title: flutter pageview.builder duplicating texts
body: <p>in my flutter book app I fetch a text from JSON object and display it in <code>PageView.builder</code>. and after it fetches and displays in first page and when it goes to the next page it duplicate the first page instead of displaying the remaining text file.</p>
  <pre><code>Container(
                height: height,
                width: width,
                child: PageView.builder(
                    itemBuilder: (context, index){
                      return RichText(
                        textDirection: TextDirection.rtl,
                        text: TextSpan(
                          text: '',
                          style: DefaultTextStyle.of(context).style,
                          children: &lt;TextSpan&gt;[
                            for (var i = 1; i &lt;= count; i++) ...{
                              TextSpan(
                                text: quran.getVerse(widget.id, i, verseEndSymbol: false),
                                style: TextStyle(
                                    fontSize: 26,
                                    fontWeight: FontWeight.bold,
                                    fontFamily: 'kitab'),
                              ),
                              TextSpan(
                                text: quran.getVerseEndSymbol(i),
                                style: TextStyle(
                                  color: Colors.cyanAccent,
                                  fontSize: 26,
                                  fontWeight: FontWeight.bold,
                                  fontFamily: 'kitab',
                                ),
                              ),
                            }
                          ],
                        ),
                      );
                    }),
              );
  </code></pre>
  <p>how can I split those text and display it in a pages?</p>