If I am creating a Jasper report template file in the iReports designer, is it possible to prevent a static text field from displaying if a field in its datasource is empty?
Is it possible to perhaps hide an element if a field value is NULL or empty?
Yes, it is possible.
1. Using "Print When Expression" property for static and text fields
Sample for hiding NULL or "empty" string value:
<staticText>
<reportElement x="52" y="16" width="100" height="20">
<printWhenExpression><![CDATA[$F{field1} != null && $F{field1}.trim().length()>0]]></printWhenExpression>
</reportElement>
<textElement/>
<text><![CDATA[Static text]]></text>
</staticText>
<textField>
<reportElement x="170" y="15" width="100" height="20">
<printWhenExpression><![CDATA[$F{field2} != null && $F{field2}.trim().length()>0]]></printWhenExpression>
</reportElement>
<textElement/>
<textFieldExpression><![CDATA[$F{field2}]]></textFieldExpression>
</textField>
2. Using "Blank When Null" property for text fields
Sample for hiding text field with NULL value:
<textField isBlankWhenNull="true">
<reportElement x="340" y="15" width="100" height="20"/>
<textElement/>
<textFieldExpression><![CDATA[$F{field3}]]></textFieldExpression>
</textField>
3. Using "No Data" band for empty datasource - no data returns
If datasource is empty you can use "No Data" band with static fields you needs. For using this band you must set "When No Data" report's property to "No Data Section".
Sample:
<?xml version="1.0" encoding="UTF-8"?>
<jasperReport .. whenNoDataType="NoDataSection" ..>
...
<noData>
<band height="50">
<staticText>
<reportElement x="236" y="18" width="100" height="20"/>
<textElement/>
<text><![CDATA[No data]]></text>
</staticText>
</band>
</noData>
</jasperReport>