manifest: wait 200 ms of inactivity before applying manifest file filter
This improves the performance of the manifest filter when the number of files
Up until now the manifest file list was filtered each time that the user
typed a key on the filter box. If the user typed 5 characters on the filter box
the manifest file list would be filtered five times (once with the first
character, once with the first two characters, etc). When the number of files
is large, each filter operation can take longer than the time it takes for the
user to input a new character. The result is that the filter requests can pile
pile up and the filter box cann seem unresponsive.
This patch improves the situation by not triggering the filtering immediately.
Instead, each time a key is pressed on the filter box a filtering operation is
scheduled 200 ms in the future. If the user modifies the file filter box before
the actual filtering operation starts the previous scheduled filtering operation
is aborted, and a new one is scheduled 200 ms in the future.
The result is that if the user types several keys while a filter operation is
being performed, only the last filter operation will be executed.