CardView not showing shadow elevation

问题

I am working with cardviews but the problem is my CardView is not showing any elevation or shadow. I have already tried some of the methods suggested in stackoverflow answers like I have tried using elevation and shadow property. I have also tried using card_view:cardUseCompatPadding="true", but without any success. This is my xml file

<?xml version="1.0" encoding="utf-8"?>
<android.support.v7.widget.CardView
    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="wrap_content"
    xmlns:card_view="http://schemas.android.com/tools"
    android:layout_marginLeft="12dp"
    android:layout_marginRight="12dp"
    android:layout_marginTop="6dp"
    android:layout_marginBottom="6dp"
    app:cardBackgroundColor="#FAFBFD"
    app:cardElevation="5dp">

    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:orientation="vertical">

        <RelativeLayout
            android:layout_width="match_parent"
            android:layout_height="wrap_content">

            <de.hdodenhof.circleimageview.CircleImageView
                android:id="@+id/post_profile_image"
                android:layout_width="50dp"
                android:layout_height="50dp"
                android:src="@mipmap/ic_launcher"
                android:layout_marginLeft="12dp"
                android:layout_marginTop="12dp"/>

            <LinearLayout
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:layout_toRightOf="@id/post_profile_image"
                android:layout_marginLeft="12dp"
                android:orientation="vertical"
                android:layout_marginTop="16dp">

                <TextView
                    android:id="@+id/post_username"
                    android:layout_width="wrap_content"
                    android:layout_height="wrap_content"
                    android:text="Name"
                    android:textAppearance="?android:attr/textAppearanceMedium"
                    android:textColor="#000000"/>

                <TextView
                    android:id="@+id/post_time"
                    android:layout_width="wrap_content"
                    android:layout_height="wrap_content"
                    android:layout_marginTop="2dp"
                    android:text="Time"
                    android:textAppearance="?android:attr/textAppearanceSmall"
                    android:textColor="@color/grayColor"/>
            </LinearLayout>

            <LinearLayout
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:layout_alignParentRight="true">

                <ImageButton
                    android:layout_width="wrap_content"
                    android:layout_height="wrap_content"
                    android:background="@android:drawable/ic_delete"
                    android:id="@+id/post_delete_btn"
                    android:visibility="invisible"/>

            </LinearLayout>

        </RelativeLayout>

        <ImageView
            android:id="@+id/post_image"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:layout_centerHorizontal="true"
            android:layout_marginTop="12dp"
            android:adjustViewBounds="true"
            android:background="#00ffffff"
            android:src="@drawable/add_btn"
            android:visibility="gone"/>

        <TextView
            android:id="@+id/post_text"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_marginTop="12dp"
            android:layout_marginLeft="12dp"
            android:text="Text about Posting...."
            android:textAppearance="?android:attr/textAppearanceMedium"/>

        <LinearLayout
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:layout_marginTop="12dp"
            android:layout_marginBottom="8dp">

            <ImageButton
                android:id="@+id/like_btn"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:layout_marginLeft="12dp"
                android:background="#00ffffff"
                android:src="@drawable/grey_like_bt"/>

            <TextView
                android:id="@+id/post_like_count"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:layout_marginLeft="4dp"
                android:layout_marginTop="8dp"
                android:text="0 Likes"
                android:textColor="#2196F3"/>

            <ImageButton
                android:id="@+id/comment_btn"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:layout_marginLeft="32dp"
                android:background="#00ffffff"
                android:src="@drawable/comment_btn_gray"/>

            <TextView
                android:id="@+id/post_comment_count"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:layout_marginLeft="4dp"
                android:layout_marginTop="8dp"
                android:text="0 Comments"
                android:textColor="#2196F3"/>

            <RelativeLayout
                android:layout_width="wrap_content"
                android:layout_height="wrap_content">

                <ImageButton
                    android:layout_width="wrap_content"
                    android:layout_height="wrap_content"
                    android:background="@android:drawable/ic_menu_edit"
                    android:visibility="invisible"
                    android:id="@+id/post_edit_btn"
                    android:layout_alignParentRight="true"/>

            </RelativeLayout>

        </LinearLayout>

    </LinearLayout>

</android.support.v7.widget.CardView>

Dont know why it is not showing any elevation and shadow

回答1:

Do not forget that to draw shadow you must use hardwareAccelerated drawing

<application android:hardwareAccelerated="true" ...>

see for details https://developer.android.com/guide/topics/graphics/hardware-accel.html?hl=ru

回答2:

<android.support.v7.widget.CardView android:id="@+id/item_card"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    app:cardCornerRadius="2dp"
    app:cardUseCompatPadding="true"
    app:cardElevation="2dp"
    app:cardBackgroundColor="@color/md_white_1000"
    android:foreground="?android:attr/selectableItemBackground"
    android:clickable="true">

</android.support.v7.widget.CardView>

app:cardUseCompatPadding="true" is the main catch here

回答3:

If your manifest file has a android:hardwareAccelerated="false" line, delete it.

回答4:

There are two things you have missing.

First of all, Check your project's AndroidManifest.xml file in the Application tag you have to write

<application android:hardwareAccelerated="true" ...>

instead of

<application android:hardwareAccelerated="false" ...>

the second one is, check the parent tag of your layout file is there written like below line.
if you wanna use app: xmlns. then write : xmlns:app="http://schemas.android.com/apk/res-auto"
if you wanna use card_view: xmlns. then write : xmlns:card_view="http://schemas.android.com/apk/res-auto"

NOTE: you don't need to write both simultaneous. Because it gives you duplicate attribute error.

for more understanding see: https://stackoverflow.com/a/56206240/7832102

The above line is most important when you use the attributes of res-auto.

<?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="wrap_content"
    android:orientation="vertical">

    <android.support.v7.widget.CardView
        android:id="@+id/card_view"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        app:cardBackgroundColor="@android:color/white"
        app:cardCornerRadius="4dp"
        app:cardElevation="4dp" />

</RelativeLayout>

回答5:

The answer is a combination of margin and padding of cardView and its parent.

Try like this:

    <android.support.v7.widget.CardView
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:layout_marginBottom="@dimen/minimum_dimem"
            android:layout_marginLeft="@dimen/default_margin"
            android:layout_marginRight="@dimen/default_margin"
            android:layout_marginTop="@dimen/minimum_dimem"
            app:cardBackgroundColor="@color/white"
            app:cardCornerRadius="@dimen/cardview_radius"
            app:cardElevation="@dimen/cardview_default_elevation">

            <RelativeLayout
                android:layout_width="match_parent"
                android:layout_height="wrap_content"
                android:orientation="vertical"
                android:padding="@dimen/ten_dimem">

                ...

           </RelativeLayout>
</android.support.v7.widget.CardView>

And the result:

回答6:

You should have to try this:

<android.support.v7.widget.CardView
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_margin="5dp"
        app:cardElevation="3dp">

        <LinearLayout
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:orientation="vertical">
        </LinearLayout>

        <!--Put your other fields between this-->
</android.support.v7.widget.CardView>

回答7:

Try this

    <android.support.v7.widget.CardView
            android:id="@+id/driverCurrentJobsCardView"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:layout_margin="@dimen/dim_8"
            android:background="#ffffff"
            app:cardCornerRadius="4dp"
            card_view:cardElevation="4dp"/>

And make sure that you are using this dependency in gradle

compile 'com.android.support:cardview-v7:23.2.1'

回答8:

use this inside cardView to show shadow:

app:cardElevation="4dp"
app:cardMaxElevation="4dp"

回答9:

<android.support.design.card.MaterialCardView
    xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:card_view="http://schemas.android.com/tools"
    app:cardCornerRadius="@dimen/_5sdp"
    card_view:cardCornerRadius="3dp"
    android:layout_margin="@dimen/_3sdp"
    card_view:cardElevation="10dp"
    card_view:cardUseCompatPadding="true">
</android.support.design.card.MaterialCardView>

Use above code and don't forget to use android:hardwareAccelerated="true". It will work definitely.

回答10:

Try putting this in your rootview:

xmlns:card_view="http://schemas.android.com/apk/res-auto"

and use this code for elevation:

card_view:cardElevation="10dp"

回答11:

Add this line in CardView widget

app:cardElevation="5dp"

hope this will help!

回答12:

     <android.support.v7.widget.CardView
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    app:cardElevation="10dp"
    app:cardCornerRadius="4dp"
    app:cardBackgroundColor="#ffff8800">
     ......
     </android.support.v7.widget.CardView>

Remove the background color first, add the elevation and later add the background again. Worked for me, though I had added the background through the layout designer.

回答13:

remove below line from AndroidManifest.xml

android:hardwareAccelerated="false"

回答14:

Try adding android:outlineProvider="bounds" to the CardView layout.

回答15:

<android.support.v7.widget.CardView
    xmlns:card_view="http://schemas.android.com/apk/res-auto"
    android:id="@+id/card_view"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    app:cardBackgroundColor="@android:color/white"
    android:foreground="?android:attr/selectableItemBackground"
    android:layout_marginLeft="@dimen/activity_horizontal_margin"
    android:layout_marginRight="@dimen/activity_horizontal_margin"
    android:layout_marginTop="@dimen/padding_small"
    android:layout_marginBottom="@dimen/padding_small"
    app:cardCornerRadius="4dp"
    app:cardElevation="4dp" >

</android.support.v7.widget.CardView>

来源：https://stackoverflow.com/questions/43406938/cardview-not-showing-shadow-elevation

标签

android

xml

android-cardview