How can I capture QKeySequence from QKeyEvent depending on current keyboard layout?

Question

I need to do this for configuring my application. I have QLineEdit field with reimplemented keyPressEvent method.

QKeyEvent *ke = ...
QString txt;

if(ke->         


        

Answer 1

What you might find very useful is the function QKeySequence().toString().

The following is a part of a code that I use to capture User Defined Shortcuts. With some modifications it can do whatever you need in your project. Hope it helps (sorry for the crapped identation):

if (event->type() == QEvent::KeyPress){ 
    QKeyEvent *keyEvent = static_cast<QKeyEvent*>(event); 

    int keyInt = keyEvent->key(); 
    Qt::Key key = static_cast<Qt::Key>(keyInt); 
    if(key == Qt::Key_unknown){ 
        qDebug() << "Unknown key from a macro probably"; 
        return; 
    } 
    // the user have clicked just and only the special keys Ctrl, Shift, Alt, Meta. 
    if(key == Qt::Key_Control || 
        key == Qt::Key_Shift || 
        key == Qt::Key_Alt || 
        key == Qt::Key_Meta)
    { 
        qDebug() << "Single click of special key: Ctrl, Shift, Alt or Meta"; 
        qDebug() << "New KeySequence:" << QKeySequence(keyInt).toString(QKeySequence::NativeText); 
        return; 
    } 

    // check for a combination of user clicks 
    Qt::KeyboardModifiers modifiers = keyEvent->modifiers(); 
    QString keyText = keyEvent->text(); 
    // if the keyText is empty than it's a special key like F1, F5, ... 
    qDebug() << "Pressed Key:" << keyText; 

    QList<Qt::Key> modifiersList; 
    if(modifiers & Qt::ShiftModifier) 
        keyInt += Qt::SHIFT; 
    if(modifiers & Qt::ControlModifier) 
        keyInt += Qt::CTRL; 
    if(modifiers & Qt::AltModifier) 
        keyInt += Qt::ALT; 
    if(modifiers & Qt::MetaModifier) 
        keyInt += Qt::META; 

    qDebug() << "New KeySequence:" << QKeySequence(keyInt).toString(QKeySequence::NativeText); 
}

Answer 2

You can assign keyboard shortcuts to actions.

Here are someways to do it.

actionName->setShortcut(QKeySequence::New); //for predefined shortcuts like new, close, open..

or you can define your own shortcut with this

actionName->setShortcut(QKeySequence("Ctrl+N")); // sets Ctrl + N for w.e the action does

In the first case qt automatically detects and assigns the appropriate shortcut for that particular action. In the second case, you can pick your own desired shortcut and type it as string. It automatically parses it and understands.

This avoids the need for using key captures for unnecessary purposes.

Answer 3

Prefer a standard seqence.

From the Keyboard Layout Issues:

As a result, both human-readable strings and hard-coded key codes can both be problematic to use when specifying a key sequence that can be used on a variety of different keyboard layouts. Only the use of standard shortcuts guarantees that the user will be able to use the shortcuts that the developer intended.

Answer 4

simpliest way is:

if(event->type() == QEvent::KeyPress)
{
    QKeyEvent *keyEvent = static_cast<QKeyEvent*>(event);
    qDebug() << "delete" << keyEvent->matches(QKeySequence::Delete);
    qDebug() << "copy" << keyEvent->matches(QKeySequence::Copy);
    qDebug() << "paste" << keyEvent->matches(QKeySequence::Paste);
}

Answer 5

If someone cares for the python version of the solution of Tihomir Dolapchiev above. I just translated it and it works great. Just posting for future reference.

class KeySequenceEdit(QtGui.QLineEdit):
    """
    This class is mainly inspired by
    http://stackoverflow.com/a/6665017

    """

    def __init__(self, keySequence, *args):
        super(KeySequenceEdit, self).__init__(*args)

        self.keySequence = keySequence
        self.setKeySequence(keySequence)

    def setKeySequence(self, keySequence):
        self.keySequence = keySequence
        self.setText(self.keySequence.toString(QtGui.QKeySequence.NativeText))


    def keyPressEvent(self, e):
        if e.type() == QtCore.QEvent.KeyPress:
            key = e.key()

            if key == QtCore.Qt.Key_unknown:
                warnings.warn("Unknown key from a macro probably")
                return

            # the user have clicked just and only the special keys Ctrl, Shift, Alt, Meta.
            if(key == QtCore.Qt.Key_Control or
            key == QtCore.Qt.Key_Shift or
            key == QtCore.Qt.Key_Alt or
            key == QtCore.Qt.Key_Meta):
                print("Single click of special key: Ctrl, Shift, Alt or Meta")
                print("New KeySequence:", QtGui.QKeySequence(key).toString(QtGui.QKeySequence.NativeText))
                return

            # check for a combination of user clicks
            modifiers = e.modifiers()
            keyText = e.text()
            # if the keyText is empty than it's a special key like F1, F5, ...
            print("Pressed Key:", keyText)

            if modifiers & QtCore.Qt.ShiftModifier:
                key += QtCore.Qt.SHIFT
            if modifiers & QtCore.Qt.ControlModifier:
                key += QtCore.Qt.CTRL
            if modifiers & QtCore.Qt.AltModifier:
                key += QtCore.Qt.ALT
            if modifiers & QtCore.Qt.MetaModifier:
                key += QtCore.Qt.META

            print("New KeySequence:", QtGui.QKeySequence(key).toString(QtGui.QKeySequence.NativeText))

            self.setKeySequence(QtGui.QKeySequence(key))

Answer 6

in case Qt users want it for Qml, here's how I did it.

There are however a few extra features that you might not want. I'll leave the code here and let users adapt.

TextField {
    Layout.fillWidth: true
    placeholderText: qsTr("Shortcut")
    text: shortcut
    onTextChanged: myModel.setPropertyAndUpdate(index, "shortcut", text, this)

    property var modifiers: ({ 0x02000000: "Shift", 0x04000000: "Ctrl", 0x08000000: "Alt", 0x10000000: "Meta", 0x20000000: "Keypad", 0x40000000: "GroupSwitch" })
    property var keys: ({
        0x01000000: "Escape", 0x01000001: "Tab", 0x01000002: "Backtab", 0x01000003: "Backspace", 0x01000004: "Return", 0x01000005: "Enter", 0x01000006: "Insert", 0x01000007: "Delete", 0x01000008: "Pause", 0x01000009: "Print", 0x0100000a: "SysReq", 0x0100000b: "Clear", 0x01000010: "Home", 0x01000011: "End", 0x01000012: "Left", 0x01000013: "Up", 0x01000014: "Right", 0x01000015: "Down", 0x01000016: "PageUp", 0x01000017: "PageDown", 0x01000020: "Shift", 0x01000021: "Control", 0x01000022: "Meta", 0x01000023: "Alt", 0x01001103: "AltGr", 0x01000024: "CapsLock", 0x01000025: "NumLock", 0x01000026: "ScrollLock", 0x01000030: "F1", 0x01000031: "F2", 0x01000032: "F3", 0x01000033: "F4", 0x01000034: "F5", 0x01000035: "F6", 0x01000036: "F7", 0x01000037: "F8", 0x01000038: "F9", 0x01000039: "F10", 0x0100003a: "F11", 0x0100003b: "F12", 0x0100003c: "F13", 0x0100003d: "F14", 0x0100003e: "F15", 0x0100003f: "F16", 0x01000040: "F17", 0x01000041: "F18", 0x01000042: "F19", 0x01000043: "F20", 0x01000044: "F21", 0x01000045: "F22", 0x01000046: "F23", 0x01000047: "F24", 0x01000048: "F25", 0x01000049: "F26", 0x0100004a: "F27", 0x0100004b: "F28", 0x0100004c: "F29", 0x0100004d: "F30", 0x0100004e: "F31", 0x0100004f: "F32", 0x01000050: "F33", 0x01000051: "F34", 0x01000052: "F35", 0x01000053: "Super_L", 0x01000054: "Super_R", 0x01000055: "Menu", 0x01000056: "Hyper_L", 0x01000057: "Hyper_R", 0x01000058: "Help", 0x01000059: "Direction_L", 0x01000060: "Direction_R", 0x20: "Space", 0x21: "Exclam", 0x22: "QuoteDbl", 0x23: "NumberSign", 0x24: "Dollar", 0x25: "Percent", 0x26: "Ampersand", 0x27: "Apostrophe", 0x28: "ParenLeft", 0x29: "ParenRight", 0x2a: "Asterisk", 0x2b: "Plus", 0x2c: "Comma", 0x2d: "Minus", 0x2e: "Period", 0x2f: "Slash", 0x30: "0", 0x31: "1", 0x32: "2", 0x33: "3", 0x34: "4", 0x35: "5", 0x36: "6", 0x37: "7", 0x38: "8", 0x39: "9", 0x3a: "Colon", 0x3b: "Semicolon", 0x3c: "Less", 0x3d: "Equal", 0x3e: "Greater", 0x3f: "Question", 0x40: "At", 0x41: "A", 0x42: "B", 0x43: "C", 0x44: "D", 0x45: "E", 0x46: "F", 0x47: "G", 0x48: "H", 0x49: "I", 0x4a: "J", 0x4b: "K", 0x4c: "L", 0x4d: "M", 0x4e: "N", 0x4f: "O", 0x50: "P", 0x51: "Q", 0x52: "R", 0x53: "S", 0x54: "T", 0x55: "U", 0x56: "V", 0x57: "W", 0x58: "X", 0x59: "Y", 0x5a: "Z", 0x5b: "BracketLeft", 0x5c: "Backslash", 0x5d: "BracketRight", 0x5e: "AsciiCircum", 0x5f: "Underscore", 0x60: "QuoteLeft", 0x7b: "BraceLeft", 0x7c: "Bar", 0x7d: "BraceRight", 0x7e: "AsciiTilde", 0x0a0: "nobreakspace", 0x0a1: "exclamdown", 0x0a2: "cent", 0x0a3: "sterling", 0x0a4: "currency", 0x0a5: "yen", 0x0a6: "brokenbar", 0x0a7: "section", 0x0a8: "diaeresis", 0x0a9: "copyright", 0x0aa: "ordfeminine", 0x0ab: "guillemotleft", 0x0ac: "notsign", 0x0ad: "hyphen", 0x0ae: "registered", 0x0af: "macron", 0x0b0: "degree", 0x0b1: "plusminus", 0x0b2: "twosuperior", 0x0b3: "threesuperior", 0x0b4: "acute", 0x0b5: "mu", 0x0b6: "paragraph", 0x0b7: "periodcentered", 0x0b8: "cedilla", 0x0b9: "onesuperior", 0x0ba: "masculine", 0x0bb: "guillemotright", 0x0bc: "onequarter", 0x0bd: "onehalf", 0x0be: "threequarters", 0x0bf: "questiondown", 0x0c0: "Agrave", 0x0c1: "Aacute", 0x0c2: "Acircumflex", 0x0c3: "Atilde", 0x0c4: "Adiaeresis", 0x0c5: "Aring", 0x0c6: "AE", 0x0c7: "Ccedilla", 0x0c8: "Egrave", 0x0c9: "Eacute", 0x0ca: "Ecircumflex", 0x0cb: "Ediaeresis", 0x0cc: "Igrave", 0x0cd: "Iacute", 0x0ce: "Icircumflex", 0x0cf: "Idiaeresis", 0x0d0: "ETH", 0x0d1: "Ntilde", 0x0d2: "Ograve", 0x0d3: "Oacute", 0x0d4: "Ocircumflex", 0x0d5: "Otilde", 0x0d6: "Odiaeresis", 0x0d7: "multiply", 0x0d8: "Ooblique", 0x0d9: "Ugrave", 0x0da: "Uacute", 0x0db: "Ucircumflex", 0x0dc: "Udiaeresis", 0x0dd: "Yacute", 0x0de: "THORN", 0x0df: "ssharp", 0x0f7: "division", 0x0ff: "ydiaeresis", 0x01001120: "Multi_key", 0x01001137: "Codeinput", 0x0100113c: "SingleCandidate", 0x0100113d: "MultipleCandidate", 0x0100113e: "PreviousCandidate", 0x0100117e: "Mode_switch", 0x01001121: "Kanji", 0x01001122: "Muhenkan", 0x01001123: "Henkan", 0x01001124: "Romaji", 0x01001125: "Hiragana", 0x01001126: "Katakana", 0x01001127: "Hiragana_Katakana", 0x01001128: "Zenkaku", 0x01001129: "Hankaku", 0x0100112a: "Zenkaku_Hankaku", 0x0100112b: "Touroku", 0x0100112c: "Massyo", 0x0100112d: "Kana_Lock", 0x0100112e: "Kana_Shift", 0x0100112f: "Eisu_Shift", 0x01001130: "Eisu_toggle", 0x01001131: "Hangul", 0x01001132: "Hangul_Start", 0x01001133: "Hangul_End", 0x01001134: "Hangul_Hanja", 0x01001135: "Hangul_Jamo", 0x01001136: "Hangul_Romaja", 0x01001138: "Hangul_Jeonja", 0x01001139: "Hangul_Banja", 0x0100113a: "Hangul_PreHanja", 0x0100113b: "Hangul_PostHanja", 0x0100113f: "Hangul_Special", 0x01001250: "Dead_Grave", 0x01001251: "Dead_Acute", 0x01001252: "Dead_Circumflex", 0x01001253: "Dead_Tilde", 0x01001254: "Dead_Macron", 0x01001255: "Dead_Breve", 0x01001256: "Dead_Abovedot", 0x01001257: "Dead_Diaeresis", 0x01001258: "Dead_Abovering", 0x01001259: "Dead_Doubleacute", 0x0100125a: "Dead_Caron", 0x0100125b: "Dead_Cedilla", 0x0100125c: "Dead_Ogonek", 0x0100125d: "Dead_Iota", 0x0100125e: "Dead_Voiced_Sound", 0x0100125f: "Dead_Semivoiced_Sound", 0x01001260: "Dead_Belowdot", 0x01001261: "Dead_Hook", 0x01001262: "Dead_Horn", 0x01001263: "Dead_Stroke", 0x01001264: "Dead_Abovecomma", 0x01001265: "Dead_Abovereversedcomma", 0x01001266: "Dead_Doublegrave", 0x01001267: "Dead_Belowring", 0x01001268: "Dead_Belowmacron", 0x01001269: "Dead_Belowcircumflex", 0x0100126a: "Dead_Belowtilde", 0x0100126b: "Dead_Belowbreve", 0x0100126c: "Dead_Belowdiaeresis", 0x0100126d: "Dead_Invertedbreve", 0x0100126e: "Dead_Belowcomma", 0x0100126f: "Dead_Currency", 0x01001280: "Dead_a", 0x01001281: "Dead_A", 0x01001282: "Dead_e", 0x01001283: "Dead_E", 0x01001284: "Dead_i", 0x01001285: "Dead_I", 0x01001286: "Dead_o", 0x01001287: "Dead_O", 0x01001288: "Dead_u", 0x01001289: "Dead_U", 0x0100128a: "Dead_Small_Schwa", 0x0100128b: "Dead_Capital_Schwa", 0x0100128c: "Dead_Greek", 0x01001290: "Dead_Lowline", 0x01001291: "Dead_Aboveverticalline", 0x01001292: "Dead_Belowverticalline", 0x01001293: "Dead_Longsolidusoverlay", 0x01000061: "Back", 0x01000062: "Forward", 0x01000063: "Stop", 0x01000064: "Refresh", 0x01000070: "VolumeDown", 0x01000071: "VolumeMute", 0x01000072: "VolumeUp", 0x01000073: "BassBoost", 0x01000074: "BassUp", 0x01000075: "BassDown", 0x01000076: "TrebleUp", 0x01000077: "TrebleDown", 0x01000080: "MediaPlay", 0x01000081: "MediaStop", 0x01000082: "MediaPrevious", 0x01000083: "MediaNext", 0x01000084: "MediaRecord", 0x1000085: "MediaPause", 0x1000086: "MediaTogglePlayPause", 0x01000090: "HomePage", 0x01000091: "Favorites", 0x01000092: "Search", 0x01000093: "Standby", 0x01000094: "OpenUrl", 0x010000a0: "LaunchMail", 0x010000a1: "LaunchMedia", 0x010000a2: "Launch0", 0x010000a3: "Launch1", 0x010000a4: "Launch2", 0x010000a5: "Launch3", 0x010000a6: "Launch4", 0x010000a7: "Launch5", 0x010000a8: "Launch6", 0x010000a9: "Launch7", 0x010000aa: "Launch8", 0x010000ab: "Launch9", 0x010000ac: "LaunchA", 0x010000ad: "LaunchB", 0x010000ae: "LaunchC", 0x010000af: "LaunchD", 0x010000b0: "LaunchE", 0x010000b1: "LaunchF", 0x0100010e: "LaunchG", 0x0100010f: "LaunchH", 0x010000b2: "MonBrightnessUp", 0x010000b3: "MonBrightnessDown", 0x010000b4: "KeyboardLightOnOff", 0x010000b5: "KeyboardBrightnessUp", 0x010000b6: "KeyboardBrightnessDown", 0x010000b7: "PowerOff", 0x010000b8: "WakeUp", 0x010000b9: "Eject", 0x010000ba: "ScreenSaver", 0x010000bb: "WWW", 0x010000bc: "Memo", 0x010000bd: "LightBulb", 0x010000be: "Shop", 0x010000bf: "History", 0x010000c0: "AddFavorite", 0x010000c1: "HotLinks", 0x010000c2: "BrightnessAdjust", 0x010000c3: "Finance", 0x010000c4: "Community", 0x010000c5: "AudioRewind", 0x010000c6: "BackForward", 0x010000c7: "ApplicationLeft", 0x010000c8: "ApplicationRight", 0x010000c9: "Book", 0x010000ca: "CD", 0x010000cb: "Calculator", 0x010000cc: "ToDoList", 0x010000cd: "ClearGrab", 0x010000ce: "Close", 0x010000cf: "Copy", 0x010000d0: "Cut", 0x010000d1: "Display", 0x010000d2: "DOS", 0x010000d3: "Documents", 0x010000d4: "Excel", 0x010000d5: "Explorer", 0x010000d6: "Game", 0x010000d7: "Go", 0x010000d8: "iTouch", 0x010000d9: "LogOff", 0x010000da: "Market", 0x010000db: "Meeting", 0x010000dc: "MenuKB", 0x010000dd: "MenuPB", 0x010000de: "MySites", 0x010000df: "News", 0x010000e0: "OfficeHome", 0x010000e1: "Option", 0x010000e2: "Paste", 0x010000e3: "Phone", 0x010000e4: "Calendar", 0x010000e5: "Reply", 0x010000e6: "Reload", 0x010000e7: "RotateWindows", 0x010000e8: "RotationPB", 0x010000e9: "RotationKB", 0x010000ea: "Save", 0x010000eb: "Send", 0x010000ec: "Spell", 0x010000ed: "SplitScreen", 0x010000ee: "Support", 0x010000ef: "TaskPane", 0x010000f0: "Terminal", 0x010000f1: "Tools", 0x010000f2: "Travel", 0x010000f3: "Video", 0x010000f4: "Word", 0x010000f5: "Xfer", 0x010000f6: "ZoomIn", 0x010000f7: "ZoomOut", 0x010000f8: "Away", 0x010000f9: "Messenger", 0x010000fa: "WebCam", 0x010000fb: "MailForward", 0x010000fc: "Pictures", 0x010000fd: "Music", 0x010000fe: "Battery", 0x010000ff: "Bluetooth", 0x01000100: "WLAN", 0x01000101: "UWB", 0x01000102: "AudioForward", 0x01000103: "AudioRepeat", 0x01000104: "AudioRandomPlay", 0x01000105: "Subtitle", 0x01000106: "AudioCycleTrack", 0x01000107: "Time", 0x01000108: "Hibernate", 0x01000109: "View", 0x0100010a: "TopMenu", 0x0100010b: "PowerDown", 0x0100010c: "Suspend", 0x0100010d: "ContrastAdjust", 0x01000110: "TouchpadToggle", 0x01000111: "TouchpadOn", 0x01000112: "TouchpadOff", 0x01000113: "MicMute", 0x01000114: "Red", 0x01000115: "Green", 0x01000116: "Yellow", 0x01000117: "Blue", 0x01000118: "ChannelUp", 0x01000119: "ChannelDown", 0x0100011a: "Guide", 0x0100011b: "Info", 0x0100011c: "Settings", 0x0100011d: "MicVolumeUp", 0x0100011e: "MicVolumeDown", 0x01000120: "New", 0x01000121: "Open", 0x01000122: "Find", 0x01000123: "Undo", 0x01000124: "Redo", 0x0100ffff: "MediaLast", 0x01ffffff: "unknown", 0x01100004: "Call", 0x01100020: "Camera", 0x01100021: "CameraFocus", 0x01100000: "Context1", 0x01100001: "Context2", 0x01100002: "Context3", 0x01100003: "Context4", 0x01100006: "Flip", 0x01100005: "Hangup", 0x01010002: "No", 0x01010000: "Select", 0x01010001: "Yes", 0x01100007: "ToggleCallHangup", 0x01100008: "VoiceDial", 0x01100009: "LastNumberRedial", 0x01020003: "Execute", 0x01020002: "Printer", 0x01020005: "Play", 0x01020004: "Sleep", 0x01020006: "Zoom", 0x0102000a: "Exit", 0x01020001: "Cancel"
    })
    property var modifierKeys: [Qt.Key_Alt, Qt.Key_Meta, Qt.Key_Control, Qt.Key_Shift, Qt.Key_NumLock, Qt.Key_Mode_switch]

    property bool lastWasNotModifier: false
    function parseKeyEvent(event, released) {
        if (!autoShortcut.checked)
            return

        if (!released && (event.key == Qt.Key_Backspace || event.key == Qt.Key_Delete) && event.modifiers == Qt.NoModifier) {
            text = ""
            event.accepted = true
            return
        }

        var isModifier = false
        modifierKeys.forEach(function(modifKey) {
            if (modifKey == event.key)
                isModifier = true
        })
        if (released && lastWasNotModifier) {
            event.accepted = true
            return
        }

        lastWasNotModifier = !isModifier

        if (event.key == Qt.Key_unknown) {
            console.log("Unknown key from a macro probably")
            //text = ""
            event.accepted = true
            return
        }

        var result = ""
        // var result = lastWasNotModifier ? text + "," : ""
        if (!(event.modifiers & Qt.NoModifier)) {
            for(var modifier in modifiers) {
                if (modifier & event.modifiers)
                    result += modifiers[modifier] + "+"
            }
        }

        if (!released && !isModifier) {
            result += keys[event.key]
        }
        if (text.endsWith('+')) {
            var t = text.split(',')
            text = t.slice(0, t.length - 1).join(',')
        }
        if (text) {
            if (text.endsWith(','))
                text = text + result
            else
                text = text + ',' + result
        }
        else {
            text = result
        }
        event.accepted = true
    }
    Keys.onPressed: parseKeyEvent(event, false)
    Keys.onReleased: parseKeyEvent(event, true)

    ToolButton {
        id: autoShortcut
        anchors {
            top: parent.top
            bottom: parent.bottom
            right: parent.right
            bottomMargin: 2
            topMargin: 2
            rightMargin: 2
        }
        text: qsTr("auto")
        checkable: true
        checked: true
        tooltip: qsTr("Wheter this line tries to create shortcut with you keypresses.\nIf disabled, you will be able to enter any key sequence as plain text")
    }
}