Rectangle with onEditingFinished

[Diracsbracket]

@gabor53
You cannot use declarative-style QML definitions inside JavaScript code directly. If you want to create a Rectangle inside your JS, then you must do it dynamically.

For example, declare a component somewhere

Component {
     id:  notificationMessage
     Text {
         //set positioning   + size properties here or at object creation time
     }   
}

Then:

onEditingFinished: {
      if (addName.text === "") {
           //Set a relevant visual item as parent, e.g. yourPageId
           var popup = notificationMessage.createObject(yourPageId, {text: "Enter the name."})
      }
}

Notes:
You may also create the component dynamically first using Qt.createComponent(), if you don't want to declare it inline in your QML code.

[gabor53]

Hi @Diracsbracket ,
I changed the code like this:

import VPlayApps 1.0
import QtQuick 2.0
import QtQuick 2.7

Page {
    title: qsTr("Add a Friend")

    Rectangle {
        id: root
        color: "lightblue"
        anchors.fill: parent

        Component {
            id: notificationMessage
            Rectangle {
                height: dp(20)
                color: "#be1717"
                width: dp(200)
                border.color: "darkred"
                border.width: 5
            }
        }

        Text {
            id: id
            text: "ID:"
            x: dp(30)
            y: dp(30)
            font.pixelSize: 45
        }

        AppTextField {
            id: addName
            anchors.top: id.bottom
            x: dp(30)
            anchors.margins: 30
            borderWidth: 3
            borderColor: "blue"
            backgroundColor: "lightgreen"
            clearsOnBeginEditing: true
            radius: 25
            cursorPosition: 0
            maximumLength: 85
            placeholderText: "Name:"
            placeholderColor: "darkblue"

            validator: RegExpValidator {
                regExp: /[A-z]/
            }

            onEditingFinished: {
                if (addName.text == "") {

                    var popup = notificationMessage.createObject(root, {
                                                                     text: "Enter the Friend's name."
                                                                 })
                }
            }
        }
    }
}

There is no error message and nothing happens when there is no character in the name field. What is still wrong with it?
Thank you.

[Diracsbracket]

Hi @gabor53
The component you created is a Rectangle, which has no text property ( I edited my previous message and replaced it by Text). Unfortunately, no error is generated when using a non-existing property in the argument list of a dynamically generated object.

If you want to avoid this, you could assign the property after the creation, like so:

var popup = notificationMessage.createObject(root)
popup.text = "Enter the Friend's name."

This would have generated an error, if popup were a Rectangle.

So in your case, you could use the following:

        Component {
            id: notificationMessage

            Rectangle {
                height: 20
                width: 200
                property alias text: msg.text

                Text {
                    id: msg
                    anchors.fill: parent
                 }
            }
        }

[gabor53]

@Diracsbracket
Thank you very much. This works great.
Just one more question:
I can use the notificationMessage component into a new file named Messages.qml. Is it possible to access in addaFriendP1.qml the notificationMessage component from Messages.qml? I tried whatever I found on the internet, but none of them worked. (I still want to use NotificationMessage in the if statement.
Thank you.

[Diracsbracket]

@gabor53
If you define your notification message in a separate QML file, then you shouldn't define it as a Component in that file. E.g. you would define Messages.qml as:

Rectangle {
                height: 20
                width: 200
                property alias text: msg.text

                Text {
                    id: msg
                    anchors.fill: parent
                 }
            }

Then, the dynamic object instantiation consists of two step:

1. Dynamically create a component, e.g. msgComponent from Messages.qml using Qt.CreateComponent()
2. Dynamically create the object from that component using msgComponent.createObject()

http://doc.qt.io/qt-5/qtqml-javascript-dynamicobjectcreation.html

I guess this rather tedious approach is due to the declarative nature of QML?
To save you the trouble, you could put this dynamic creation code inside a JS source file e.g. "code.js" which you would then import first like

import "code.js" as Js

The JS code could look as follows:

function createMsg(parent, args) {
      var msgComp = Qt.CreateComponent("Message.qml")
      var msg = msgComp.createObject(parent, args);
      return msg
}

If you rather not recreate the component all over again, you could also do something like:

var msgComp //global JS variable <-- usually not recommended though

function createMsg(parent, args) {
     if (msgComp!==undefined)
          msgComp = Qt.CreateComponent("Message.qml")

      var msg = msgComp.createObject(parent, args);
      return msg
}

Then in your QML code, simply call this function whenever you need as follows:

onEditingFinished: {
      if (addName.text === "") {
           var popup = Js.createMsg(yourPageId, {text: "Enter the name."})
      }
}

The possibilities are plenty!

[gabor53]

@Diracsbracket
Thank you for the detailed explanation. I chose to create the Js file (code.js) and it looks like this:

function createMsg(parent, args) {
    var msgComp = Qt.createComponent("Messages.qml")
    var msg = msg.Comp.createObject(parent, args)
    return msg
}

I changed the Messages.qml:

import QtQuick 2.0
import QtQuick 2.2
import VPlayApps 1.0

Rectangle {
    id: notificationSquare
    height: dp(30)
    anchors.top: addName.bottom
    anchors.left: addName.left
    anchors.topMargin: 20
    color: transparent
    width: dp(250)
    border.color: "#ff0000"
    border.width: 2
    property alias text: msg.text

    Text {
        id: msg
        font.bold: true
        horizontalAlignment: Text.AlignHCenter
        color: "red"
        font.pointSize: 20
        anchors.fill: notificationSquare
        anchors.horizontalCenter: notificationSquare.horizontalCenter
        anchors.verticalCenter: notificationSquare.verticalCenter
    }
}

AddaFriendP1.qml has id: add1 and the relevant code:

            onEditingFinished: {
                if (addName.text == "") {
                    var popup = Js.createMsg(add1, {
                                                 text: "Enter the Friend's name."
                                             })
                }
            }

I have no error message, but the warning message doesn't pop up either. Did I miss something?
Thank you for your help.

[Diracsbracket]

@gabor53 said in Rectangle with onEditingFinished:

var msg = msg.Comp.createObject(parent, args)

Must be

var msg = msgComp.createObject(parent, args)

Also, if a component is to be reusable, it is usually better to use parent properties to determine its size/anchoring rather than to hard-code some element's id.

Rectangle {
    id: notificationSquare
   ...
    anchors.top: parent.bottom //<- should work if parent does not have clip: true? //addName.bottom
    anchors.left: parent.left //addName.left
}

As mentioned in the comments above, anchoring the top of a child to the bottom property of its parent works if the parent's clip property is false (which is the default). If clip is set to true the child will not be visible with the above anchoring.

color: transparent

Did that not generate an error in your Application Output window?
There is no color transparent -> should be "transparent" between quotes.

[gabor53]

@Diracsbracket
There was no error message at all.

[Diracsbracket]

@gabor53 said in Rectangle with onEditingFinished:

There was no error message at all.

There was no error message at all in the Application output view when you tried to run it?

If those errors really are not reported, then you really should solve that problem first and find out why, but I suspect you may only have been looking at the Compile Output view or so.

[gabor53]

Hi @Diracsbracket ,
I fixed everything you highlighted and you are right, I focused on the compile output. In spite of the corrections it still doesn't display the rectangle and the text. Here are my changes:

    var msgComp = Qt.createComponent("Messages.qml")
    var msg = msgComp.createObject(parent, args)

       onEditingFinished: {
                if (addName.text === "") {
                    var popup = Js.createMsg(add1, {
                                                 text: "Enter the Friend's name."
                                             })

Rectangle {
    id: notificationSquare
    height: dp(30)
    anchors.top: parent.bottom
    anchors.left: parent.left
    anchors.topMargin: 20
    color: "transparent"

It seems correct but it is not working. Thank you for your help.

[Diracsbracket]

@gabor53
I think it's best if you try the following minimal test program, run it and compare it with what you have:

main.qml:

import QtQuick 2.11
import QtQuick.Window 2.11
import QtQuick.Controls 2.4

import "code.js" as Js

ApplicationWindow {
    id: window
    visible: true
    width: 640
    height: 480
    title: qsTr("Hello World")

Rectangle {
        id: root
        color: "lightblue"
        anchors.fill: parent
        focus: false

        Text {
            id: id
            text: "ID:"
            x: 30
            y: 30
            font.pointSize: 16
            focus: false
        }

        TextField {
            id: addName
            anchors.top: id.bottom
            x: 30
            anchors.margins: 30
            maximumLength: 85
            placeholderText: "Add Name"
            focus: true

            property Message msg

            onLengthChanged: {
                if (msg && length>0)
                    msg.destroy()
            }

            onEditingFinished: {
                if (length === 0)
                    msg = Js.createMsg(addName, {"text": "Enter the Friend's name."})
                else
                {
                    focus = false
                    console.debug("OK")
                }
            }
        }
    }

code.js

function createMsg(parent, args) {
    var msgComp = Qt.createComponent("Message.qml")
    var msg = msgComp.createObject(parent, args)
    return msg
}

[gabor53]

@Diracsbracket
Sorry for the late response. I needed to buy a new computer and I am still setting it up.

[Diracsbracket]

@gabor53 said in Rectangle with onEditingFinished:

I needed to buy a new computer and I am still setting it up.

I went through the same routine not so very long ago. Good luck!

[gabor53]

@Diracsbracket
Thank you. Now it seems to be working (both the new computer and the program).
I ended up with another issue:
To make Messages reusable I changed the anchoring from addName to parent. But addName is a child of addFriend1 so it is not aligned with addName. How can I tell the Rectangle from Messages in addFriend1 that the parent now is addName?
Thank you.

[Diracsbracket]

@gabor53
Don't you pass the desired parent object at object creation time? Like this:

function createMsg(parent, args) {
    var msgComp = Qt.createComponent("Message.qml")
    var msg = msgComp.createObject(parent, args)
    return msg
}

[gabor53]

@Diracsbracket
I do. And the rectangle and the text is in the the top left corner.

[Diracsbracket]

@gabor53
Show your result and your anchoring. They must be wrong.

Using the test code as above (with a slight modification to destroy the message) I get this:

 Rectangle {
        id: root
        color: "lightblue"
        anchors.fill: parent
        focus: false

        Text {
            id: id
            text: "ID:"
            x: 30
            y: 30
            font.pointSize: 16
            focus: false
        }

        TextField {
            id: addName
            anchors.top: id.bottom
            x: 30
            anchors.margins: 30
            maximumLength: 85
            placeholderText: "Add Name"
            focus: true
            //validator: RegExpValidator {regExp: /^[a-zA-Z ]{2,30}$/}

            property Message msg

            onLengthChanged: {
                if (msg && length>0)
                    msg.destroy()
            }

            onEditingFinished: {
                if (length === 0)
                    msg = Js.createMsg(addName, {"text": "Enter the Friend's name."})
                else
                {
                    focus = false
                    console.debug("OK")
                }
            }
        }
    }

where Messages.qml is

import QtQuick 2.11

Rectangle {
    id: notificationSquare
    height: 30
    anchors.top: parent.bottom
    anchors.left: parent.left
    anchors.topMargin: 20
    color: "transparent"
    width: 250
    border.color: "#ff0000"
    border.width: 2
    property alias text: msg.text

    function destroy() {
        this.destroy()
    }

    Text {
        id: msg
        font.bold: true
        horizontalAlignment: Text.AlignHCenter
        color: "red"
        font.pointSize: 12
        anchors.fill: parent
        anchors.horizontalCenter: parent.horizontalCenter
        anchors.verticalCenter: parent.verticalCenter
    }
}

[gabor53]

@Diracsbracket
I figured out what I did incorrectly. Somehow I deleted the root rectangle.
Thank you for your detailed explanations. I learnt a lot.