CardView 上的透明背景 - Android

Question

I want to do transparent background on CardView. I know backgroundColor but i have image on my Layout.

Do you know how do it? Or something which work as cardview but i will set a transparent background?

Regards

Answer 1

Setup your CardView to use the cardBackgroundColor attribute to remove color and cardElevation attribute to remove the drop shadow. For example:

<android.support.v7.widget.CardView
    xmlns:card_view="http://schemas.android.com/apk/res-auto"
    xmlns:android="http://schemas.android.com/apk/res/android"
    android:id="@+id/myCardView"
    android:layout_width="match_parent"
    android:layout_height="match_parent" 
    card_view:cardBackgroundColor="@android:color/transparent"
    card_view:cardElevation="0dp"> 

For a full list of supported attributes see here: https://developer.android.com/reference/android/support/v7/widget/CardView.html

If you are using an older API, you will need to call these two functions on your CardView instead:

myCardView.setCardBackgroundColor(Color.TRANSPARENT);
myCardView.setCardElevation(0);

Answer 2

in SDK version 21 or higher steps to make Android CardView transparent.

1. Set android:backgroundTint="@android:color/transparent" . This is CardView attribute to set background.

2. Set android:cardElevation="0dp" to remove the shadow.

For example, here is small xml code to create transparent CardView

<androidx.cardview.widget.CardView
        xmlns:android="http://schemas.android.com/apk/res/android"
        xmlns:app="http://schemas.android.com/apk/res-auto"
        android:id="@+id/card_view"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        app:cardBackgroundColor="@android:color/transparent"
        app:cardElevation="0dp" />

Answer 3

In my case, I used the attribute android:backgroundTint="@color/some_color" ,it is only used en API level 21 and higher . And color #50000000 for example.

<android.support.v7.widget.CardView
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        card_view:cardCornerRadius="3dp"
        app:cardElevation="0dp"
        android:backgroundTint="@color/negro_label"
        >

Answer 4

use app:cardBackgroundColor="@android:color/transparent"

<android.support.v7.widget.CardView
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:layout_marginBottom="20dp"
    android:layout_marginLeft="20dp"
    android:layout_marginRight="20dp"
    android:layout_marginTop="10dp"
    app:cardCornerRadius="16dp"
    app:cardElevation="16dp"
    app:cardBackgroundColor="@android:color/transparent" >

<--inside cardlayout-->

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

Answer 5

这应该适用于API 17

cardView.setBackgroundColor(ContextCompat.getColor(getContext(), android.R.color.transparent));

Answer 6

Just add background color app:cardBackgroundColor="#0000"

<androidx.cardview.widget.CardView
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    app:cardBackgroundColor="#0000"> 

Answer 7

You must have cardView to make image circle shape

       <androidx.cardview.widget.CardView
            android:layout_width="50dp"
            android:layout_height="50dp"
            app:cardCornerRadius="25dp"
            android:layout_centerHorizontal="true"
            android:layout_centerVertical="true"
            android:elevation="0dp"
            app:cardBackgroundColor="#00424242"
            >

            <ImageView
                android:layout_width="match_parent"
                android:layout_height="match_parent"
                android:scaleType="centerCrop"
                android:src="@drawable/play_icon"
                android:padding="5dp"
                android:background="#19000000"
                android:contentDescription="TODO" />

        </androidx.cardview.widget.CardView>