How to load custom QML controls into the QML Designer?

Cybrum

I am facing difficulty in importing my custom control into QML Designer. i.e. MyQMLControls 1.0 library has a BlueButton.
I want that BlueButton in QML Designer when I import MyQMLControls 1.0 in MyTestApp Project so that I can drag and drop the control .
Any help is appreciated.

Cybrum

I found a solution. I followed the below Steps:
1.Created a QtCreator Extension Plugin
2.In Pro file: Add
uri = mycompany.qmlcomponents
version =1.0

3.Added my CustomControl QML file.
4.Registered using qmlRegisterType
5.In qml dir:
module mycompany.qmlcomponents
plugin MyExtensionPlugin
classname MyExtensionPlugin
typeinfo mycompany.qmlcomponents
designersupported
5.Wrote the MetaInfo file (myextensionplugin.metainfo):
MetaInfo {
Type {
name: "mycompany.qmlcomponents.MyCustomItem"
icon: "images/customitem-icon.png"

        ItemLibraryEntry {
            name: "CustomItem"
            category: "My Extension - Items"
            libraryIcon: "images/customitem-icon.png"
            version: "1.0"
            requiredImport: "mycompany.qmlcomponents"

            Property {
                name: "itemItext"
                type: "binding"
                value: "qsTr(\"Button\")"
            }
        }
    }
}

6.Create a designer folder
7.Add following to designer.pri
QML_FILES +=
$$PWD/CustomItemSpecifics.qml
QML_FILES += $$PWD/myextensionplugin.metainfo
QML_FILES +=
$$PWD/images/customitem-icon.png
8.Build and install
9.Generate qmltypes: [You can also do this during qmake]
qmlplugindump mycompany.qmlcomponents1.0 > plugins.qmltypes
10.The controls will be available in the qml designer.

Check the unsupported properties for custom controls:
http://doc.qt.io/qtcreator/creator-quick-ui-forms.html