应该很容易
我是windows phone开发的新手,我想知道WP7中是否有类似时延的东西。
因为我想在图像完全加载后几秒钟后显示弹出窗口(比如5秒钟后,我需要自动打开弹出窗口),而无需单击任何按钮。
到目前为止,我是这样做的,但它会在图像加载后立即打开Popup。
Public Sub New()
InitializeComponent()
photoChooserTask = New PhotoChooserTask()
AddHandler photoChooserTask.Completed, AddressOf photoChooserTask_Completed
End Sub
Dim photoChooserTask As PhotoChooserTask
添加图像:
Private Sub AddImage_Click(sender As System.Object, e As System.EventArgs)
Try
photoChooserTask.Show()
Catch ex As System.InvalidOperationException
MessageBox.Show("An error occurred.")
End Try
End Sub
装载后图像:
Private Sub photoChooserTask_Completed(sender As Object, e As PhotoResult)
If e.TaskResult = TaskResult.OK Then
'Code to display the photo on the page in an image control named myImage.
Dim bmp As System.Windows.Media.Imaging.BitmapImage = New System.Windows.Media.Imaging.BitmapImage()
bmp.SetSource(e.ChosenPhoto)
myImage.Source = bmp
End If
Dim popup As New Popup()
popup.VerticalOffset = 140
Dim control As New PhonePage3()
popup.Child = control
popup.IsOpen = True
End Sub
End Sub
将Timer类用于任务非常简单(http://msdn.microsoft.com/en-us/library/system.threading.timer.aspx)。
创建计时器:
Timer myTimer = new Timer(OnTimerDone);
启动计时器以在5秒内(5000毫秒)获得回调:
myTimer.Change(5000, Timeout.Infinite);
定义回调函数:
private void OnTimerDone(object state)
{
// your code here
}
仅此而已:-)很抱歉使用C#代码,但我认为将其翻译成VB.