QML control type: menu

One 、 describe

Menu pop ups that can be used as context menus or pop-up menus .

When used as a context menu ：

MouseArea {
    anchors.fill: parent
    acceptedButtons: Qt.LeftButton | Qt.RightButton
    onClicked: {
        if (mouse.button === Qt.RightButton)
            contextMenu.popup()
    }
    onPressAndHold: {
        if (mouse.source === Qt.MouseEventNotSynthesized)
            contextMenu.popup()
    }

    Menu {
        id: contextMenu
        MenuItem { text: "Cut" }
        MenuItem { text: "Copy" }
        MenuItem { text: "Paste" }
    }
}

When used as a pop-up menu , The simplest way is to specify the required by using their respective properties x and y Coordinates to specify the location , And then call open() open a menu .

Button {
    id: fileButton
    text: "File"
    onClicked: menu.open()

    Menu {
        id: menu
        y: fileButton.height

        MenuItem {
            text: "New..."
        }
        MenuItem {
            text: "Open..."
        }
        MenuItem {
            text: "Save"
        }
    }
}

You can also do it in Menu Create a submenu in and declare Action object ：

Menu {
    Action { text: "Cut" }
    Action { text: "Copy" }
    Action { text: "Paste" }

    MenuSeparator { }

    Menu {
        title: "Find/Replace"
        Action { text: "Find Next" }
        Action { text: "Find Previous" }
        Action { text: "Replace" }
    }
}

By default , Submenus are cascaded on desktop platforms with available mouse cursors . Non cascading menus display one menu at a time , And focus on the parent menu .

Usually , Menu items are statically declared as sub items of the menu , but Menu Also provide API To dynamically add 、 Insert 、 Move and delete items .

Two 、 Attribute members

1、cascade : bool

Whether the menu cascades its submenus . The default value is platform specific .

Non cascading menus display one menu at a time , And focus on the parent menu .

Be careful ： Changing the value of this property when the menu is open is invalid .

2、[default] contentData : list<Object>

Content data list .

The list is contained in QML All objects declared as menu sub items in , And use addItem() and insertItem() Method to dynamically add or insert items .

Be careful ： And contentChildren Different ,contentData It does contain non visual QML object . Items are not reordered when inserted or moved .

 3、【 read-only 】contentModel : model

Model for displaying menu items .

Provide a content model for visualization purposes . It can be assigned as a model to content items that render menu content .

Menu {
    id: menu
    contentItem: ListView {
        model: menu.contentModel
    }
}

 4、【 read-only 】count : int

Number of projects .

5、currentIndex : int

Index of the currently highlighted item . Menu items can be highlighted by mouse over or keyboard navigation .

6、delegate : Component

Components for creating projects to render actions .

Menu {
    Action { text: "Cut" }
    Action { text: "Copy" }
    Action { text: "Paste" }
}

7、focus : bool

Whether the pop-up window needs focus . The default is false.

When the pop-up window actually gets the focus ,activeFocus Will be for true.

8、overlap : real

The number of pixels that the menu overlaps horizontally with its parent menu . The default is style specific .

This attribute is only valid if the menu is used as a cascading submenu .

It is invalid to change the value of the property when the menu is opened .

9、title : string

The title of the menu .

When the menu is a submenu , The title of the menu is usually displayed in the text of the menu item , And when it's in the menu bar , Is displayed in the text of the tool button .

3、 ... and 、 Member functions

 1、void popup(Item parent, real x, real y, MenuItem item = null)

      void popup(real x, real y, MenuItem item = null)

The specified position in the pop-up coordinate system x, y Open menu at , That is, the coordinates relative to its parent .

Menus can be selected to align with specific menu items .

    void popup(Item parent, point pos, MenuItem item = null)

    void popup(point pos, MenuItem item = null)

The specified position in the pop-up coordinate system pos Open menu at , That is, the coordinates relative to its parent .

Menus can be selected to align with specific menu items .

    void popup(Item parent, MenuItem item = null)

    void popup(MenuItem item = null)

Open the menu at the mouse cursor , Otherwise, put the menu in the center of its parent .

Menus can be selected to align with specific menu items .

2、Action actionAt(int index)

Returns... At index action , If the index is invalid or there is no operation at the specified index , Then return to null.

3、void addAction(Action action)

Add actions to the end of this menu .

4、void addItem(Item item)

Will be added to the end of the item list .

5、void addMenu(Menu menu)

Add the menu as a submenu to the end of this menu .

6、void dismiss()

Close all menus in the hierarchy to which this menu belongs .

Be careful ： With only closing the menu and its submenus close() Different ,dismiss() Close the entire hierarchy of the menu , Include parent menu .

7、void insertAction(int index, Action action)

Insert action at index . The index is located in all items in the menu .

8、void insertItem(int index, Item item)

Insert item at index .

9、void insertMenu(int index, Menu menu)

Insert a menu at the index as a submenu . The index is located in all items in the menu .

10、Item itemAt(int index)

Returns the item at the index , Returns if it does not exist null.

11、Menu menuAt(int index)

Return to the submenu at the index , If the index is invalid or there is no submenu at the specified index , Then return to null.

12、void moveItem(int from, int to)

Index from Items at move to index to.

13、void removeAction(Action action)

Delete and destroy the specified action .

14、void removeItem(Item item)

Remove and destroy the specified items .

15、void removeMenu(Menu menu)

Delete and destroy the specified menu .

16、Action takeAction(int index)

Delete and return the action at the index . The index is located in all items in the menu . Ownership of the action is transferred to the caller .

17、MenuItem takeItem(int index)

Delete and return the item at the index . Ownership of the item is transferred to the caller .

18、Menu takeMenu(int index)

Delete and return index Menu at . The index is located in all items in the menu .

Ownership of the menu is transferred to the caller .