Labels:book | reckoner | sky OCR: Lesson 19 1-99 method determined dynamically at runtime, technique explained in Part II as late- -binding. After the value of the second scroll bar is decremented by put: MyCtl stores the value in the second scroll bar's ivar before sending the update message the window. The importance of this myCtl mechanism Is that is eliminates the need 10J us to define five action handlers 10J each scrol! bar or concocting some algorithm to keep all that code to a minimum MyCtl allows us full control flexibility with a minimum ot code The doThumb definition special one that automatically calculates value based on the rela tive position of the thumb along the range of the scroll bar. The "doPgUp and doPgDn increment and decrement (respectively) the value of the scroll bar by 10 And the doLnUp and doLnDn ...
