Mailing List Archive: 49091 messages
  • Home
  • Script library
  • AltME Archive
  • Mailing list
  • Articles Index
  • Site search
 

How to count properly slider args solution ....

 [1/1] from: petr::krenzelok::trz::cz at: 30-Aug-2000 13:55


Hi, as I was receiving unexpected behavior of lists while trying to scroll it (when using 'supply for dynamic list creation), I played a little bit with what should be the right arg which should go into slider ... I surely don't know how /View scrolls internally, but imho following aproach used even by Carl's file-requestor is imho buggy and will not show all items. If I am wrong, I will be glad you will correct me please :-) Carl uses following technique: vv: slider 16x400 (to-integer vx/size/y / file-name/size/y) [print vv/data num: vv/data - 1 show vx] while num and count being initialised to zero So, current aproach gave me 58 items of my directory .... I took another aproach: 1 + (length? files) - (to-integer vx/size/y / file-name/size/y) Explanation: 1) "1" is the constant - it simply works ;-))) 2) Now we have to count, how many rows our visible list area can display .... (to-integer vx/size/y / file-name/size/y) 3) We have to substract value 2) from the length? of block we want list be filled with ... If I count items in display now, it give more proper result of 154 files ... Still one file missing though .... :-) Hmm, what about this one?: - there's some reminder as a result from 2) (to-integer vx/size/y / file-name/size/y). Let's say we can ignore those few pixels with small listings, but - going thru some 5 screens gives me: reminder vx/size/y file-name/size/y ..... 400 // 14 = 5 pixels ... 5 pixels * 5 screens = 25 displays ... hmm, it's one more item for the display ... So: length? read %. .... 155 files y-size-of-list / item-size .... 400 / 14 .... 28 items per screen .... reminder 8 pixels ... 155 files / 28 items .... 5 full screens to display .... 5 screens * 8 pixels .... 40 pixels ... 40 pixels / 14 pixels per item ..... 2 more items ... so, let's code it: items-per-screen: to-integer vx/size/y / file-name/size/y full-screens: to-integer (length? files) / items-per-screen remainder-per-screen: remainder vx/size/y file-name/size/y constant: to-integer full-screens * remainder-per-screen / file-name/size/y range: constant + (length? files) - items-per-screen resulting code in file-request.r: .... do [ items-per-screen: to-integer vx/size/y / file-name/size/y full-screens: to-integer (length? files) / items-per-screen remainder-per-screen: remainder vx/size/y file-name/size/y constant: to-integer full-screens * remainder-per-screen / file-name/size/y range: constant + (length? files) - items-per-screen ] vv: slider 16x400 range [print vv/data num: vv/data - 1 show vx] ] Im my aproach si corrent, VID could support some func to count all above automatically by specifying list-face, block which goes for display, widest-item(row) ... Anyone? PS: aproach with 'constant is not correct ... have no further time to play with it right now .... :-) -pekr-