` Using filtered locators (Dennis E. Evans) - Icetips Article
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ABC: Using filtered locators
1998-12-31 -- Dennis E. Evans
 
Newsgroups: topspeed.products.c5pe >All the replys where helpfull but not what I was looking for. What I would >like to do is take a value entered by the user and scroll to the next record >that contains the texted. Clarion has some pretty nice query fuctions and >even the incremental search is nice but sometimes you don't know the exact >spelling and doing a query on a large file takes forever. Access has this >feature built-in and I would think Clarion(Topspeed) could do the same. I had a similar request in an application a while back, the user even mentioned Access. I really did not want to try and explain the different ways a page loaded browse worked and how Access works. Not sure this is what you are looking for, I debated about posting but it may give you a couple of ideas. As with all problems in this business there is probably a half a dozen other ways to solve it, but this one does work and is fairly simple. I did this originally in CW4b and all seems to be well since I upgraded. Performance is not what you would call blinding fast but is acceptable, it has to be as fast as a sequential search. This has been used on a file with just over 30,000 records not huge but fair sized. And finally the solution : Open the embed editor and add local variable to be used for the user input and a class instance of the FilterLocatorClass to be used to set the filter stuff. WorkStr string(20) ! or whatever you need FindItLocator FilterLocatorClass in the Window.Init method, after the browse is initialized, initialize the locator: FindItLocator.Init(,Fil:KeyFielName,1,BRWx) FindItLocator.FloatRight = true Note there is no control passed in the init method call. The browse does not know about the locator but the locator knows about the browse. The Float right property is what allows the filter expression to use the instring condition. In the Window.Kill method add this FindItLocator.Destruct() ! nulls the FreeElement field, which is an ANY type. Add an entry control to the tab needed In the control event handling 'Accepted' add this : if WorkStr = '' FindItLocator.Set() ! clear the locator FindItLocator.UpdateWindow() ! clear the filter condition Brwx.UpdateBuffer() ! make sure the buffer is loaded Brwx.ResetFromBuffer() ! reset from the buffer else FindItLocator.Shadow = clip(WorkStr) ! set the shadow FindItLocator.UpdateWindow() ! add to filter Brwx.ResetQueue(Reset:Queue) ! redisplay the browse end ! if Now what happens is when the user enters something like 'on' and presses the tab key. All fields with 'on' will be displayed. Jones, Johnson, On Sale, etc... They can then add to the condition or work with what they have. When they are done all the user needs to do is blank the workstr variable and the browse is redisplayed and the current record will be highlighted. Again not sure this is what you are looking for but may get you started. Hope it helps. Dennis


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