Add MenuBar

[joseivanlopez]

This PR replaces #93.

Trello

https://trello.com/c/4GtDpmMo/

Overview

This adds a MenuBar widget to the NCurses UI.

For more details, see the main PR for this feature:

/~https://github.com/libyui/libyui/pull/169

Travis Build Failure

This doesn't build because the image used by Travis does not yet contain the libyui with the new features. This is expected.

Related PRs

• libyui: /~https://github.com/libyui/libyui/pull/169
• Qt UI: New Widget: MenuBar (Qt UI Implementation) libyui-qt#130
• UI Interpreter: New Widget: MenuBar (UI Interpreter Part) yast/yast-ycp-ui-bindings#53

Proposed Solution

There is a new class NCMenuBar that manages the top menu list. This class has the following responsibilities:

• To draw the menus.
• To select the next/previous menu.
• To skip over disabled menus.
• To open a popup with the selected menu (using a NCPopupMenu).
• To handle shortcuts for the menus.
• Cyclic navigation between options.
• When a menu is open, key left opens the previous menu (if any).
• When a menu is open, key right opens the next menu (if any and current item has no submenu).
• Esc to close the menu.

The class NCPopupMenu was extended, gaining these responsibilities:

• To skip over disabled options.
• Cyclic navigation between options.
• Auto-select the first enabled item when the first item is disabled.

The NCPopupMenu internally uses a NCTable, and this could have some drawbacks:

• How to include check- and radio-boxes in the submenu?

Pending Tasks:

• Shortcuts for top level menus.
• Represent a separator with a line?

NOTE: Pending tasks will come in another PR. We want to merge this now to synchronize SO version of all libyui related packages.

[shundhammer]

LGTM for an intermediate merge so we can move forward with this.

[shundhammer]

approved

[anaselli]

I would add on pending task also:

• pressing space or return should open menus not doing nothing

And yes please add something to show separator, leaving an empty line is not looking like a separator

[anaselli]

In a first try I also changed "..." to show that there is a sub menu with ">" maybe you can think to do something like that pretty better looking, I gave up just thinking to R2L languages

I like the menu selection and move left and right that i haven't implemented so well.

Please follow also discussion here