I want to set the activeFocus for a FocusScope by clicking anywhere within an Item.
Is there a way to achieve this without having a MouseArea over the entire Item? Because it would have to overlay all elements within the Item, making them unclickable.
I'm pretty new to QtQuick/QML and have troubles understanding how to properly implement FocusScopes. I've read about propagating click signals, but couldn't get it to work.
Assuming I have something like this (no FocusScopes for readability):
Rectangle
{
id: outerRectangle
width: 1000
height: 1000
// various controls in here
Rectangle
{
id: innerRectangle
anchors.centerIn: parent
width: 200
height: 200
// even more controls in here
}
}
I want the outerRectangle to get the activeFocus when I click anywhere on the outerRectangle and vice-versa for the innerRectangle. But all controls on both Rectangles still have to work properly.
How can I achieve this?
Surround your Item with FocusScope:
FocusScope {
Item {
focus: true
}
}
See Qt Doc
Related
I want to display a large amount of content, for example, a grid of multiple images inside a window that is smaller than the content, similar to a geographical map but instead of a map, I want my own components as the "map". For this minimal working example, let's take for the content a grid of images with a total size of 1000x1000 with a window into this content of only 300x300.
I have tried 2 different approaches, but I will only go into detail of the first approach as that is the one that got me closest to my desired result:
I have tried the Flickable component but the content cannot be moved outside the predefined bounds, making the user unable to move the view in order to display all the parts of the content. So the simplest solution that I'm thinking about now is if I could remove these bounds from the Flickable component, but how?
I have also tried the Map component but it requires a "plugin" and I was unable to figure out how to use this component with my own content of an image grid.
The content that I want to show is something this
Grid {
columns: 5
spacing: 2
Repeater {
model: ListModel {
ListElement {
path: 'test1'
}
ListElement {
path: 'test2'
}
// ...
ListElement {
path: 'test25'
}
}
Rectangle {
width: 200
height: 200
Image {
anchors.fill: parent
source: 'file:' + path
}
}
}
}
I tried, putting this inside the Flickable like this
Flickable {
anchors.centerIn: parent
width: 300
height: 300
contentWidth: 1000
contentHeight: 1000
clip: true
// INSERT CUSTOM GRID COMPONENT HERE
}
This results in a 300x300 view inside the content as expected, but once you start to flick through the content to view different parts of it, you are stopped by the bounds preventing you from seeing anything outside these bounds. You can see it while dragging but once you release the view of the content is reset to these bounds.
So how do I remove these bounds? (Or is there a different component more suitable for my application?)
Here is a gif that shows how the content can be dragged passed the bounds, but once released it will only go up to the bounds and not further
I found the issue, I set the contentWidth and contentHeight of the Flickable incorrectly, this example works fine. The contentWidth and contentHeight determine the bounds in which you can flick.
I want to have two list views followed by one another in a big ScrollView, say because they have slightly different delegates. So a layout is like this:
Unfortunately ListView type is also a flickable, so it doesn't present all its content in a flat list suitable for having inside a scroll view.
So how do I do this with Qt Quick views?
I've tried a trick: I can resize list views like this:
ListView {
id: list1
height: contentHeight + spacing * count
model: superModel
delegate: delegate1
}
Unfortunately, aside from being a dirty hack and leaving an unneccesary flickable grabbing my clicks, it doesn't really work: content just doesn't fit as there are still top and bottom margins I don't know the value of.
You should use a ColumnLayout with two Repeater's in a ScrollView (or Flickable if you like)
ScrollView {
contentWidth: width //maybe you don't need this
ColumnLayout {
width: parent.width //maybe you don't need this
Repeater {
model: superModel1
delegate: delegate1
}
Repeater {
model: superModel2
delegate: delegate2
}
}
}
Since you didn't show the delegate, you might need minor tweaking of implicitHeight and/or implicitWidth.
I have search high and low in the documentation but have not found anything regarding this. Is there anyway that an QML element I have created can get notified if one of it's children needs to be redrawn due to changes to it. Will the item send a signal or an event that the parent can connect/listen to. Preferably it would be emitted when the item is marked "dirty" and should be rendered again, but a signal like onPropertyChange would work also.
Example
MyQmlItem {
Rectangle {
width: 50; height: 60
color: "blue"
Text {
text: "hello world"
}
}
}
If some code e.g changes the color of the Rectangle I would like the MyQmlItem to be notified about this change.
FWIIW i managed to find an acceptable solution to above. I added a boolean property "isDirty" to the MyQmlItem class, this emits a signal when it is set to true. Then each child needs to set this if it makes changes that needs redrawing, the QML above then becomes
MyQmlItem {
id: "topItem"
Rectangle {
width: 50; height: 60
color: "blue"
Text {
text: "hello world"
onTextChange: {
topItem.isDirty = true;
}
}
}
not perfect, but good enough
Qt/QML question. Using Qt 5.7.
Take the following simple QML program that displays a red rectangle and a blue rectangle aligned vertically. Click handlers for both rectangles attempt to change the color of the parent host window. But with a subtle difference. The red rectangle references the host window directly by it's id (rootWindow). The blue click handler changes color via a parent reference.
The former case works fine. The latter case does not work. It seems like the root window is treated specially and isn't directly part of the parent/child hierarchy, even if the Rectangles are logically nested in the code that way.
Can someone explain the rule around this?
import QtQuick 2.7
import QtQuick.Window 2.2
Window {
visible: true
width: 640
height: 480
title: qsTr("Hello World")
id: rootWindow
color: "#ffffee"
Rectangle {
id: rect1; width: 50; height: 50; color:"red"
MouseArea {
anchors.fill: parent;
onClicked: {
print("rect1 clicked");
rootWindow.color = "green"; // works fine
}
}
}
Rectangle {
id: rect2; width: 50; height: 50; color:"blue"
anchors.top: rect1.bottom
MouseArea {
anchors.fill: parent;
onClicked: {
print("rect2 clicked");
rect2.parent.color = "pink"; // does not work
}
}
}
}
If you add the following line to the onClicked handler, you'll see that its parent isn't the Window:
print(rect2.parent)
Output:
qml: QQuickRootItem(0x18b18147bc0)
This is explained not-so-visibly in the documentation for Window:
If you assign an Item to the data list, it becomes a child of the Window's contentItem, so that it appears inside the window. The item's parent will be the window's contentItem, which is the root of the Item ownership tree within that Window.
The window itself isn't an item, so it uses contentItem instead so that child items can have a parent.
However, in Qt 5.7, Window got an attached property that can be used to access the window of an item:
rect2.Window.window.color = "pink";
Whichever item comes before the Window.window part will be the item that the attached property is used on. You could use it on any item in this scene (e.g. the MouseArea), as they all belong to the same window.
Note that attached properties create a QObject-derived object for each unique item they're used on, so be mindful of how you use them, especially in items that are created in very large numbers.
I created a ListView, which displays a couple of pages of content defined by the user (plain text). The page displayed is a delegate. Only one page is visible at a time. I decided to use it to get snapping to one item, in the same way the iOS' launcher works. The user simply flicks between the pages. (this is to be used on touch screens)
I need to have the index of the currently displayed page for some operation. currentIndex of the ListView always stays == 0. How can I get it?
For those who prefer code:
ListView
{
onCurrentIndexChanged: console.log(currentIndex) // this gets called only once - at startup
delegate: Column
{
// The page displayed, only one page at a time
}
}
Thanks
There are many ways to get the index of current item that is displayed in the screen. If you can get the x-y coordinate of current page, you can use indexAt method in ListView.
And in each delegate, you can find the index using index role within the scope of the delegate. The index is like a role you declared in your model, and is automatically assigned by ListView. For example,
ListView
{
delegate: Column
{
property int indexOfThisDelegate: index
//...
}
}
The index role is introduced here:
A special index role containing the index of the item in the model is also available to the delegate. Note this index is set to -1 if the item is removed from the model...
Another way is to explicitly assign value to the currentItem property in ListView, so the view can scroll by itself. Here is an simple example in Qt documentation, which is similar to your application.
I know this is quite old but I had the same problem and spend some time trying to find a way to get currentIndex that would work for me. In my case sometimes I need to change the width of my ListView so I have to recalculte currentIndex manualy every time I resize it.
But I found a highlightRangeMode property. When it's set to ListView.StrictlyEnforceRange then currentIndex is always updated automaticly and contains correct index of the currently visible item.
ListView {
highlightRangeMode: ListView.StrictlyEnforceRange
// ...
}
You can do like that:
QModelIndex index =this->indexAt(event->pos());
this ->setCurrentIndex(index);
You can use attached properties of ListView class (ListView). They are attached to each instance of the delegate.
See ListView.isCurrentItem or ListView.view example:
ListView {
width: 180; height: 200
Component {
id: contactsDelegate
Rectangle {
id: wrapper
width: 180
height: contactInfo.height
color: ListView.isCurrentItem ? "black" : "red"
Text {
id: contactInfo
text: name + ": " + number
color: wrapper.ListView.isCurrentItem ? "red" : "black"
}
}
}
model: ContactModel {}
delegate: contactsDelegate
focus: true
}