Ubuntu – Custom Keyboard Layout to use H J K L as ARROWS not working properly


I set up my keyboard layout in /usr/share/X11/xkb/symbols/ to use the keys H J K L as arrows Left, Down, Up and Right as the third and fourth shift level. mostly I followed this post.
The Right Alt is my Alternative Characters Key.

While this customization will "basically" work, I can not select text by typing it in conjunction with SHIFT . For example, I can not select the text by pressing Alt Gr+Shift+H, as it would do with Shift+Left. But I can jump a whole word with Ctrl.

the HJKL are working exactly like the arrows in Firefox (with shift and Ctrl) but not on Gedit, Rhythmbox or Chrome, and possibly more…

Any ideas?
I'm using Ubuntu 14.04.

Edit:I am using a german keyboard with AltGr.
and the files are the fowllowing:

link to keyboard layout

(hope the link works now)

Best Answer

Go to xkb/types/iso9995 and edit the "THREE_LEVEL" type by adding

  preserve[Shift+LevelThree] = Shift;

so it looks like this

  partial default xkb_types "default" {

// A key type which can be used to implement
// an ISO9995-style level-three shift.

virtual_modifiers LevelThree;

type "THREE_LEVEL" {
    modifiers = Shift+LevelThree;
    map[None] = Level1;
    map[Shift] = Level2;
    map[LevelThree] = Level3;
    map[Shift+LevelThree] = Level3;
    preserve[Shift+LevelThree] = Shift;
    level_name[Level1] = "Base";
    level_name[Level2] = "Shift";
    level_name[Level3] = "Level3";

Then go to your symbols file and use this format

    key <AC06>  { type="THREE_LEVEL", [               h,               H,            Left ]     }; 
    key <AC07>  { type="THREE_LEVEL", [               j,               J,            Down ]     }; 
    key <AC08>  { type="THREE_LEVEL", [               k,               K,              Up ]     }; 
    key <AC09>  { type="THREE_LEVEL", [               l,               L,           Right ]     }; 

This is a related question from which I could figure out the answer to yours.