> 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/android/generate/pdf-thumbnails.md).

# Generate PDF page thumbnails in Android

Enhance PDF viewing experience with Apryse's library. Get a thumbnail preview of all pages in your PDF document using PDFViewCtrl. Learn how to request and cancel thumbnail images efficiently. The Apr

{% hint style="info" %}
Apryse's library provides a page thumbnail dialog which shows thumbnails of all PDF document pages. Fore more information, see [thumbnail browser ](/android/page-manipulation/thumbnails-view-a.md).
{% endhint %}

With [`PDFViewCtrl`](https://sdk.apryse.com/api/android/javadoc/reference/com/pdftron/pdf/PDFViewCtrl.html), you can get a thumbnail [`Bitmap`](https://developer.android.com/reference/android/graphics/Bitmap.html) image for each page in a PDF document.

The following example request thumbnail for page 3:

{% tabs %}
{% tab title="Java" %}
{% code lineNumbers="true" %}

```java
pdfViewCtrl.addThumbAsyncListener(new PDFViewCtrl.ThumbAsyncListener() {
    @Override
    public void onThumbReceived(int page, int[] buf, int width, int height) {
        try {
            Bitmap bitmap = Bitmap.createBitmap(width, height, Bitmap.Config.ARGB_8888);
            bitmap.setPixels(buf, 0, width, 0, 0, width, height);
            // use the bitmap 
        } catch (OutOfMemoryError oom) {
            // error
        }
  }
});

// request thumbnail for page 3
pdfViewCtrl.getThumbAsync(3);
```

{% endcode %}
{% endtab %}

{% tab title="Kotlin" %}
{% code lineNumbers="true" %}

```kotlin
pdfViewCtrl.addThumbAsyncListener(object:PDFViewCtrl.ThumbAsyncListener() {
    fun onThumbReceived(page:Int, buf:IntArray, width:Int, height:Int) {
        try {
            val bitmap = Bitmap.createBitmap(width, height, Bitmap.Config.ARGB_8888).apply { 
                this.setPixels(buf, 0, width, 0, 0, width, height)
            }
        } catch (oom:OutOfMemoryError) {
            // error
        }
    }
})

// request thumbnail for page 3
pdfViewCtrl.getThumbAsync(3)
```

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

where `pdfViewCtrl` is an instance of `PDFViewCtrl`.

{% hint style="info" %}
It is recommended you cancel all thumbnail requests once they are no longer needed. To cancel all thumbnail request, use `PDFViewCtrl.cancelAllThumbRequests()`.
{% endhint %}


---

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