Boa noite! Quando eu vou no Dependencies e coloco o cardview aparece o seguinte erro depois que o AndroidStudio processa o gradle. O cardview que aparece para eu colocar é o com.android.support:cardview-v7:26.0.0-alpha1.
Error:Execution failed for task ':app:processDebugManifest'.
Manifest merger failed : Attribute meta-data#android.support.VERSION@value value=(25.3.1) from [com.android.support:appcompat-v7:25.3.1] AndroidManifest.xml:27:9-31 is also present at [com.android.support:cardview-v7:26.0.0-alpha1] AndroidManifest.xml:24:9-38 value=(26.0.0-alpha1). Suggestion: add 'tools:replace="android:value"' to element at AndroidManifest.xml:25:5-27:34 to override.