how to catch Spinbox event of change value in QML? - qt

Subj
I show my data on QML' Listview with delegated text, labels, and spinboxvalue elements of item. When user change the value of spinbox I need to know it and make some deals. But MouseArea works beyond of Spinbox, not on spinned buttons, onClicked event doesn't exists.
SpinBox {
id: goodsCountSpinBox
leftPadding: 1
rightPadding: 1
value: model.goodsCount
implicitWidth: 100
anchors.right: dataRow.right
MouseArea {
anchors.fill: parent
onClicked: {
listView.currentIndex = index; //Change the current selected item to the clicked item
console.log("SpinBox::MouseArea::onClicked")
}
}
By the way, and how to out current datetime in console log?
I found onValueChanged in examples but I don't find it in QML manuals.
SpinBox {
id: fontSizeSpinBox
activeFocusOnPress: false
implicitWidth: 50
value: 0
property bool valueGuard: true
onValueChanged: if (valueGuard) document.fontSize = value
}
I found to print current timestamp
Qt.formatTime(new Date()

If you want to just use the current value of the spinbox, just use its value property in a binding.
If you want to react to the value change, use the handler for the property's change signal, i.e. onValueChanged.

Related

QML - How to drag a ToolButton?

The QT documentation has this tutorial.
I initially followed it exactly, and it works. I then made two modifications:
I replaced the ListView with a GridView (that works without #2).
I attempted to add a ToolButton to my delegate inside the Rectangle "content" like so:
Rectangle {
id: content
ToolButton {
id: toolButton
icon.color = "transparent"
icon.source = "image://Loader/iconName"
}
Drag.active: dragArea.held
Drag.source: dragArea
Drag.hotSpot.x: width / 2
Drag.hotSpot.y: height / 2
}
This does not work, the ToolButton appears to be processing the mouse movements and not propagating the messages (I can click the button, but I can not drag it)? This is actually somewhat expected to be honest.
So that said, does anyone have a good way of dragging ToolButtons around? Or is it just accepted that you can't do that? I have tried various combinations of Rectangles and MouseAreas but I can't seem to do one without breaking the other (ie either the drag fails or the button fails).
You can move the MouseArea as a child of the ToolButton to manage the drag with pressAndHold, and propagate the click to keep the button behavior:
Rectangle {
id: content
ToolButton {
id: toolButton
// bind the visual state of the button to the MouseArea
background: Rectangle {
color: marea.pressed
? Qt.darker("blue")
: marea.containsMouse
? Qt.lighter("blue")
: "blue" // use your desired colors
}
MouseArea {
id: marea
property bool held: false
drag.target: held ? content : undefined
drag.axis: Drag.YAxis
anchors.fill: parent
hoverEnabled: true
onPressAndHold: held = true
onReleased: held = false
onClicked: toolButton.clicked() // propagate clicked event to the ToolButton
}
}
// ...
}

Open QML ComboBox drop down menu from the current item position

I have choose an item in combobox. Item's position is 300 for example. If I want to choose new element from combobox . Popup shows from beginning. I want to popup opened from current item position.
ComboBox {
id: control
model: ["First", "Second", "Third","MERHABA","NASILSIN","SELAM","IYIMISIN","DOSTUM","SUAN","BIR","DENEME YAPILIYOR"]
//width: 350
//font.pixelSize: 20
delegate: ItemDelegate {
width: 350
text: modelData
font.weight: control.currentIndex === index ? Font.DemiBold : Font.Normal
font.pixelSize: 30
highlighted: control.highlightedIndex == index
}
For QtQuick.Controls 2, There is a 'popup' property, so we can set the popup position with it's own property 'y', like this:
ComboBox {
model: ["First", "Second", "Third"]
delegate: ItemDelegate {
text: modelData
}
popup.y: y + height // popup just below ComboBox
}
The ComboBox will work the way you want it if the conditions allow for it, that is, if you have enough elements to fill the entire drop down list after the current index item it will show from that item rather than the beginning.
The stock ComboBox however doesn't seem to allow you to specify the drop down list height, so it will take significantly more elements than you have in your example. Or significantly taller elements.
Furthermore, if the current index is the last element, how do you imagine this will show? The list would show only the last element plus a whole bunch of nothing, which is not even possible, the last item cannot move up from the end of the list.
If you really want that behavior, you will have to implement your own combo box element from scratch.
I was facing the same issue and found out that if you place the popup onOpened, it works perfectly:
ComboBox {
id: yearDropdown
model: yearModel
onActivated: updateVisibleDate()
popup: Popup {
id: comboPopup
clip: true
contentItem: ListView {
id: listView
implicitHeight: contentHeight
model: yearDropdown.popup.visible ? yearDropdown.delegateModel : null
onModelChanged: if(model) positionViewAtIndex(yearDropdown.currentIndex, ListView.Center);
ScrollIndicator.vertical: ScrollIndicator { }
}
onOpened: {
x = yearDropdown.x //Set the position you want
y = yearDropdown.y + yearDropdown.implicitHeight //Set the position you want
}
}
}

ListView model function

I am just getting started in Qt, and trying to make function which operates ListView model's elements.
I have custom made button in "myButton.qml" which has states like "normal", "pressed", "selected", etc.
ListView is in "main.qml". Structure is like this:
ListView{
//...
model: nameModel
delegate: myButton {
//...
}
}
So here is my goal: this list of buttons should act like group of radiobuttons - only one can have selected state and selected state is when you press button. I think that I should have click handler and a function that calls on button click. Function should check the list of buttons and if one button was selected before function just changes its state to "Normal".
So I have no idea of how to write this func and where should I place it. I read Qt docs but still no idea.
A possible easy way to solve this problem is by exploiting ExclusiveGroup. As discussed in the documentation, support to this type can be added to any type:
It is possible to add support for ExclusiveGroup for an object or control. It should have a checked property, and either a checkedChanged, toggled(), or toggled(bool) signal. It also needs to be bound with ExclusiveGroup::bindCheckable() when its ExclusiveGroup typed property is set.
You can define an ExclusiveGroup at the ListView level and implement the required logic in the ListView delegate. By binding the delegate ExclusiveGroup property to the ExclusiveGroup of the ListView you should achieve what you want, without the need of a function that crawls the model.
Final toy example to demonstrate the usage:
import QtQuick 2.5
import QtQuick.Window 2.2
import QtQuick.Controls 1.4
Window {
id: root
visible: true
width: 200
height: 500
ListView {
anchors.fill: parent
model: 10
spacing: 20
ExclusiveGroup { id: ex } // the group for all the delegate
delegate: Rectangle {
id: delegate
width: ListView.view.width
height: 30
color: checked ? "yellow" : "steelblue"
// code to have exclusive behaviour
property bool checked: false
property ExclusiveGroup exclusiveGroup: ex
onExclusiveGroupChanged: {
if (exclusiveGroup)
exclusiveGroup.bindCheckable(delegate)
}
// mouse area to trigger the property change
MouseArea {
anchors.fill: parent
onClicked: checked = true
}
}
}
}

How to stop ListView for "jumping" when model is changed

What I need to do: I need to create a chat window using a ListView in QML that stores the chat-messages. I set listView.positionViewAtEnd() in order to follow the last messages. I disable positionViewAtEnd when I scroll upwards such that I can read the past messages without jumping at the end every time I receive a new message.
The problem: After scrolling up, every time I receive a new message it jumps at the beginning of list. To solve that I manage to store the contentY of the list and reset it every time onCountChanged handler is called (see the code below):
ListView {
id: messagesList
model: contact? contact.messages: []
delegate: delegate
anchors.fill: parent
anchors.bottomMargin: 20
height: parent.height
anchors.margins: 10
property int currentContentY
onMovementEnded: {
currentContentY = contentY
}
onCountChanged: {
contentY = currentContentY
}
onContentYChanged: {
console.log(".....contentY: " + contentY)
}
}
The problem is that even though I set the last contentY I had, before the model was changed, the list still jumps a bit (several pixels, not at the end or beginning) and it doesn't jump always. And when I go to the top of the list and print the contentY I get negative values. Theoretically, contentY at the beginning of the list should be 0.
Can somebody tell me what is going wrong? Or maybe suggest another solution to create my message list?
Than you in advance! :)
One possible solution schould be insert ListView into Flickable and disable interactive flag for ListView
Flickable {
id: fparent
anchors.fill: parent
anchors.bottomMargin: 20
anchors.margins: 10
interactive: true
clip: true
flickableDirection: Flickable.VerticalFlick
contentHeight: messagesList.height
ListView {
id: messagesList
width: parent.width
height: childrenRect.height
clip: true
model: contact? contact.messages: []
delegate: delegate
interactive: false
onCountChanged: {
fparents.returnToBounds();
}
}
}
Why not use onCountChanged slot in order to set the ListView at the end ?
onCountChanged: {
messagesList.positionViewAtEnd()
}

QML Gridview with InputText

I need a Listview with InputText on each row. Use case is a cart of items wherein qty can be changed for each row.
With the below code, Listview is rendering with a label and a text box alongside.
Issue is, all textboxes are going to have the same id, because of which, all textbox values are changing based on the last textbox value changed. Ex: If I enter 10 for the first item and 12 for the second item, even first item's qty changes to 12.
The onEnter is only for demonstration. It could be onFocusChanged going forward:
ListView {
id:list
model: fruitModel
x:10
y:10
width: parent.width-20
height: parent.height-20
clip:true
anchors.fill: parent
delegate: Row {
width: parent.width
height:30
Item
{
property variant myData: model
property alias value: text.text
Text {
id:text
width: parent.width
height: 30
text:name
}
InputText {
id: inp_box
text:qty
width:100
height:22
anchors.verticalCenterOffset: 15
anchors.horizontalCenterOffset:250
focus: true
onEnter: {
editQty(inp_box.text);
}
}
}
}
focus: true
snapMode: ListView.SnapOneItem
ScrollBar {
flickable: list
vertical: true
hideScrollBarsWhenStopped:false
}
}
You should extend your editQty function to take the index of edited entry in fruitModel as an additional parameter. The index of the current entry is available within the list view's delegate as index. The way you did it, editQty has no chance to know which entry to change.

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