5dp"
card_view:cardUseCompatPadding="true">

Shadow of CardView not visible on Android Lollipop

Following code works perfectly on Kitkat, but shadows are not visible in Lollipop.
Actually I can see shadow in Android Studio Preview, but not while running on a device/emulator. I'm using CardView for adapter of ViewPager (android.support.v4.view.ViewPager)
<android.support.v7.widget.CardView
xmlns:card_view="http://schemas.android.com/apk/res-auto"
android:layout_width="match_parent"
android:layout_height="match_parent"
card_view:cardUseCompatPadding="true"
card_view:cardCornerRadius="4dp"
card_view:cardElevation="6dp">

Actually it also shows shadow in L version, but it is based on elevation so you can't see the shadow if card height is match parent
try adding margin to card if you want to see shadow

Found the solution. I'm able to get the shadow effect using following code.
android:background="#android:drawable/dialog_holo_dark_frame"

Android CardView with a custom shadow color

Is it possible to change the color of the shadow around the CardView? Mainly used to mark selected the card as it were lighted on?
Should be valid on L and pre-L devices.

CardView shadow colors are defined in the resources of the CardView library. You can override them by redefining the resource value in your own project but you can not change them dynamically by code.
Edit: overriding the resource value only affects pre-Lollipop devices. On Lollipop and above, CardView always uses the native shadow implementation whose color cannot be changed.

Update: Check my modification.
Here's a workaround:
Copy the source code of CardView. Then create your own Android Library Module and use this module instead of support library. After these, comment or remove code in CardView like below:
static {
// if (Build.VERSION.SDK_INT >= 21) {
// IMPL = new CardViewApi21Impl();
// } else
if (Build.VERSION.SDK_INT >= 17) {
IMPL = new CardViewApi17Impl();
} else {
IMPL = new CardViewBaseImpl();
}
IMPL.initStatic();
}
That is, you will use compat-version CardViewApi17Impl even when api is 21 or higher. Then, you can define your own cardview_shadow_start_color and cardview_shadow_end_color to override those in class RoundRectDrawableWithShadow. Furthermore, you can make that more customizable.
Hope can help someone.

I've used a small trick. One CardView is put behind another one. Both are the same, difference is card_view:cardElevation="10dp" for background one, and card_view:cardElevation="2dp" for faced one. The subtraction of elevation provides how long is your shadow, and color of the second CardView gonna be color of the shadow for first one.
Example:
<android.support.v7.widget.CardView xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:card_view="http://schemas.android.com/apk/res-auto"
android:id="#+id/view_click_basement"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_marginBottom="2dp"
card_view:cardCornerRadius="5dp"
card_view:cardBackgroundColor="#color/colorNewGreen"
card_view:cardElevation="10dp"
card_view:cardUseCompatPadding="true">
<android.support.v7.widget.CardView
android:id="#+id/view_click"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_marginBottom="2dp"
card_view:cardCornerRadius="5dp"
card_view:cardElevation="2dp"
card_view:cardUseCompatPadding="true">

Try this :-
android:outlineSpotShadowColor="#color/"
android:outlineAmbientShadowColor="#color/"

Android 5.0 does not respect view's margins

I have an app that runs well in any version of android, but in Lollipop seems that all views don't respect any margin or padding.
Does anyone know why??
Thanks in advance.
I'm declaring the CardView like this:
<android.support.v7.widget.CardView xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:card_view="http://schemas.android.com/apk/res-auto"
android:id="#+id/card_view1"
android:background="#color/backgroundItem"
android:layout_width="match_parent"
android:layout_height="fill_parent"
android:layout_marginRight="2dp"
android:layout_marginLeft="2dp"
card_view:cardCornerRadius="0dp"
android:layout_weight="1">

Per the CardView documentation:
Note that, if you specify exact dimensions for the CardView, because of the shadows, its content area will be different between platforms before L and after L. By using api version specific resource values, you can avoid these changes. Alternatively, If you want CardView to add inner padding on platforms L and after as well, you can set setUseCompatPadding(boolean) to true.