> For the complete documentation index, see [llms.txt](https://docs.apryse.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.apryse.com/xamarin/guides/viewer-components/page-label-editor-a.md).

# Page label editor: add or modify PDF pages in Xamarin

Learn how to use PageLabelDialogFragment in Xamarin.Android to manage page labels in PDF documents. Follow this tutorial for step-by-step instructions. The Apryse Xamarin SDK streamlines secure, serve

{% hint style="info" %}
**This tutorial only applies to Xamarin.Android.**
{% endhint %}

The [`PageLabelDialogFragment`](https://sdk.apryse.com/api/xamarinandroid/tools/api/pdftron.PDF.Dialog.PageLabel.PageLabelDialog.html) allows you to add or modify the page labels in a PDF document. Page labels are typically used to describe a page, such as allowing for non-sequential page numbering (such as the inclusion of Roman numerals at the beginning of a book) or the addition of arbitrary labels.

![](https://653871032-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FgjsBtuYmcKhWOdM9VCg4%2Fuploads%2Fgit-blob-d4dc4d011e93991121aa9fad2e9c2a2c5cd221dc%2F45fbb90d9b77a3ff893cb92f02c01975e1d2d51e-600x1200.gif?alt=media)

## Show the page label editor

The page label editor can be shown from an activity by calling the following method:

{% tabs %}
{% tab title="C#" %}
{% code lineNumbers="true" %}

```csharp
public void ShowPageLabelSettingsDialog(FragmentManager fragmentManager, int fromPage, int toPage, int pageCount)
{
    var dialog = pdftron.PDF.Dialog.PageLabel.PageLabelDialog.NewInstance(fromPage, toPage, pageCount);
    dialog.SetStyle((int)DialogFragmentStyle.NoTitle, Resource.Style.PDFTronAppTheme);
    dialog.Show(fragmentManager, "page_label_dialog");
}
```

{% endcode %}
{% endtab %}
{% endtabs %}

In order to recieve the inputs from the page label editor, you will also need to subscribe to completion events from the page label dialog:

{% tabs %}
{% tab title="C#" %}
{% code lineNumbers="true" %}

```csharp
public class MyActivity : AppCompatActivity, Android.Arch.Lifecycle.IObserver
{
    public void PageLabelObserveOnComplete(AppCompatActivity activity, PDFViewCtrl pdfViewCtrl)
    {
        var viewModel = ViewModelProviders.Of(activity).Get(Java.Lang.Class.FromType(typeof(pdftron.PDF.Dialog.PageLabel.PageLabelSettingViewModel))) as pdftron.PDF.Dialog.PageLabel.PageLabelSettingViewModel;
        viewModel.ObserveOnComplete(activity, this);
    }

    public void OnChanged(Java.Lang.Object p0)
    {
        if (p0 is pdftron.PDF.Tools.Utils.Event)
        {
            var someEvent = p0 as pdftron.PDF.Tools.Utils.Event;
            if (!someEvent.HasBeenHandled)
            {
                var actualEvent = someEvent.ContentIfNotHandled;
                if (actualEvent is pdftron.PDF.Dialog.PageLabel.PageLabelSetting)
                {
                    var pageLabelSettingEvent = actualEvent as pdftron.PDF.Dialog.PageLabel.PageLabelSetting;
                    pdftron.PDF.Dialog.PageLabel.PageLabelUtils.SetPageLabel(mPdfViewCtrl, pageLabelSettingEvent);
                }
            }
        }
    }
}
```

{% endcode %}
{% endtab %}
{% endtabs %}


---

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