Removing blank lines from report

[wcound]

I am using   Jaspersoft Studio    6.4.3.final to create a report.

In this report I have two string variables v_main at the report level and v_sub at the dataset level. 

   <variable name="v_main" class="java.lang.String" resetType="None">
        <initialValueExpression><![CDATA[null]]></initialValueExpression>
    </variable>

     <variable name="v_sub" class="java.lang.String" resetType="None">
            <variableExpression><![CDATA[$F{T_TEXT}]]></variableExpression>
            <initialValueExpression><![CDATA[null]]></initialValueExpression>
        </variable>

The string field T_TEXT from the dataset is used to set the v_sub value and is returned to v_main.

<returnValue fromVariable="v_sub" toVariable="v_main"/>

I then use the variable in a text field to display some text.

           <textField evaluationTime="Band" isBlankWhenNull="true">
                    <reportElement positionType="Float" mode="Opaque" x="0" y="0" width="320" height="10" isRemoveLineWhenBlank="true" backcolor="#B1FCFC" >
                        <property name="com.jaspersoft.studio.unit.height" value="pixel"/>
                    </reportElement>
                    <textElement>
                        <font fontName="Arial" size="8"/>
                    </textElement>
                    <textFieldExpression><![CDATA[LEN( $V{v_main})!=null?"Display This Text ":null]]></textFieldExpression>
                </textField>

The problem I am having is when the value in this field is null the field is still taking up space in the report.

I have added LEN( $V{v_main})!=null as a print when expression on this field to remove the blank line but have not been able to get it to work.

Any suggestions?

[dinu5]

I am not sure if this works. ($F{FieldName}==null)?" ":$F{FieldName} or Tick mark "Blank when NULL"' 

[JTU]

I can see that your field has positiontype="Float". Are all other fields that are below the Position type="Float" as well? If they are they should be moved upwards. If you have them set as Fix Relative to Top then they will be displayed where they are designed by your x&y position.

[wcound]

All of the fields below are set to Float.

This field that uses the expression is the only field in the report that does not move upwards.

[wcound]

This field is displayed in the page header band and in order to display the field I have to set the evaluation time to Band.

When I change the evaluation time to something else the field does move up when blank, however I no longer get any data displaying in the field.

I will test out moving the field from the  header band to the detail band to see if that makes any difference.

I have tested out moving the field to the detail band but that does not make any difference.