nl_tokens: On Node enter see if it is valid for us to drop the field on that type of column .
pl_tokens: function ( target , dd , e , dragData ) { delete this . dropOK ; if ( ! <mask> ) { return ; } //      Check that a field is being dragged. var f = dragData . field ; if ( ! f ) { return ; } //      Check whether the data type of the column being dropped on accepts the //      dragged field type. If so, set dropOK flag, and highlight the target node. var type = target . record . fields . get ( target . fieldName ) . type , types = Ext . data . Types ; switch ( type ) { case types . FLOAT : case types . INT : if ( ! f . isXType ( 'numberfield' ) ) { return ; } break ; case types . DATE : if ( ! f . isXType ( 'datefield' ) ) { return ; } break ; case types . BOOL : if ( ! f . isXType ( 'checkbox' ) ) { return ; } } this . dropOK = true ; Ext . fly ( target . node ) . addCls ( 'x-drop-target-active' ) ; }