When a user tries to open a BAM file into IGB there must be an associated BAM index file with the same name (before the extension) and it must be in the same directory as the BAM file.

A nice improvement would be to prompt the user to supply a BAM index file if IGB cannot find an associated BAM index file for the BAM file being opened. It could work like this:

1) The user tries to open a BAM file that does not contain an appropriate BAM index in the same directory.

2) IGB would realize there is no BAM index file to go with the BAM file so it would open a message that says something like "Cannot find the required index file for this BAM file. Would you like to locate the BAM index file?"

3) Then the user could click either a "No" button or a "Browse/Locate" button that would allow them to choose the BAM index file using the file explorer so that the BAM file would open appropriately.

*I'm also unsure how IGB should handle a case where a user tries to open a BAM file and then the user uses this new feature to select a BAM index file but they accidentally choose the wrong index file for the BAM file they want to open.