Enable / disable actions instead of buttons (to also enable / disable the associated key shortcuts). The actions 'View' and 'Edit' are only enabled if the selection consists of a file (not a directory)
Only trigger key strokes on key released
Initialize the buttons before showing the UI
Save the program state upon closing. Reload the configuration upon startup
Introduced class fr.ritaly.dualcommander.TabbedPane to remove redundant code
Simplified code. Ensure the tabbed panes have at least 1 tab
Set the focus to the newly created tab