我正在尝试将新对象插入到第0行的现有网格中(将其余行下移一行)。有办法吗?与日志类似,最后一项位于第一个位置。请注意,我不能使用ListView,我在内容中已经有一个。此外,我更喜欢使用网格,因为我可以更好地为演示等构建网格。完成的网格结构:
> <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),然后尝试插入顶部行与儿童:
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
编辑:到目前为止,这就是我所做的。这只适用于一行移位,没有列移位。
我无法按获取网格子列/行
var left=Grid。儿童[0]。左()//实验标志
,因此我将不得不进行更多的迭代。
... 添加标签为0列的新行(默认情况下,网格有1列,1个网格),然后:
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);
您可以将标签
放入列表
,然后实现它。
例如,如果我想在第一行和第二列位置添加一个标签,这里是运行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。我在列表中添加三个标签,然后将列表中的项目添加到网格中是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);
}
}
}
要将网格中的所有行移位一个,请使用Grid。GetRow()
和网格。SetRow()
方法可以像下面的示例代码一样使用。
foreach (var child in grid.Children)
{
var row = Grid.GetRow(child);
Grid.SetRow(child, row + 1);
}