Xamarin 窗体更改框架中的标签文本

Question

>我有一个问题。我创建了这个框架：

<Frame BackgroundColor="Black" BorderColor="DarkGray" CornerRadius="20" HeightRequest="40" Padding="10,0,10,0">
<Label Text="{Binding Name}" FontSize="20" TextColor="White" VerticalOptions="CenterAndExpand"
HorizontalOptions="CenterAndExpand"/>
<Frame.GestureRecognizers>
<TapGestureRecognizer Tapped="Category_Clicked" />
</Frame.GestureRecognizers>
</Frame>

在后面的代码中，我有这个事件：

List<string> selectedCategories = new List<string>();
private void Category_Clicked(object sender, EventArgs e)
{
Frame frame = (Frame)sender;
if (frame.BackgroundColor == Color.Black)
{
frame.BackgroundColor = Color.FromHex("#2196F3");
//Add label text to list
}
else
{
frame.BackgroundColor = Color.Black;
//Remove label text from list
}
}

但是我需要从框架内的标签访问文本。我该怎么做？

Answer 1

从FrameContent属性获取标签。

private void Frame_Tapped(object sender, EventArgs e)
{
Frame tappedFrame = (sender as Frame);
Label childLabel = (tappedFrame.Content as Label);
var resultText = childLabel.Text;
}

即使您不知道BindingContext的类型也可以工作.

Answer 2

<Frame BackgroundColor="Black" BorderColor="DarkGray" CornerRadius="20" HeightRequest="40" Padding="10,0,10,0">
<Label x:Name = "MyTxt" Text="{Binding Name}" FontSize="20" TextColor="White" VerticalOptions="CenterAndExpand"
HorizontalOptions="CenterAndExpand"/>
<Frame.GestureRecognizers>
<TapGestureRecognizer Tapped="Category_Clicked" />
</Frame.GestureRecognizers>

在代码隐藏中：

if (frame.BackgroundColor == Color.Black)
{
frame.BackgroundColor = Color.FromHex("#2196F3");
//Add label text to list
MyTxt.text = "Some Text";
}
else
{
frame.BackgroundColor = Color.Black;
//Remove label text from list
MyTxt.text = "";
}

Answer 3

使用BindingContext

Frame frame = (Frame)sender;
var item = (MyClassName)frame.BindingContext
var name = item.Name;