从普通类(.cs)访问控件
本文关键字:访问 控件 cs | 更新日期: 2023-09-27 18:26:41
我正在处理一个项目,需要访问一个普通类.cs中的标签。
不是来自MainWindow.xaml.cs!
MainWindow.xaml
:包含一个标签lblTag
。
Class.cs需要执行:
lblTag.Content = "Content";
我怎么能意识到呢?
我最终得到了InvalidOperationExceptions
。
Window1.xaml.cs:
public Window1()
{
InitializeComponent();
[...]
}
[...]
StreamElement se1;
StreamElement se2;
private void Window_Loaded(object sender, RoutedEventArgs e)
{
[...]
se1 = new StreamElement(this);
se2 = new StreamElement(this);
[...]
}
[...]
StreamElement.cs:
[...]
private Window1 _window;
[...]
public StreamElement(Window1 window)
{
_window = window;
}
[...]
//metaSync is called, whenever the station (it's a sort of internet radio recorder)
//changes the meta data
public void metaSync(int handle, int channle, int data, IntPtr user)
{
[...]
//Tags just gets the meta data from the file stream
Tags t = new Tags(_url, _stream);
t.getTags();
//throws InvalidOperationException - Already used in another thread
//_window.lblTag.Content = "Content" + t.title;
}
[...]
您需要在class:中引用MainWindow类的实例
public Class
{
private MainWindow window;
public Class(MainWindow mainWindow)
{
window = mainWindow;
}
public void MyMethod()
{
window.lblTag.Content = "Content";
}
}
您需要将对窗口实例的引用传递给类。从您的主窗口内,您身后的代码将调用:
var c = new Class(this);
c.MyMethod();
编辑:
您只能从同一个线程访问控件。如果您的类正在另一个线程中运行,则需要使用Dispatcher:
public void metaSync(int handle, int channle, int data, IntPtr user)
{
[...]
//Tags just gets the meta data from the file stream
Tags t = new Tags(_url, _stream);
t.getTags();
//throws InvalidOperationException - Already used in another thread
//_window.lblTag.Content = "Content" + t.title;
_window.lblTag.Dispatcher.BeginInvoke((Action)(() =>
{
_window.lblTag.Content = "Content" + t.title;
}));
}
编辑后,这一点现在似乎更清楚了。达米尔的答案应该是正确的。
只需在Class.cs上添加一个主窗口对象,并将主窗口的实例传递给类的构造函数。
在主窗口.xaml.cs 上
...
Class class = new Class(this);
...
关于Class.cs
...
MainWindow mWindow = null;
// constructor
public Class(MainWindow window)
{
mWindow = window;
}
private void Initialize()
{
window.lblTag.Content = "whateverobject";
}