Question

I have a WebBrowser element in a page, to which I would like to add a back and forward buttons, and have those buttons disabled when there’s nothing to go back to and nothing to go forward to.

In Cocoa, the UIWebView has methods to easily check that: canGoBack and canGoForward, and you have goBack and goForward methods available (along with reload etc..)

Android has the exact same method names for achieving the same.

I see those methods are available in .Net 4 and 3.5 SP1.

I’ve found some references about using javascript commands in Silverlight but I find this very cumbersome, plus there’s no way to detect if there’s anything in the history (unless of course I manage this myself)

Surely, there’s something a tad more advanced in Windows Phone ..

Answer 1

Here is how I ended up doing it.

This assumes you have set a backButton and forwardButton; the status of these buttons will be updated accordingly depending on where you are in the navigation stack.

webView is the WebBrowser object

List<Uri> HistoryStack;
int HistoryStack_Index;
bool fromHistory;

// Constructor
public HelpView()
{
    InitializeComponent();
    HistoryStack = new List<Uri>();
    HistoryStack_Index = 0;
    fromHistory = false;
    webView.Navigated += new EventHandler<System.Windows.Navigation.NavigationEventArgs>(WebView_Navigated);
    UpdateNavButtons();
}

private void backButton_Click(object sender, RoutedEventArgs e)
{
    if (HistoryStack_Index > 1)
    {
        HistoryStack_Index--;
        fromHistory = true;
        webView.Navigate(HistoryStack[HistoryStack_Index-1]);
        updateNavButtons();
    }
}

private void forwardButton_Click(object sender, RoutedEventArgs e)
{
    if (HistoryStack_Index < HistoryStack.Count)
    {
        HistoryStack_Index++;
        fromHistory = true;
        webView.Navigate(HistoryStack[HistoryStack_Index-1]);
        UpdateNavButtons();
    }
}

private void UpdateNavButtons()
{
    this.backButton.IsEnabled = HistoryStack_Index > 1;
    this.forwardButton.IsEnabled = HistoryStack_Index < HistoryStack.Count;
}

private void WebView_Navigated(object sender, System.Windows.Navigation.NavigationEventArgs e)
{
    if (!fromHistory)
    {
        if (HistoryStack_Index < HistoryStack.Count)
        {
            HistoryStack.RemoveRange(HistoryStack_Index, HistoryStack.Count - HistoryStack_Index);
        }

        HistoryStack.Add(e.Uri);
        HistoryStack_Index++;
        UpdateNavButtons();
    }

    fromHistory = false;
}