无法使用qml访问黑莓级联中listview项目组件内的Qsettings值

Question

我的主页上有一个listview，它有一个自定义的listitem组件。我在Qsettings变量中有一个值，我可以在主页中访问该变量，但我无法在自定义listitem组件中访问该变量。加载主页时，Qsetting数据日志打印在主页的“创建完成”上，但在customlistitemhomepage的onCreationCompleted中显示错误。下面是我的主页结构和customlistitemhomepage结构的示例代码。

Page {
    Container {
        layout: DockLayout {
        }
        ScrollView {
            id: homePageScroll
            Container {
                layout: DockLayout {
                }
                ListView {
                    id: contactListView
                    dataModel: contactsData
                    preferredHeight: homePageScroll.listHeight
                    overlapTouchPolicy: OverlapTouchPolicy.Allow
                    listItemComponents: [
                        ListItemComponent {
                            id: homeListComponent
                            type: "item"
                            CustomListItemHomePage {
                                id: listCell
                            }
                            //Some code
                        }
                    ]
                }
            }
        }

        onCreationCompleted: {
                 console.log("Clipboard value:"+_settings.getValueFor("clipBoard", "No Data")); //THIS PRINTS CORRECTLY
        }
    }
}

我也在CustomListItemHomePage.qml

中记录了相同的内容

 CustomListItemHomePage {
     onCreationCompleted: {
         console.log("Clipboard value:"+_settings.getValueFor("clipBoard", "No Data")); //THIS SHOWS ERROR CAN'T Find variable _settings
     }                             
 }

Answer 1

listItemComponents无法从Listview外部调用函数。因此，如果您想在CustomListItemHomePage.qml中调用QSettings函数，您可以这样做：

ListView {
    id: contactListView
    dataModel: contactsData
    preferredHeight: homePageScroll.listHeight
    overlapTouchPolicy: OverlapTouchPolicy.Allow
    listItemComponents: [
        ListItemComponent {
            id: homeListComponent
            type: "item"
            CustomListItemHomePage {
                id: listCell
                // Now you are able to call getClipboardValue() from ListItemComponent like 
                // listCell.ListItem.view.getClipboardValue() 
            }
            //Some code
        }
    ]
    function getClipboardValue() {
        return _settings.getValueFor("clipBoard", "No Data"));
    }
}