android - How to set CardView corner radius

activity_main.xml

 <?xml version="1.0" encoding="utf-8"?> <RelativeLayout     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"     android:padding="16dp"     tools:context=".MainActivity"     android:background="#ffffff"     >     <!--         CardView             A FrameLayout with a rounded corner background and shadow.             CardView uses elevation property on L for shadows and falls back to a custom shadow             implementation on older platforms.     -->     <!--         android.support.v7.cardview:cardCornerRadius             Corner radius for CardView.             Must be a dimension value, which is a floating point number appended with a unit such             as "14.5sp". Available units are: px (pixels), dp (density-independent pixels), sp             (scaled pixels based on preferred font size), in (inches), mm (millimeters).              This may also be a reference to a resource (in the form "@[package:]type:name") or             theme attribute (in the form "?[package:][type:]name") containing a value of this type.              This is a private symbol.          Related Methods             setRadius(float)     -->     <android.support.v7.widget.CardView         xmlns:card_view="http://schemas.android.com/apk/res-auto"         android:id="@+id/card_view_top"         android:layout_width="wrap_content"         android:layout_height="wrap_content"         card_view:cardCornerRadius="6dp"         card_view:contentPadding="25dp"         card_view:cardElevation="4dp"         card_view:cardMaxElevation="6dp"         card_view:cardBackgroundColor="#0077ff"         >         <TextView             android:layout_width="wrap_content"             android:layout_height="wrap_content"             android:text="CardView Corner Radius In XML File"             android:textSize="20sp"             android:textStyle="bold"             android:layout_gravity="center"             android:gravity="center"             />     </android.support.v7.widget.CardView>     <android.support.v7.widget.CardView         xmlns:card_view="http://schemas.android.com/apk/res-auto"         android:id="@+id/card_view_bottom"         android:layout_width="wrap_content"         android:layout_height="wrap_content"         card_view:contentPadding="25dp"         android:layout_below="@id/card_view_top"         card_view:cardElevation="4dp"         card_view:cardMaxElevation="6dp"         card_view:cardBackgroundColor="#0077ff"         >         <TextView             android:layout_width="wrap_content"             android:layout_height="wrap_content"             android:text="CardView Corner Radius In Java File"             android:textSize="20sp"             android:textStyle="bold"             android:layout_gravity="center"             android:gravity="center"             />     </android.support.v7.widget.CardView> </RelativeLayout> 

MainActivity.java

 package com.cfsuman.me.androidcode;  import android.content.Context; import android.graphics.Color; import android.graphics.drawable.ColorDrawable; import android.support.v7.app.AppCompatActivity; import android.os.Bundle; import android.support.v7.widget.CardView; import android.view.Window;   public class MainActivity extends AppCompatActivity {     private Context mContext;      private CardView mCardViewTop;     private CardView mCardViewBottom;       @Override     protected void onCreate(Bundle savedInstanceState) {         // Request window feature action kafetaria         requestWindowFeature(Window.FEATURE_ACTION_BAR);         super.onCreate(savedInstanceState);         setContentView(R.layout.activity_main);          // Get the application context         mContext = getApplicationContext();          // Change the action kafetaria color         getSupportActionBar().setBackgroundDrawable(new ColorDrawable(Color.parseColor("#FFFF0004")));          // Get the widgets reference from XML layout         mCardViewTop = (CardView) findViewById(R.id.card_view_top);         mCardViewBottom = (CardView) findViewById(R.id.card_view_bottom);          /*             public void setRadius (float radius)                 Updates the corner radius of the CardView.              Related XML Attributes                 android.support.v7.cardview:cardCornerRadius              Parameters                 radius : The radius in pixels of the corners of the rectangle shape         */          // Set the CardView corner radius programmatically         mCardViewBottom.setRadius(9);     } } 

build.gradle [dependencies]

 compile 'com.android.support:cardview-v7:23.0.1'