Why does the detail-band grow on second page? - jasper-reports

Question

I'm defining a report for invoices, an invoice may have n items (rows) in the detail. I defined a dataset in order to display the items without the need of a subreport. Here my Detail-band:
<detail>
<band height="275" splitType="Stretch">
<rectangle>
<reportElement x="0" y="0" width="60" height="16" uuid="590f4cac-fba0-4e0b-aa74-db059a817946"/>
</rectangle>
<rectangle>
<reportElement x="60" y="0" width="140" height="16" uuid="1cc31301-e884-4648-952d-a68bcaa12b23"/>
</rectangle>
<rectangle>
<reportElement x="200" y="0" width="31" height="16" uuid="ac690ad3-a913-454f-80d0-574505609db1"/>
</rectangle>
<rectangle>
<reportElement x="231" y="0" width="100" height="16" uuid="6d623fd0-df6f-4ffd-b92b-8f18e0d2d5b2"/>
</rectangle>
<rectangle>
<reportElement x="331" y="0" width="37" height="16" uuid="afef801a-3280-4810-8d85-c1f591d2b75b"/>
</rectangle>
<staticText>
<reportElement x="3" y="2" width="44" height="11" uuid="f525bb2b-106a-44a3-9fb0-817f1eeb8260"/>
<textElement>
<font size="6"/>
</textElement>
<text><![CDATA[Artikel]]></text>
</staticText>
<staticText>
<reportElement x="63" y="2" width="126" height="11" uuid="0f97aa9e-cb83-4a95-92fc-fdc01e1506f1"/>
<textElement>
<font size="6"/>
</textElement>
<text><![CDATA[Beschreibung]]></text>
</staticText>
<staticText>
<reportElement x="207" y="2" width="22" height="11" uuid="6234d14c-abe2-482e-b6bb-f1c65dc19005"/>
<textElement textAlignment="Right">
<font size="6"/>
</textElement>
<text><![CDATA[Menge]]></text>
</staticText>
<staticText>
<reportElement x="237" y="2" width="92" height="11" uuid="2bd9712e-b8be-4b90-823d-a530f6c7dcba"/>
<textElement textAlignment="Right">
<font size="6"/>
</textElement>
<text><![CDATA[Einheitspreis]]></text>
</staticText>
<staticText>
<reportElement x="340" y="2" width="25" height="11" uuid="dbf02042-62f2-4b70-9b8b-fae588cb8055"/>
<textElement textAlignment="Right">
<font size="6"/>
</textElement>
<text><![CDATA[Rabatt]]></text>
</staticText>
<rectangle>
<reportElement x="368" y="0" width="70" height="16" uuid="54f1f443-d742-4287-8ae6-d06b04682bf4"/>
</rectangle>
<rectangle>
<reportElement x="437" y="0" width="34" height="16" uuid="f23aa7d5-3eb9-478a-a799-a8acfe96d7af"/>
</rectangle>
<rectangle>
<reportElement x="471" y="0" width="84" height="16" uuid="7b4a3a55-b161-44c7-8512-33a127d68ba3"/>
</rectangle>
<staticText>
<reportElement x="381" y="2" width="54" height="11" uuid="e12d9869-3dcd-4b81-89f8-b3a3c6b2e28c"/>
<textElement textAlignment="Right">
<font size="6"/>
</textElement>
<text><![CDATA[MwSt. Grundlage]]></text>
</staticText>
<staticText>
<reportElement x="441" y="2" width="28" height="11" uuid="fb7f8a0e-1632-454f-9742-5179831c8dc4"/>
<textElement textAlignment="Right">
<font size="6"/>
</textElement>
<text><![CDATA[MwSt.]]></text>
</staticText>
<staticText>
<reportElement x="505" y="2" width="47" height="11" uuid="da9a079f-dc7e-4fef-9f31-eabd65340967"/>
<textElement textAlignment="Right">
<font size="6"/>
</textElement>
<text><![CDATA[MwSt. Betrag]]></text>
</staticText>
<rectangle>
<reportElement x="0" y="16" width="60" height="248" uuid="cd7f5e9a-aeae-425c-8783-22084707b432"/>
</rectangle>
<rectangle>
<reportElement x="60" y="16" width="140" height="248" uuid="01ee9155-aed8-4a55-8160-5f73ac6b1085"/>
</rectangle>
<rectangle>
<reportElement x="200" y="16" width="31" height="248" uuid="66698906-69ee-4fdc-8a04-ce14372bd065"/>
</rectangle>
<rectangle>
<reportElement x="231" y="16" width="100" height="248" uuid="0c260fbe-b300-4962-ad7b-ff7666fa2baa"/>
</rectangle>
<rectangle>
<reportElement x="331" y="16" width="37" height="248" uuid="1902828b-f84c-440c-8e3f-24cdffea33ec"/>
</rectangle>
<rectangle>
<reportElement x="368" y="16" width="69" height="248" uuid="880c1b82-4316-493a-b5b3-c4342bbb74c9"/>
</rectangle>
<rectangle>
<reportElement x="437" y="16" width="34" height="248" uuid="ee1c4e69-b69e-4cc8-9b83-24e9867012de"/>
</rectangle>
<rectangle>
<reportElement x="471" y="16" width="84" height="248" uuid="eade602d-0afa-4a6e-a3aa-5de350dc2ee5"/>
</rectangle>
<componentElement>
<reportElement x="0" y="16" width="555" height="17" uuid="be7e1e99-0990-4f3d-beaf-b304c08be036"/>
<jr:list xmlns:jr="http://jasperreports.sourceforge.net/jasperreports/components" xsi:schemaLocation="http://jasperreports.sourceforge.net/jasperreports/components http://jasperreports.sourceforge.net/xsd/components.xsd" printOrder="Vertical">
<datasetRun subDataset="items" uuid="ab906203-20bb-4347-806b-ef000f212bf9">
<dataSourceExpression><![CDATA[new net.sf.jasperreports.engine.data.JRBeanCollectionDataSource($F{righeDocumento})]]></dataSourceExpression>
</datasetRun>
<jr:listContents height="17" width="555">
<textField>
<reportElement x="3" y="2" width="56" height="14" uuid="448ef958-9459-4ab1-8896-f5b65dd7a552"/>
<textFieldExpression><![CDATA[$F{articolo}]]></textFieldExpression>
</textField>
<textField>
<reportElement x="63" y="2" width="136" height="14" uuid="24634427-d38f-4679-8996-a96d5051774b"/>
<textFieldExpression><![CDATA[$F{descrizione}]]></textFieldExpression>
</textField>
<textField>
<reportElement x="236" y="2" width="92" height="14" uuid="20bda0b8-a3c0-47e7-bdff-555c481a894d"/>
<textElement textAlignment="Right"/>
<textFieldExpression><![CDATA[new DecimalFormat("0.00 €").format($F{prezzo})]]></textFieldExpression>
</textField>
<textField>
<reportElement x="207" y="2" width="21" height="14" uuid="61766ba4-57d0-4509-ac41-ffd7bb4e12ef"/>
<textElement textAlignment="Right"/>
<textFieldExpression><![CDATA[$F{quantita}]]></textFieldExpression>
</textField>
<textField>
<reportElement x="338" y="2" width="27" height="14" uuid="535705c6-d0b6-401d-b767-efafb3ba42f7"/>
<textElement textAlignment="Right"/>
<textFieldExpression><![CDATA[$F{sconto} == null ? "" : $F{sconto}+" %"]]></textFieldExpression>
</textField>
<textField>
<reportElement x="439" y="2" width="28" height="14" uuid="0dc5fa14-efac-4c5b-898a-9a9152e588f7"/>
<textElement textAlignment="Right"/>
<textFieldExpression><![CDATA[$F{aliquota}]]></textFieldExpression>
</textField>
<textField>
<reportElement x="375" y="2" width="59" height="14" uuid="2772b49b-5355-463d-bebf-856537a416a3"/>
<textElement textAlignment="Right"/>
<textFieldExpression><![CDATA[new DecimalFormat("0.00 €").format($F{costo})]]></textFieldExpression>
</textField>
<textField>
<reportElement x="482" y="2" width="70" height="14" uuid="0259a153-a0c2-4589-b296-fdca4ceeed2b"/>
<textElement textAlignment="Right"/>
<textFieldExpression><![CDATA[new DecimalFormat("0.00 €").format($F{iva})]]></textFieldExpression>
</textField>
</jr:listContents>
</jr:list>
</componentElement>
</band>
</detail>
The result is to see in the following pictures:
Example with many rows:
Example with two rows:
The problem is that when I have more rows it includes a second page (not shown here in my question) with header and footer, the detail is empty. The rest as we can see from the pics is OK.
Why? How do I fix it?

Answer 1

You have chosen a strange way to create this report, the normal way would be to make the detail band represent 1 article line in your invoice (hence detail band would have the height of 14)
Then if you need to draw lines to the bottom of the page you can always use the background band.
What is happening now?, probably the list overflows in your detail band that also have empty space under it, it can not create another one on same page and move the space to next page.
Solution Use the normal way of jasper report, datasource containing your lines, header in columnHeader band, fields in detail band (height 14) and your vertical lines in
the background band, also exports as to excel etc will be much cleaner.
If you like to keep your list, move all the rectangles to the
background band and reduce height of detail band to remaining
components (header + list height)