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iOS keyboard doesn't activate when TextField receives focus



  • Is there something special that needs to happen? Some property that needs to be set? Some Xcode project setting? This seems to occur on all TextField instances for me on both iPhone and iPad.

    Thanks!



  • Hi @patrickkidd

    Can you please tell me Which Qt Version you are using ?

    As i use the TextField {} in my code it dose take the focus in iOS.

    • I am using QtQuick.Controls 2.2

    Can you check with below properties which might help you.

    Below is example from my code:

    import QtQuick.Controls 2.2
    
    ` ` ` `
                    TextField {
                        id: dataField
    
                        placeholderText: qsTr("Please Enter Data")
                        maximumLength: 18 // I restrict the input length.
                        Layout.fillWidth: true    // As i have it inside the ColumnLayout
                    }
    ` ` ` `
    
            Component.onCompleted: { // Do it for the root Component 
                dataField.forceActiveFocus();
            }
    

    All the best.


  • Moderators

    Hi @patrickkidd

    if your QML is inside a QQuickWidget or a QQuickView, than that is a well known, but infixed bug

    https://bugreports.qt.io/browse/QTBUG-63157

    My, very hackish, workaround for iOS is to create an offscreen QLineEdit that I set the focus on manually and forward the textChanged signal to QML.

    I hate it, but it works.



  • @J.Hilk said in iOS keyboard doesn't activate when TextField receives focus:

    Hi @patrickkidd

    if your QML is inside a QQuickWidget or a QQuickView, than that is a well known, but infixed bug

    https://bugreports.qt.io/browse/QTBUG-63157

    My, very hackish, workaround for iOS is to create an offscreen QLineEdit that I set the focus on manually and forward the textChanged signal to QML.

    I hate it, but it works.

    Do you have a code snippet? How do you detect the QML Item kb focus? Then how do you forward the kb events to the QML component?


  • Moderators

    @patrickkidd like I said, this code is nearly 2 years old, when I did my baby steps in QML x) so its convoluted

    TextInput{
                id:nameEdit
                anchors.fill: parent
                font.pixelSize: Manager.fontSize
    
                enabled: !root.reactToClicked
    
                activeFocusOnPress: true
    
                Keys.onReturnPressed:{
                    deselect()
                    Qt.inputMethod.hide();
                    parent.forceActiveFocus()
                }
    
                horizontalAlignment: Qt.AlignHCenter
                verticalAlignment: Qt.AlignVCenter
            }
    
            MouseArea{
                id:iosNameEdit
                anchors.fill: nameEdit
    
                visible: Qt.platform.os === "ios" && !root.reactToClicked
    
                property string uuid: Manager.newUuid()
                onClicked: {
                    Manager.initLineEdit(nameEdit.text,iosNameEdit.uuid,false);
                    root.moveUp()
                }
    
                Connections{
                    target: Manager
                    onCurrentTextChanged:{
                        if(uuid === iosNameEdit.uuid ) {
                            nameEdit.text = text
                        }
                    }
                    onEditingFinished:{
                        if(uuid === iosNameEdit.uuid ) {
                            root.moveDown()
                        }
                    }
                }
            }
    

    The relevant part of Manager instance:

    Q_INVOKABLE QString newUuid(){return QUuid::createUuid().toString();}
    
     Q_INVOKABLE void initLineEdit(const QString &text, const QString &uuid, bool useTimeRestiction) {
            if(iosLineEdit)
                iosLineEdit->initLineEdit(text,uuid,useTimeRestiction);
        }
    
    //Manager constructor
    iosLineEdit = new iOSLineEdit(qobject_cast<QWidget*>(parent));
        iosLineEdit->show();
        iosLineEdit->lower();
        connect(iosLineEdit, &iOSLineEdit::currentTextChanged, this, &Manager::currentTextChanged);
        connect(iosLineEdit, &iOSLineEdit::currentEditFinsihed, this, &Manager::editingFinished);
    
    //iosLineEdit.h
    class QRegExpValidator;
    class iOSLineEdit : public QLineEdit
    {
        Q_OBJECT
    public:
        explicit iOSLineEdit(QWidget *parent = nullptr);
    
    public slots:
        void initLineEdit(const QString &text, const QString &uuid, bool useTimeRestiction);
    
    signals:
        void currentTextChanged(const QString &uuid, const QString &text);
        void currentEditFinsihed(const QString &uuid);
    
    protected:
        QString m_Uuid;
        QRegExpValidator *m_Validator;
    };
    
    //iosLineEdit.cpp
    #include "ioslineedit.h"
    #include <QRegExpValidator>
    #include <QDebug>
    
    iOSLineEdit::iOSLineEdit(QWidget *parent) : QLineEdit (parent)
    {
        setMaximumSize(QSize(0,0));
        connect(this, &QLineEdit::textChanged, this, [=](const QString &text)->void{
            if( !m_Uuid.isEmpty()) {
                emit currentTextChanged(m_Uuid, text);
            }
        });
        connect(this, &QLineEdit::editingFinished, this, [=]()->void{
            if(!m_Uuid.isEmpty())
                emit currentEditFinsihed(m_Uuid);
            m_Uuid.clear();
            clear();
            setEnabled(false);
            hide();
        });
    
        m_Validator = new QRegExpValidator(QRegExp("/^(?:(?:([0-9]?\d|2[0-3]):)?([0-5]?\d):)?([0-5]?\d)$/"),this);
        lower();
        hide();
    }
    
    void iOSLineEdit::initLineEdit(const QString &text, const QString &uuid, bool useTimeRestiction)
    {
        qDebug() << Q_FUNC_INFO;
        m_Uuid.clear();
    
        if(useTimeRestiction) {
            setInputMask(QString("99:99:99"));
            setValidator(m_Validator);
        } else {
            setInputMask(QString());
            setValidator(nullptr);
        }
    
        setText(text);
    
        m_Uuid = uuid;
        setEnabled(true);
        show();
        setFocus();
    }
    
    

  • Moderators

    @patrickkidd
    Ignore the above post.

    I took the time to refine my original fix.

    You can find a working GitHub example here:
    https://github.com/DeiVadder/IosTextFieldWorkaround



  • @J.Hilk said in iOS keyboard doesn't activate when TextField receives focus:

    @patrickkidd
    Ignore the above post.

    I took the time to refine my original fix.

    You can find a working GitHub example here:
    https://github.com/DeiVadder/IosTextFieldWorkaround

    I tried this concept out in my app and it does work. Of course, there is quite a lot of features that need to be added, for example showing cursor position, allowing the selection of text, things like that.

    Let's hope this bug gets fixed.


  • Moderators

    @patrickkidd I think, once the keyboard is up, you could transfer the focus back to the textfield and the keyboard input would actually go to the textfield.

    But I haven't tested that thoroughly



  • @J.Hilk said in iOS keyboard doesn't activate when TextField receives focus:

    @patrickkidd I think, once the keyboard is up, you could transfer the focus back to the textfield and the keyboard input would actually go to the textfield.

    But I haven't tested that thoroughly

    Negative. Setting focus outside an accepted text input control is the event that hides the iOS keyboard again.


  • Moderators

    @patrickkidd yes, but textInput is an accepted text input control, just that the keyboard call event isn't forwarded outside the quickwidget.

    Thats at least what I read out of the bug report



  • @J.Hilk said in iOS keyboard doesn't activate when TextField receives focus:

    @patrickkidd yes, but textInput is an accepted text input control, just that the keyboard call event isn't forwarded outside the quickwidget.

    Thats at least what I read out of the bug report

    How exactly would you transfer focus back to the TextField? I tried setting the keyboard focus back to the TextInput item like the following pseudo-snippet and the keyboard was hidden again. Is that what you were thinking about?

    def beginFocus(self, text, textInputQQuickItem):
        quickWidget = QApplication.focusWidget()
        lineEdit.setFocus(Qt.MouseFocusReason)
        quickWidget.setFocus(Qt.MouseFocusReason)
        textInputQQuickItem.setFocus(True, Qt.MouseFocusReason)
    

  • Moderators

    @patrickkidd

    if you take my example and only change the content of IosLineEdit.qml

    to this

    import QtQuick 2.12
    import QtQuick.Controls 2.12
    
    import QLineEdit 1.0
    
    TextInput {
        id:root
        onEditingFinished: parent.forceActiveFocus()
    
        QLineEdit{
            id:backend
    
            onTextChanged: root.text = text
            onEditingFinished: root.parent.forceActiveFocus()
        }
    
        MouseArea{
            anchors.fill: parent
            visible: Qt.platform.os === "ios" && !root.activeFocus
    
            onClicked: {
                backend.init(root.text)
                shiftFocus.start()
            }
    
            Timer{
                id:shiftFocus
                interval: 10
                running: false
                repeat: false
                onTriggered: root.forceActiveFocus()
            }
        }
    }
    
    

    then the keyboard is called, focus shifted and text input has again all functionality

    have to change my repo I guess ;)



  • @J.Hilk said in iOS keyboard doesn't activate when TextField receives focus:

    @patrickkidd

    if you take my example and only change the content of IosLineEdit.qml

    
    then the keyboard is called, focus shifted and text input has again all functionality
    
    have to change my repo I guess ;)
    

    Calling QQuickItem::forceActiveFocus(Qt.MouseFocusReason) still does not help for me in my app. The keyboard does not appear for me in your example using the iOS Simulator either.

    Below is my own nearly complete drop-in solution that retains focus on the QLineEdit and has extra (and crucial) support for cursor positions and selection areas. It should be all the code you need. Note there is no mouse area, which causes problems in some cases where the TextInput is a child.

    class LineEditBackEnd(QLineEdit, Debug):
    
        def __init__(self, parent):
            super().__init__(parent)
            self.setMaximumSize(QSize(0, 0))
            self.move(-10, -10)
            self.lower()
            self.hide()
    
        # prevent a seg fault from calling `text` as property from qml                                                                                                                                              
        @pyqtSlot(result=str)
        def getText(self):
            return self.text()
    
        @pyqtSlot(str, int, int, int)
        def beginFocus(self, text, cursorPos, selectionStart, selectionEnd):
            if self.parent() is None:
                self.setParent(QApplication.activeWindow())
            self.blockSignals(True)
            self.setText(text)
            self.setCursorPosition(cursorPos)
            super().setSelection(selectionStart, selectionEnd-selectionStart)
            self.setFocus(Qt.MouseFocusReason)
            self.blockSignals(False)
            self.show()
            item.forceActiveFocus(Qt.MouseFocusReason)
    
        @pyqtSlot(str, int, int)
        def do_setSelection(self, text, start, end):
            self.blockSignals(True)
            if text != self.text():
                self.setText(text)
            super().setSelection(start, end-start)
            self.blockSignals(False)
    
        @pyqtSlot(int, int, int)
        def do_setCursorPosition(self, pos, start, end):
            self.blockSignals(True)
            super().setCursorPosition(pos)
            super().setSelection(start, end-start)
            self.blockSignals(False)
    
        @pyqtSlot(result=int)
        def getCursorPosition(self):
            return self.cursorPosition()
    
        @pyqtSlot(result=int)
        def selectionStart(self):
            return super().selectionStart()
    
        @pyqtSlot(result=int)
        def selectionEnd(self):
            return super().selectionEnd()
    
    qmlRegisterType(LineEditBackEnd, 'LineEditBackEnd', 1, 0, 'LineEditBackEnd')
    
    import QtQuick 2.12
    import QtQuick.Controls 2.5
    import QtQuick.Layouts 1.12
    import LineEditBackEnd 1.0
    
    // maybe a better text input that actually raises the kb on iOS                                                                                                                                                 
    
    TextInput {
    
        id: root
    
        LineEditBackEnd { id: backend }
    
        property bool syncing: false
        property bool ios: Qt.platform.os == 'ios'
    
        onFocusChanged: {
            if(ios && !syncing) {
                syncing = true
                backend.beginFocus(text, cursorPosition, selectionStart, selectionEnd)
                syncing = false
            }
        }
    
        onSelectionStartChanged: {
            if(ios && !syncing) {
                syncing = true
                backend.do_setSelection(text, selectionStart, selectionEnd)
                syncing = false
            }
        }
        onSelectionEndChanged: {
    	if(ios && !syncing) {
                syncing = true
                backend.do_setSelection(text, selectionStart, selectionEnd)
                syncing = false
    	}
        }
    
    
        onCursorPositionChanged: {
    	if(ios && !syncing) {
                syncing = true
                backend.do_setCursorPosition(cursorPosition, selectionStart, selectionEnd)
                syncing = false
    	}
        }
    
        Connections {
    	target: backend
    
    	onTextChanged: {
                if(ios && !syncing) {
    		syncing = true
    		root.text = backend.getText()
    		root.cursorPosition = backend.getCursorPosition()
                    syncing = false
                }
            }
    
            onCursorPositionChanged: function(_old, _new) {
                if(ios && !syncing) {
                    syncing = true
                    cursorPosition = _new
                    syncing = false
                }
            }
            onSelectionChanged: {
                if(ios && !syncing) {
                    syncing = true
                    select(backend.selectionStart(), backend.selectionEnd())
                    syncing = false
                }
            }
    
            onEditingFinished: root.parent.forceActiveFocus()
        }
    
    }
    


  • @J.Hilk Scratch that, your solution may have better support for cursors and selection areas after all. Could be an error on my end. I'll do some more checking.



  • @patrickkidd said in iOS keyboard doesn't activate when TextField receives focus:

    @J.Hilk Scratch that, your solution may have better support for cursors and selection areas after all. Could be an error on my end. I'll do some more checking.

    Hmm, I don't know. I wasn't able to port your solution into my project. The TextInput does not receive text events, or sometimes crashes when setting the text property, and does not support selection behavior. Not sure why. I guess I'll stick with mine which uses the default QtQuick selection behavior, until the Qt bug is fixed.


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