Omitting "@aar" in gradle cause app to crash

[orbegoso]

compile 'com.cocosw:undobar:1.+'
Causes the app to crash at the line
UndoBarController.show(mActivity, "Item removed", ItemSwipeListener.this, bundle);
With the error

'void android.widget.TextView.setOnClickListener(android.view.View$OnClickListener)' on a null object reference
However, using'com.cocosw:undobar:1.+@aar' to compile works fine. Also using this way asks me to implement "onClear", but it doesn't when the @aar isn't there.

[soarcn]

I've changed readme and added "@aar" back, thanks for this.