android – CardView does not take up the full width of the screen even though it has the property of matching the parent

This time, I'm trying to make sure that a CardView can occupy the full width of the screen thanks to its layout_width = "match_parent" property, but when running from the </ p> As an application, these CardViews are displayed as if they were configured as "wrap_content".

The XML resource DEL LAOUT




    

        

            

            

                

                

                    

                    
                

                

                    

                    
                

            

        

    

IN THE APP (Gradle)

dependencies {
fileTree implementation (dir: 'libs', include: ['*.jar'])
implementation com.android.support: appcompat-v7: 28.0.0 & # 39;
implementation com.android.support.constraint: constraint-layout: 1.1.3 & # 39;
implementation com.android.support: design: 28.0.0 & # 39;
implementation: com.android.support: support-v4: 28.0.0 & # 39;
testImplementation & # 39; junit: junit: 4.12 & # 39;
androidTestImplementation com.android.support.test: runner: 1.0.2 & # 39;
androidTestImplementation & # 39; com.android.support.test.espresso: espresso-core: 3.0.2 & # 39;
implementation com.android.support: recyclerview-v7: 28.0.0 & # 39;
implementation com.android.support: cardview-v7: 28.0.0 & # 39;
implementation: com.android.support: percent: 28.0.0 & # 39 ;;
implementation: com.google.firebase: firebase-core: 16.0.5 & # 39;
implementation: com.google.firebase: firebase-auth: 16.0.5 & # 39;
implementation: com.google.firebase: firebase-database: 16.0.5 & # 39;
implementation: com.google.firebase: firebase-storage: 16.0.5 & # 39;
com.firebaseui implementation: firebase-ui-storage: 4.1.0 & # 39;

implementation com.github.bumptech.glide: glide: 4.8.0 & # 39;
annotationProcessor com.github.bumptech.glide: compiler: 4.8.0 & # 39;

}