QML上拉加载逻辑

gistfile1.txt

    function once(fn, context) {
        var result
        return function () {
            if (fn) {
                result = fn.apply(context || this, arguments)
                fn = null
            }
            return result
        }
    }
    
    property var showNotification
    onDraggingVerticallyChanged: {
        showNotification = once(function () {
                notification.show("上拉加载")
            })
    }
    onContentYChanged: {
        if (draggingVertically && contentHeight > height
                && contentY - originY > contentHeight - height) {
            var dy = (contentY - originY) - (contentHeight - height)
            if (dy > 40 && model.count >= 100) {
                showNotification()
            }
        }
    }