QQuickWidget touch screen pen input - qt

I am trying to get pen or finger input from touch screen (Panasonic Toughbook). In the qml side i can not get click or tap input. I have tried the TapHandler with all pointer types and devices but it does not work. I can click with pen if i use QWidget (for example QPushButton) but qml does not work. I also check the events. I can take mouse events for QQuickWidget but does not work for qml.
import QtQuick 2.12
Item {
id: root
Rectangle {
anchors.fill: parent
color: "#bed3d4"
focus: true
TapHandler {
enabled: true
acceptedButtons: Qt.LeftButton
onTapped: {
console.log("Clicked")
}
}
TapHandler {
enabled: true
acceptedPointerTypes: PointerDevice.AllPointerTypes
acceptedDevices: PointerDevice.AllDevices
onTapped: {
console.log("Tapped")
}
}
}
}
In this code click works but tap doesn't.

I figured out to enable touch input in QQuickWidget you have to enable WA_AcceptTouchEvents flag with setAttribute(Qt::WA_AcceptTouchEvents).

Related

Disable context menu from qml in WebEngineView

I'm programming a WebEngineView and I want to disable its context menu.
For what I already found I have to call QWidget's setContexMenuPolicy.
Unfortunately, all help in the Net I can find shows how to do it from C++ code, while I need to do it all from my .qml file (I have no access to the c++ code).
I tried this.setContextMenuPolicy(...) from Component.onCompleted signal inside the WebEngineView, but to no success.
I found other way, which works for my case:
WebEngineView {
anchors.fill: parent
url: "https://www.example.com"
onContextMenuRequested: {
request.accepted = true
}
}
You can't just access QWidget functions in QML if they aren't forwarded via Q_PROPERTY. You should read The Property System.
My solution is a bit of a hack. It's using a MouseArea which consumes right mouse clicks, basically blocks all right clicks on the WebEngineView:
UPDATE!
import QtQuick 2.0
import QtQuick.Window 2.0
import QtWebEngine 1.0
Window {
width: 1024
height: 750
visible: true
WebEngineView {
anchors.fill: parent
url: "https://www.qt.io"
}
MouseArea {
anchors.fill: parent
acceptedButtons: Qt.LeftButton | Qt.MiddleButton | Qt.RightButton
onPressed: {
if (mouse.button === Qt.RightButton)
mouse.accepted = true
}
}
}

QML Popup: know how it was closed

I've a QML Popup that I can close by clicking outside of it or by pressing escape (hence default closing policy is fine).
However, I need to do different things if the popup is closed with escape (cancel a few things) or by clicking outside (commit the changes). I can't use Dialog, we don't want explicit buttons.
How can I reliably detect it ? So far, I've used a MouseArea to detect if the mouse is hover the Popup when it closes. The only issue is that is doesn't work if the user presses escape and it's mouse is outside the popup.
Popup
{
onAboutToHide: {
if(!ma.containsMouse)
{
}
}
contentItem: Text{
text: "hello"
}
MouseArea{
z:-1
id: ma
anchors.fill: parent
hoverEnabled:true
}
}
I tried to add
Keys.onEscapePressed:{
console.log('esc !')
}
to the popup, but then QML complains it's not an item.
you could change the default close policy and handle the Esc key press separately. The code will then look something like this:
Popup {
id: popup
onAboutToHide: {
if(!ma.containsMouse) {
console.log("click outside: commit the changes")
}
}
contentItem: Text {
text: "hello"
}
MouseArea {
z:-1
id: ma
anchors.fill: parent
hoverEnabled:true
}
closePolicy: Popup.CloseOnPressOutside
Shortcut {
sequence: "Esc"
onActivated: {
console.log("Esc: cancel a few things")
popup.close()
}
}
}

Qt Quick QML MouseArea autorepeat on press

Hopefully I'm not missing something obvious here.
I am writing an app and have made a zoom in button with an Image and a MouseArea. I need the button to repeat a method call after, say, every second to zoom in while holding the mouse button down. It isn't entirely obvious how to make this repeat. Right now I have:
Rectangle {
id:zoomInBtn
Image {
id: zoomInImg
anchors.centerIn: parent
fillMode: Image.PreserveAspectFit
source: zoomIn.pressed ? ":/img/zoom_in_sel" : ":/img/zoom_in_unsel"
}
MouseArea {
id: zoomIn
anchors.fill: parent
onPressed: { cameraController.zoomIn(0.5); }
}
I have also tried with
onPressAndHold: { cameraController.zoomIn(0.5); }
which does basically the same, although with a small delay as expected, but I need to repeat this action every second while the mouse button is held.
To perform the task you need you must use a Timer. the timer must remain active while the containsMouse is active. you must also enable triggeredOnStart to run immediately if the timer is activated.
Rectangle {
id:zoomInBtn
Image {
id: zoomInImg
anchors.centerIn: parent
fillMode: Image.PreserveAspectFit
source: zoomIn.pressed ? ":/img/zoom_in_sel" : ":/img/zoom_in_unsel"
}
MouseArea {
id: zoomIn
anchors.fill: parent
}
Timer {
id: timer
interval: 1000
repeat: true
triggeredOnStart: true
running: zoomIn.containsMouse
onTriggered: cameraController.zoomIn(0.5) //task
}
}
}

QML - MouseArea - propagating onPositionChanged

Is it possible to propagate a MouseArea's positionChanged event to an underlying one?
I've tried to set the mouse.accepted to false for any existing signal handler of the top-most MouseArea as well as setting the propagateComposedEvents to true. Neither of those worked (although I'm not surprised with the propagateComposedEvents not working since the documentation says it only relays events like clicked, doubleClicked and pressAndHold).
Depending on your structure you can always manually propagate the event by having your onPositionChanged handler call underlyingMouseArea.positionChanged(mouse) This should manually emit the signal in the underlying MouseArea. My only concern is that you might not be able to pass a MouseEvent object this way(never tried with anything other than a string). However, you can always perform this manual emit in C++ which definetly would not suffer from any type conversion issues.
Unless you need to handle position change events with multiple mouse areas simultaneously you could try reparent your top mouse area:
import QtQuick 2.2
import QtQuick.Layouts 1.1
Rectangle {
id: __root
color: "lightgreen"
width: 360
height: 360
Rectangle {
id: rect2
width: 100; height: 100
color: "cyan"
MouseArea {
parent: __root // set 'logical' parent
anchors.fill: rect2 // set 'visual' ancestor
hoverEnabled: true
onPositionChanged: {
console.log('mouse area 2 onPositionChanged');
}
}
}
MouseArea {
anchors.fill: parent
hoverEnabled: true
onPositionChanged: {
console.log('mouse area 1 onPositionChanged');
}
}
}
There is an unresolved bugreport.

How can I switch the focus for the pop-up window?

I encounter a problem which is that the pop-up window cannot get the focus when it is shown. I tried to use the activefocus function in main window, but it doesn't work. It is supposed that if I press the enter key, the pop-window will be closed. How can I get the focus for the pop-up window? Thanks.
...
GridView {
id:grid_main
anchors.fill: parent
focus: true
currentIndex: 0
model: FileModel{
id: myModel
folder: "c:\\folder"
nameFilters: ["*.mp4","*.jpg"]
}
highlight: Rectangle { width: 80; height: 80; color: "lightsteelblue" }
delegate: Item {
width: 100; height: 100
Text {
anchors { top: myIcon.bottom; horizontalCenter: parent.horizontalCenter }
text: fileName
}
MouseArea {
anchors.fill: parent
onClicked: {
parent.GridView.view.currentIndex = index
}
}
}
Keys.onPressed: { //pop up window
if (event.key == 16777220) {//enter
subWindow.show();
subWindow.forceActiveFocus();
event.accepted = true;
grid_main.focus = false;
}
}
}
Window {
id: subWindow
Keys.onPressed: {
if (event.key == 16777220) {//press enter
subWindow.close();
}
}
}
...
Let's start with some basics:
Keys.onPressed: { //pop up window
if (event.key == 16777220) {//enter
subWindow.show()
...
event.accepted = true
}
}
Not to mention how error-prone it is, just for the sake of readability, please don't hard-code enum values like 16777220. Qt provides Qt.Key_Return and Qt.Key_Enter (typically located on the keypad) and more conveniently, Keys.returnPressed and Keys.enterPressed signal handlers. These convenience handlers even automatically set event.accepted = true, so you can replace the signal handler with a lot simpler version:
Keys.onReturnPressed: {
subWindow.show()
...
}
Now, the next thing is to find the correct methods to call. First of all, the QML Window type does not have such method as forceActiveFocus(). If you pay some attention to the application output, you should see:
TypeError: Property 'forceActiveFocus' of object QQuickWindowQmlImpl(0x1a6253d9c50) is not a function
The documentation contains a list of available methods: Window QML type. You might want to try a combination of show() and requestActivate().
Keys.onReturnPressed: {
subWindow.show()
subWindow.requestActivate()
}
Then, you want to handle keys in the sub-window. Currently, you're trying to attach QML Keys to the Window. Again, if you pay attention to the application output, you should see:
Could not attach Keys property to: QQuickWindowQmlImpl(0x1ddb75d7fe0) is not an Item
Maybe it's just the simplified test-case, but you need to get these things right when you give a testcase, to avoid people focusing on wrong errors. Anyway, what you want to do is to create an item, request focus, and handle keys on it:
Window {
id: subWindow
Item {
focus: true
Keys.onReturnPressed: subWindow.close()
}
}
Finally, to put the pieces together, a working minimal testcase would look something like:
import QtQuick 2.9
import QtQuick.Window 2.2
Window {
id: window
width: 300
height: 300
visible: true
GridView {
focus: true
anchors.fill: parent
// ...
Keys.onReturnPressed: {
subWindow.show()
subWindow.requestActivate()
}
}
Window {
id: subWindow
Item {
focus: true
anchors.fill: parent
Keys.onReturnPressed: subWindow.close()
}
}
}
PS. Key events rely on focus being in where you expect it to be. This may not always be true, if the user tab-navigates focus elsewhere, for example. Consider using the Shortcut QML type for a more reliable way to close the popup.

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