I had the same error when creating custom view with only one constructor, try to define all constructor for your custom views.
public CustomWebView(Context context) {
super(context);
init();
}
public CustomWebView(Context context, AttributeSet attrs) {
super(context, attrs);
init();
}
public CustomWebView(Context context, AttributeSet attrs, int defStyle) {
super(context, attrs, defStyle);
init();
}