private void stopScan_Click(object sender, RoutedEventArgs e)
{
backgroundService.stopService();
RackTextBox.Text = "";
BooksDataGrid.ItemsSource = null;
uiBook = null;
uiShelf = null;
}
/***
private void updateBookInformation(string str) //book list should be array list
{
//ctrl.Content = str;
//statusLabel.Content = str;
//statusLabel.Dispatcher.Invoke(() => { statusLabel.Content = str; });
}
* **/
/***
private void updateLocationInformation(string str)
{
//ctrl.Content = str;
//statusLabel.Content = str;
//statusLabel.Dispatcher.Invoke(() => { statusLabel.Content = str; });
}
* **/
private void updateUiBookInformation(Dictionary<string, string> scanItemList)
{
uiBook = new List<BookForDisplay>(); //共享的数据，用于在表格中显示图书信息，可能需要加锁
uiShelf = null; //共享的数据，用于显示层架数据，可能需要加锁
int count = 1;
lock (lockForUiBookAndUiShelf) //该部分一般被后台线程调用，更新了uiBook和uiShelf，需要加锁
{
foreach (KeyValuePair<string, string> item in scanItemList)
{
try
{
//先清除数据库状态位置所留下的信息！！
databaseStatusLabel.Dispatcher.Invoke(() => { databaseStatusLabel.Content = ""; });
if (item.Value.Equals("book"))
{
BookForDisplay oneBook = new BookForDisplay();
oneBook.id = count;
oneBook.bookName = bookdatabase.getBookNameByDecodedRFID(item.Key);
oneBook.scanCode = item.Key;
uiBook.Add(oneBook);
count = count + 1;
}
if (item.Value.Equals("shelf"))
{
String decodedShelfRFIDCode = item.Key;
uiShelf = shelfdatabase.getShelfLocation(decodedShelfRFIDCode);
String shelfLocationString = shelfdatabase.ShelfLocationInformationToString(uiShelf);
RackTextBox.Dispatcher.Invoke(() =>
{
RackTextBox.Text = shelfLocationString;
});
}
}
catch (DataBaseQueryException)
{
databaseStatusLabel.Dispatcher.Invoke(() => { databaseStatusLabel.Content = "查不到该条目信息！"; });
continue;//某一个条码可能在数据库中找不到，但不能因此中断程序
}
catch(DataBaseConnectException)
{
databaseStatusLabel.Dispatcher.Invoke(() => { databaseStatusLabel.Content = "数据库连接失败！"; });
}
catch(Exception)
{
continue;
}
}
//当用户点击停止扫描时，状态位被置false，但后台线程可能还要运行，在这期间还会刷新主界面
//因此当检查到该位为false立即停止更新ui，该程序片段必须放在刷新BookUI以前
if (backgroundService.serviceStatus == false)
{
BooksDataGrid.Dispatcher.Invoke(() =>
{
RackTextBox.Text = "";
BooksDataGrid.ItemsSource = null;
});
return;
}
BooksDataGrid.Dispatcher.Invoke(() =>
{
//BooksDataGrid.ItemsSource = null;
BooksDataGrid.ItemsSource = uiBook;
//实现自动滚到最后一行
BooksDataGrid.ScrollIntoView(BooksDataGrid.Items[BooksDataGrid.Items.Count - 1]);
});
}
}
