问题描述
我正在尝试将新对象插入到第 0 行的现有网格中(将剩余的行向下移动一格).有没有办法做到这一点?与 Log 类似，最后一项位于第一位.请注意，我不能使用 ListView，我已经在内容中有一个.另外，我更喜欢使用 Grid，因为我可以更好地构建它以进行演示等.完成的网格结构:
I'm trying to insert new object into existing Grid at row 0 (shifting the remaining rows one lower). Is there a way to do it? Similarly to Log, last item goes in first position. Note that I cannot use ListView, I already have one in the content. Also, I'd prefer to use Grid as I can structure it better for presentation wise etc. Finished grid structure:
> <Grid.RowDefinitions>
> <RowDefinition Height="*"/> </Grid.RowDefinitions>
> <Grid.ColumnDefinitions>
> <ColumnDefinition/>
> <ColumnDefinition/>
> <ColumnDefinition/>
</Grid.ColumnDefinitions>
> (existing Labels)
> <Label Text="1" Grid.Column="0" Grid.Row="0"/>
<Label Text="2" Grid.Column="0" Grid.Row="0"/>
> <Label Text="3", Grid.Column="0", Grid.Row="0"/>
> </>
我正在以编程方式生成网格，以填写上述结构(迭代列/行 nr)，然后尝试使用 Child 插入顶行:
I'm generating the grid programmatically, to fill out the above structure (iterate column / rows nr), then attempt to insert top row with Child:
MyGrid.RowDefinitions.Insert(0,newDefinition); // Insert new row
> MyGrid.Children.Add(new Label
> {
> Text = "original row",
> TextColor = Color.Black,
> LineBreakMode = Xamarin.Forms.LineBreakMode.WordWrap,
> HorizontalTextAlignment = TextAlignment.End,
> FontSize = Device.GetNamedSize(NamedSize.Small, typeof(Label)),
> }, 0, 0); //Column / Row
...
> MyGrid.RowDefinitions.Insert(0,newDefinition); // Insert new row
> at 0 row index
>
>
> MyGrid.Children.Add(new Label
> {
> Text = "new row",
> TextColor = Color.Black,
> LineBreakMode = Xamarin.Forms.LineBreakMode.WordWrap,
> HorizontalTextAlignment = TextAlignment.End,
> FontSize = Device.GetNamedSize(NamedSize.Small, typeof(Label)),
> }, 0, 0); //Column / Row
新行"将与原始行"重叠
"new row" will overlap "original row"
到目前为止，这就是我所做的.这仅适用于一次行移位，没有列移位.
So far, that's what I've done. This is only for one row shift,no column shift.
我无法通过 Grid Child 列/行获得
I could not get Grid Child column/row by
var left = Grid.Children[0].Left();//实验标志所以我将不得不进行更多迭代.
var left = Grid.Children[0].Left();//Experimental flag
So I will have to iterate more.
...添加带有标签的新行，0 列(默认情况下，Grid 有 1 列，1 个网格)，然后:
... add new Rows with Labels, 0 column (By default, Grid has 1 Column, 1 Grid), then:
Grid.RowDefinitions.Add(newRow);
for (int i = Grid.Children.Count -1 ; i >= 0; i--)
{
var child = > Grid.Children[i];
Grid.Children.RemoveAt(i);
Grid.Children.Add(child, 0, i +1);
}
Grid.Children.Add(SomeLabel, 0, 0);
推荐答案
你可以把你的Label放到List中，然后实现.
You can put you Label to List, then achieve it.
例如，如果我想在第一行第二列的地方添加一个标签，这里是运行GIF.
For example, If I want add a label in the first row and second Column place, here is running GIF.
这是我的网格布局.
<StackLayout Margin="10">
<Button Text="add" Clicked="Button_Clicked"></Button>
<Grid x:Name="MyGrid">
<Grid.RowDefinitions>
<RowDefinition Height="*"/>
</Grid.RowDefinitions>
<Grid.ColumnDefinitions>
<ColumnDefinition/>
<ColumnDefinition/>
<ColumnDefinition/>
</Grid.ColumnDefinitions>
</Grid>
</StackLayout>
这是我的布局背景代码.我在 List 中添加三个 Label，然后将 list 中的项目添加到 Grid.单击按钮时，在第 0 行第 1 列添加一个新的 Label，在 listview 中的位置为 1.
Here is my layout background code. I add three Labels in List, then add the items in list to the Grid. when click the Button, add a new Label to the row 0, column 1, the position in listview is 1.
public partial class MainPage : ContentPage
{
List<Label> labels;
public MainPage()
{
InitializeComponent();
labels = new List<Label>();
labels.Add(new Label
{
Text = "1",
LineBreakMode = Xamarin.Forms.LineBreakMode.WordWrap,
HorizontalTextAlignment = TextAlignment.End,
FontSize = Device.GetNamedSize(NamedSize.Small, typeof(Label)),
});
labels.Add(new Label
{
Text = "2",
LineBreakMode = Xamarin.Forms.LineBreakMode.WordWrap,
HorizontalTextAlignment = TextAlignment.End,
FontSize = Device.GetNamedSize(NamedSize.Small, typeof(Label)),
});
labels.Add(new Label
{
Text = "3",
LineBreakMode = Xamarin.Forms.LineBreakMode.WordWrap,
HorizontalTextAlignment = TextAlignment.End,
FontSize = Device.GetNamedSize(NamedSize.Small, typeof(Label)),
});
for (int i=0; i<labels.Count ;i++)
{
//If we set the three columns, we can set the Column and Row by i%3 i/3
MyGrid.Children.Add(labels[i],i%3,i/3);
}
}
private void Button_Clicked(object sender, EventArgs e)
{
// Remove the data in the original Gird
for (int i = 0; i < labels.Count; i++)
{
if (MyGrid.Children.Count>0)
{
var label = labels[i];
if (label != null)
{
MyGrid.Children.Remove(label) ;
}
}
}
// add label
var newLabel = new Label
{
Text = "new row",
TextColor = Color.Black,
LineBreakMode = Xamarin.Forms.LineBreakMode.WordWrap,
HorizontalTextAlignment = TextAlignment.End,
FontSize = Device.GetNamedSize(NamedSize.Small, typeof(Label)),
};
// If I want add a label in the first row and second Column place, I can add the new label to with `Insert` method in List.
labels.Insert(1,newLabel);
// re-add the list data to grid.
for (int i = 0; i < labels.Count; i++)
{
MyGrid.Children.Add(labels[i], i % 3, i / 3);
}
}
}
这篇关于Xamarin.Forms 将行插入网格并重新排列的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持编程学习网！