Android Studio 2.2 Constraint Layout Buttons not visible

Question

Recently I was going through the tutorials of constraint layout (new in Android Studio 2.2). In the tutorials they had buttons used for constraints layout on the bar but there are no buttons in my Android Studio. See image below:

Solution

Add below-given dependencies in build.gradle(app)

dependencies {
    compile fileTree(include: ['*.jar'], dir: 'libs')

    compile 'com.android.support.constraint:constraint-layout:1.0.0-beta5'

}

Please do as shown below in your layout

Then after refreshing the project, click on the layout and all buttons will remain visible for yourself to work upon constraints.