try to access qml global variable, but it reports error - qt

Question

my code
AppDelegate.js for global variables
.pragma library
var appDelegate= {}
MyApp.js
Qt.include("AppDelegate.js")
function AppDelegate(){
}
AppDelegate.prototype.doSomething=function() {
console.log("vvvvvvvvvvvvv")
}
AppDelegate.prototype.doSomething1=function() {
console.log("AAAAAAAAAAAAAA")
}
//-------------------------------------------------------
function initApp(){
appDelegate=new AppDelegate()
appDelegate.doSomething()
appDelegate.doSomething1()
}
MyApp.qml
import QtQuick 2.2
import QtQuick.Controls 1.2
import "MyApp.js" as MyApp
ApplicationWindow {
visible: true
title: "System Dialogs Gallery"
width: 580
height: 480
TabView {
anchors.fill: parent
anchors.margins: 8
Tab {
id: controlPage
title: "File"
FileDialogs { }
}
}
Component.onCompleted: {
MyApp.initApp()
}
}
it works well and output is
qml: vvvvvvvvvvvvv
qml: AAAAAAAAAAAAAA
but if I call from other .js .qml file
ColorDialogs.js
Qt.include("AppDelegate.js")
function doit(){
appDelegate.doSomething1()
}
ColorDialogs.qml
import QtQuick 2.2
import QtQuick.Controls 1.2
import QtQuick.Dialogs 1.1
import "ColorDialogs.js" as ColorDialogs
Item {
Component.onCompleted: {
ColorDialogs.doit()
}
}
it reports error:
ColorDialogs.js: : TypeError: Property 'doSomething1' of object [object Object] is not a function
Your comment welcome
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