Consider the example below (requires Qt 5.7):
import QtQuick 2.6
import QtQuick.Layouts 1.1
import QtQuick.Window 2.2
import QtQuick.Controls 2.0
ApplicationWindow {
width: 400
height: 200
visible: true
onActiveFocusItemChanged: print("activeFocusItem", activeFocusItem)
header: ToolBar {
RowLayout {
focus: false
implicitWidth: children[0].implicitWidth
implicitHeight: children[0].implicitHeight
ToolButton {
text: qsTr("File")
onClicked: fileMenu.open()
Menu {
id: fileMenu
y: parent.height
MenuItem {
text: qsTr("New")
}
MenuItem {
text: qsTr("open")
}
MenuItem {
text: qsTr("Close")
}
}
}
}
}
FocusScope {
id: focusScope
focus: true
anchors.fill: parent
property bool toggled: false
onToggledChanged: print("toggled", toggled)
Keys.onPressed: {
if (event.modifiers === Qt.AltModifier) {
focusScope.toggled = true;
}
}
Keys.onReleased: {
if ((event.modifiers === Qt.AltModifier || event.key ===
Qt.Key_Alt) && !event.isAutoRepeat) {
focusScope.toggled = false;
}
}
RowLayout {
anchors.centerIn: parent
Button {
id: penButton
text: qsTr("Pen")
highlighted: !focusScope.toggled
}
Button {
id: eyedropperButton
text: qsTr("Eyedropper")
highlighted: focusScope.toggled
}
}
}
}
The idea is that holding the Alt key down will toggle between two "modes". The
mode is indicated by a highlighted button.
Try switching between the buttons. Now open the menu by clicking the "File"
button. The menu will receive focus and the focus scope will lose it. If you
then close the menu and try to switch between the buttons again, it won't work
because the focus scope never regained focus (the root item now has it). This
is explained here [1]:
"When a QML Item explicitly relinquishes focus (by setting its focus property
to false while it has active focus), the system does not automatically select
another type to receive focus. That is, it is possible for there to be no
currently active focus."
I'm not sure if "explicitly relinquishes focus" is exactly what's happening
here, though. The FocusScope loses focus because something else was open
temporarily. So now the developer has no other option than to listen to e.g.
the menu visibility changes and explicitly set focus on the FocusScope
accordingly. That's pretty gross if you ask me. I think we can do better.
Specifically, I think that we should remember the last focused item, and give
that focus, rather than give it to the root item. The question is, would it be
an acceptable change for Qt 5? I'd assume that users are already working around
this anyway, and so the fix wouldn't hurt.
[1] http://doc.qt.io/qt-5/qtquick-input-focus.html
_______________________________________________
Development mailing list
[email protected]
http://lists.qt-project.org/mailman/listinfo/development
