-import android.support.annotation.NonNull;
-import android.support.design.widget.Snackbar;
-import android.support.v4.app.ActivityCompat;
-import android.support.v4.app.DialogFragment;
-import android.support.v4.content.ContextCompat;
-import android.support.v4.widget.SwipeRefreshLayout;
-import android.support.v7.app.ActionBar;
-import android.support.v7.app.AppCompatActivity;
-import android.support.v7.app.AppCompatDialogFragment;
-import android.support.v7.widget.Toolbar;