I want to create an accessible application. I want to show pdf files in TextBlock page by page but when I change the CurrentPage properties on EbookViewerViewModel the NVDA Screen Reader doesn't read It the text again. I thought if I set focus again the Screen Reader will read it, but doesn't. Can I solve this problem somehow?
The EbookViewerWindow.xaml contains this:
<Window x:Class="myproj.EbookViewerWindow"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
xmlns:local="clr-namespace:myproj"
mc:Ignorable="d"
Title="AEBCA - Könyv megjelenítő" Height="300" Width="300" Closed="Window_Closed" WindowStartupLocation="CenterScreen" KeyDown="Window_KeyDown">
<Grid>
<Grid.RowDefinitions>
<RowDefinition Height="40"></RowDefinition>
<RowDefinition></RowDefinition>
</Grid.RowDefinitions>
<Grid.ColumnDefinitions>
<ColumnDefinition></ColumnDefinition>
<ColumnDefinition></ColumnDefinition>
</Grid.ColumnDefinitions>
<TextBlock Grid.Row="0" Grid.Column="0" x:Name="AuthorTB" Text="{Binding Author}" AutomationProperties.Name="A könyv szerzője" AutomationProperties.HelpText="{Binding Author}" Focusable="True"></TextBlock>
<TextBlock Grid.Row="0" Grid.Column="1" x:Name="BookNameTB" Text="{Binding BookName}" AutomationProperties.Name="A könyv címe" AutomationProperties.HelpText="{Binding BookName}" Focusable="True"></TextBlock>
<DockPanel Grid.Row="1" Grid.ColumnSpan="2">
<TextBlock x:Name="CurrentPageTB" Text="{Binding CurrentPage}" AutomationProperties.Name="A könyv tartalma" AutomationProperties.HelpText="{Binding CurrentPage}" Focusable="True"></TextBlock>
<Label x:Name="help"></Label>
</DockPanel>
</Grid>
In the code behind I do this:
public partial class EbookViewerWindow : Window
{
EbookViewerViewModel vm;
int index = 0;
PdfReader pdfReader;
public EbookViewerWindow()
{
InitializeComponent();
vm = new EbookViewerViewModel();
DataContext = vm;
vm.Author = "Antoine de Saint-Exupéry";
vm.BookName = "A Kis Herceg";
AuthorTB.Focus();
string fileName = @"d:\pdf.pdf";
if (File.Exists(fileName))
{
pdfReader = new PdfReader(fileName);
NextPage(pdfReader);
}
}
private void Window_Closed(object sender, EventArgs e)
{
MainWindow mainWindow = new MainWindow();
mainWindow.Show();
}
private void Window_KeyDown(object sender, KeyEventArgs e)
{
if(e.Key == Key.Right)
{
NextPage(pdfReader);
CurrentPageTB.Focus();
e.Handled = true;
}
if(e.Key == Key.Left)
{
PreviousPage(pdfReader);
CurrentPageTB.Focus();
e.Handled = true;
}
}
private void NextPage(PdfReader pdfReader)
{
index++;
int pages = pdfReader.NumberOfPages;
ITextExtractionStrategy strategy = new SimpleTextExtractionStrategy();
string currentText = index.ToString() + ". oldal \n";
string temp = PdfTextExtractor.GetTextFromPage(pdfReader, index, strategy);
currentText += temp;
vm.CurrentPage = currentText;
}
private void PerviousPage(PdfReader pdfReader)
{
index--;
int pages = pdfReader.NumberOfPages;
ITextExtractionStrategy strategy = new SimpleTextExtractionStrategy();
string currentText = index.ToString() + ". oldal \n";
string temp = PdfTextExtractor.GetTextFromPage(pdfReader, index, strategy);
currentText += temp;
vm.CurrentPage = currentText;
}
}
}
My EbookViewerViewModel:
public class EbookViewerViewModel : BaseViewModel
{
private string currentPage;
public string BookName { get; set; }
public string Author { get; set; }
public string CurrentPage { get { return currentPage; } set { currentPage = value; OnPropertyChanged(); } }
}
