Beispiel #1
0
/* static */ PRUint32
KeymapWrapper::ComputeDOMKeyCode(const GdkEventKey* aGdkKeyEvent)
{
    // If the keyval indicates it's a modifier key, we should use unshifted
    // key's modifier keyval.
    guint keyval = aGdkKeyEvent->keyval;
    if (GetModifierForGDKKeyval(keyval)) {
        // But if the keyval without modifiers isn't a modifier key, we
        // shouldn't use it.  E.g., Japanese keyboard layout's
        // Shift + Eisu-Toggle key is CapsLock.  This is an actual rare case,
        // Windows uses different keycode for a physical key for different
        // shift key state.
        guint keyvalWithoutModifier = GetGDKKeyvalWithoutModifier(aGdkKeyEvent);
        if (GetModifierForGDKKeyval(keyvalWithoutModifier)) {
            keyval = keyvalWithoutModifier;
        }
        return GetDOMKeyCodeFromKeyPairs(keyval);
    }

    // If the key isn't printable, let's look at the key pairs.
    PRUint32 charCode = GetCharCodeFor(aGdkKeyEvent);
    if (!charCode) {
        // Always use unshifted keycode for the non-printable key.
        // XXX It might be better to decide DOM keycode from all keyvals of
        //     the hardware keycode.  However, I think that it's too excessive.
        guint keyvalWithoutModifier = GetGDKKeyvalWithoutModifier(aGdkKeyEvent);
        PRUint32 DOMKeyCode = GetDOMKeyCodeFromKeyPairs(keyvalWithoutModifier);
        if (!DOMKeyCode) {
            // If the unshifted keyval couldn't be mapped to a DOM keycode,
            // we should fallback to legacy logic, so, we should recompute with
            // the keyval with aGdkKeyEvent.
            DOMKeyCode = GetDOMKeyCodeFromKeyPairs(keyval);
        }
        return DOMKeyCode;
    }

    // printable numpad keys should be resolved here.
    switch (keyval) {
        case GDK_KP_Multiply:  return NS_VK_MULTIPLY;
        case GDK_KP_Add:       return NS_VK_ADD;
        case GDK_KP_Separator: return NS_VK_SEPARATOR;
        case GDK_KP_Subtract:  return NS_VK_SUBTRACT;
        case GDK_KP_Decimal:   return NS_VK_DECIMAL;
        case GDK_KP_Divide:    return NS_VK_DIVIDE;
        case GDK_KP_0:         return NS_VK_NUMPAD0;
        case GDK_KP_1:         return NS_VK_NUMPAD1;
        case GDK_KP_2:         return NS_VK_NUMPAD2;
        case GDK_KP_3:         return NS_VK_NUMPAD3;
        case GDK_KP_4:         return NS_VK_NUMPAD4;
        case GDK_KP_5:         return NS_VK_NUMPAD5;
        case GDK_KP_6:         return NS_VK_NUMPAD6;
        case GDK_KP_7:         return NS_VK_NUMPAD7;
        case GDK_KP_8:         return NS_VK_NUMPAD8;
        case GDK_KP_9:         return NS_VK_NUMPAD9;
    }

    KeymapWrapper* keymapWrapper = GetInstance();

    // Ignore all modifier state except NumLock.
    guint baseState =
        (aGdkKeyEvent->state & keymapWrapper->GetModifierMask(NUM_LOCK));

    // Basically, we should use unmodified character for deciding our keyCode.
    PRUint32 unmodifiedChar =
        keymapWrapper->GetCharCodeFor(aGdkKeyEvent, baseState,
                                      aGdkKeyEvent->group);
    if (IsBasicLatinLetterOrNumeral(unmodifiedChar)) {
        // If the unmodified character is an ASCII alphabet or an ASCII
        // numeric, it's the best hint for deciding our keyCode.
        return WidgetUtils::ComputeKeyCodeFromChar(unmodifiedChar);
    }

    // If the unmodified character is not an ASCII character, that means we
    // couldn't find the hint. We should reset it.
    if (unmodifiedChar > 0x7F) {
        unmodifiedChar = 0;
    }

    // Retry with shifted keycode.
    guint shiftState = (baseState | keymapWrapper->GetModifierMask(SHIFT));
    PRUint32 shiftedChar =
        keymapWrapper->GetCharCodeFor(aGdkKeyEvent, shiftState,
                                      aGdkKeyEvent->group);
    if (IsBasicLatinLetterOrNumeral(shiftedChar)) {
        // A shifted character can be an ASCII alphabet on Hebrew keyboard
        // layout. And also shifted character can be an ASCII numeric on
        // AZERTY keyboad layout.  Then, it's a good hint for deciding our
        // keyCode.
        return WidgetUtils::ComputeKeyCodeFromChar(shiftedChar);
    }

    // If the shifted unmodified character isn't an ASCII character, we should
    // discard it too.
    if (shiftedChar > 0x7F) {
        shiftedChar = 0;
    }

    // If current keyboard layout isn't ASCII alphabet inputtable layout,
    // look for ASCII alphabet inputtable keyboard layout.  If the key
    // inputs an ASCII alphabet or an ASCII numeric, we should use it
    // for deciding our keyCode.
    // Note that it's important not to use alternative keyboard layout for ASCII
    // alphabet inputabble keyboard layout because the keycode for the key with
    // alternative keyboard layout may conflict with another key on current
    // keyboard layout.
    if (!keymapWrapper->IsLatinGroup(aGdkKeyEvent->group)) {
        gint minGroup = keymapWrapper->GetFirstLatinGroup();
        if (minGroup >= 0) {
            PRUint32 unmodCharLatin =
                keymapWrapper->GetCharCodeFor(aGdkKeyEvent, baseState,
                                              minGroup);
            if (IsBasicLatinLetterOrNumeral(unmodCharLatin)) {
                // If the unmodified character is an ASCII alphabet or
                // an ASCII numeric, we should use it for the keyCode.
                return WidgetUtils::ComputeKeyCodeFromChar(unmodCharLatin);
            }
            PRUint32 shiftedCharLatin =
                keymapWrapper->GetCharCodeFor(aGdkKeyEvent, shiftState,
                                              minGroup);
            if (IsBasicLatinLetterOrNumeral(shiftedCharLatin)) {
                // If the shifted character is an ASCII alphabet or an ASCII
                // numeric, we should use it for the keyCode.
                return WidgetUtils::ComputeKeyCodeFromChar(shiftedCharLatin);
            }
        }
    }

    // If unmodified character is in ASCII range, use it.  Otherwise, use
    // shifted character.
    if (!unmodifiedChar && !shiftedChar) {
        return 0;
    }
    return WidgetUtils::ComputeKeyCodeFromChar(
                unmodifiedChar ? unmodifiedChar : shiftedChar);
}