Q:

The IDE can't open library dependency dialog (Maven dependency)

After upgrade Android Studio to 1.2.1.1 Or later , The IDE can't open library dependency dialog (Maven dependency)
it gives this error :
Could not initialize class com.android.tools.idea.structure.gradle.MavenDependencyLookupDialog

is it a bug ,, or some thing Wrong ??

A:

I Found it Finally , in new versions of android studio 
you should activate the Maven box from :
new SDK Manager >> Plugins >> Maven Integration >> check this box

A:

I used @Maher Answer and tried to show graphically
Step 1: In android studio Open Tools > Android > Sdk Manager

Step 2: Now click or Plugin > Maven Integration and mark checked

