如何从Golang Fyne容器中删除对象

如何解决如何从Golang Fyne容器中删除对象

我正在研究需要动态添加和删除gui元素的GUI应用程序，我想知道是否存在一种从golang fyne容器中删除元素的方法。在下面的示例代码中，我创建了容器并动态添加了元素，现在我希望能够删除这些元素而不是隐藏它们。（我尝试的一个“解决方案”是创建新容器，填充它并重置窗口内容，但是它闪烁并且我不喜欢它。）

package main

import (
    "fyne.io/fyne"
    "fyne.io/fyne/app"
    "fyne.io/fyne/canvas"
    "fyne.io/fyne/layout"
    "fyne.io/fyne/widget"
    "image/color"
    "strconv"
    "time"
)

type Input struct {
    Id       string
    ThumbUrl string
}

func (input Input) GetContainer() *fyne.Container {
    thumbImg := canvas.NewText("There",color.White)
    group := widget.NewGroup(input.Id,thumbImg)
    ret := fyne.NewContainerWithLayout(layout.NewVBoxLayout(),group)
    return ret
}

type Segment struct {
    Id           string
    Inputs       []Input
    InputsColumn *fyne.Container
}

func (seg *Segment) GetSegment() fyne.CanvasObject {
    first := true
    var inputsColumn *fyne.Container
    for _,in := range seg.Inputs {
        if first {
            inputsColumn = fyne.NewContainerWithLayout(layout.NewGridLayout(1),in.GetContainer())
            first = false
        } else {
            inputsColumn.Addobject(in.GetContainer())
        }
    }
    seg.InputsColumn = inputsColumn

    ret := fyne.NewContainerWithLayout(layout.NewHBoxLayout(),seg.InputsColumn)
    return ret
}

func (seg *Segment) AddInput(input Input) {
    seg.InputsColumn.Addobject(input.GetContainer())
}

var (
    segment1 = Segment{
        Id: "VSEG_1",Inputs: []Input{
            {
                Id:       "VIN_HDMI1",ThumbUrl: "thumbIN.png",},{
                Id:       "VIN_SDI1",{
                Id:       "VIN_SDVOE1",}
)

func main() {
    myApp := app.New()
    myWindow := myApp.NewWindow("Container")
    segmentLayout := segment1.GetSegment()
    lay := fyne.NewContainerWithLayout(layout.NewHBoxLayout(),segmentLayout)

    myWindow.SetContent(lay)
    go changeContent(myWindow)
    myWindow.ShowAndRun()
}

func changeContent(win fyne.Window) {
    for i := 0; i < 3; i++ {
        time.Sleep(time.Second * 2)
        newInput := Input{
            Id:       "Added_ID_" + strconv.Itoa(i),}
        segment1.AddInput(newInput)
        segment1.InputsColumn.Refresh()

    }
    for i := 0; i < 3; i++ {
        time.Sleep(time.Second * 2)
        // Remove the objects instead of hiding
        segment1.InputsColumn.Objects[i].Hide()
        segment1.InputsColumn.Refresh()
    }
    segment1.InputsColumn.Refresh()

}

解决方法

使用fyne.Container，您可以直接更改Objects字段。例如，您可以使用以下命令删除添加的第一项：

l1 := widget.NewLabel("first")
l2 := widget.NewLabel("second")
c := fyne.NewContainer(l1,l2)
log.Println(len(c.Objects)) // 2

c.Objects = c.Objects[:1]
c.Refresh() // ensures UI reflects the change
log.Println(len(c.Objects)) // 1