How to create dynamic report through JRXML???

[Sundhas]

Hey! I am working on jrxml to create dynamic re0ports. I have parameterized the columns i.e. the jrxml for that report can be used to generate other reports as well.

However, i have not managed to make the fields flexible. That is, if the user selects 4 columns it would work but if 1 or 2 or 3 columns are selected, it gives an error since the field names are unidentified.

Please post a solution urgently if something like a default expression for fieldname can be created or a for loop/java script can be used.

Moreover, how can jasper designer be exactly used to achieve this?

The jrxml is as follows:

<?xml version="1.0"?>
<!DOCTYPE jasperReport
  PUBLIC "-//JasperReports//DTD Report Design//EN"
  "http://jasperreports.sourceforge.net/dtds/jasperreport.dtd">
 
<jasperReport name="report1">
 
    <parameter name="reportTitle" class="java.lang.String"/>
    <parameter name="author" class="java.lang.String"/>
    <parameter name="startDate" class="java.lang.String"/>
 
 <parameter name="C1" class="java.lang.String">
        <defaultValueExpression>
            new java.lang.String("")
        </defaultValueExpression>
    </parameter>
 
    <parameter name="C2" class="java.lang.String">
        <defaultValueExpression>
            new java.lang.String("")
        </defaultValueExpression>
    </parameter>
 
    <parameter name="C3" class="java.lang.String">
        <defaultValueExpression>
            new java.lang.String("")
        </defaultValueExpression>
    </parameter>
 
    <parameter name="C4" class="java.lang.String">
        <defaultValueExpression>
            new java.lang.String("default parameter value")
        </defaultValueExpression>
    </parameter>
 
    <field name="COLUMN_1" class="java.lang.Integer"/>
    <field name="COLUMN_2" class="java.lang.Integer"/>
    <field name="COLUMN_3" class="java.lang.Integer"/>
    <field name="COLUMN_4" class="java.lang.Integer"/>
 
    <title>
        <band height="60">
            <textField>
                <reportElement x="0" y="10" width="500" height="40"/>
                <textElement textAlignment="Center">
                    <font size="24"/>
                </textElement>
                <textFieldExpression class="java.lang.String">
                    <![CDATA[$P{reportTitle}]]>
                </textFieldExpression>
            </textField>
            <textField>
                <reportElement x="0" y="40" width="500" height="20"/>
                <textElement textAlignment="Center"/>
                <textFieldExpression class="java.lang.String">
                    <![CDATA["Run by: " + $P{author}
                        + " on " + $P{startDate}]]>
                </textFieldExpression>
            </textField>
        </band>
    </title>
 
 
<columnHeader>
        <band height="30">
            <rectangle>
                <reportElement x="0" y="0" width="500" height="25"/>
                <graphicElement/>
            </rectangle>
 
            <textField>
                <reportElement x="0" y="5" width="170" height="15"/>
                <textFieldExpression class="java.lang.String">
                    <![CDATA[$P{C1}]]>
                </textFieldExpression>
            </textField>
 
            <textField>
                <reportElement x="70" y="5" width="170" height="15"/>
              <textFieldExpression class="java.lang.String">
                    <![CDATA[$P{C2}]]>
                </textFieldExpression>
            </textField>
 
            <textField>
                <reportElement x="150" y="5" width="150" height="15"/>
              <textFieldExpression class="java.lang.String">
                    <![CDATA[$P{C3}]]>
                </textFieldExpression>
            </textField>
 
            <textField>
                <reportElement x="300" y="5" width="150" height="15"/>
              <textFieldExpression class="java.lang.String">
                    <![CDATA[$P{C4}]]>
                </textFieldExpression>
 
            </textField>
 
 
            </band>
    </columnHeader>
 
 
<detail>
        <band height="20">
 
            <textField>
                <reportElement x="5" y="0" width="50" height="15"/>
                <textElement/>
                <textFieldExpression class="java.lang.Integer">
                    <![CDATA[$F{COLUMN_1}]]>
                </textFieldExpression>
            </textField>
 
            <textField>
                <reportElement x="90" y="0" width="150" height="15"/>
                <textElement/>
                <textFieldExpression class="java.lang.Integer">
                    <![CDATA[$F{COLUMN_2}]]>
                </textFieldExpression>
            </textField>
 
            <textField>
                <reportElement x="170" y="0" width="50" height="15"/>
                <textElement/>
                <textFieldExpression class="java.lang.Integer">
                    <![CDATA[$F{COLUMN_3}]]>
                </textFieldExpression>
            </textField>
 
            <textField>
                <reportElement x="320" y="0" width="150" height="15"/>
                <textElement/>
                <textFieldExpression class="java.lang.Integer">
                    <![CDATA[$F{COLUMN_4}]]>
                </textFieldExpression>
            </textField>
 
        </band>
    </detail>
 
</jasperReport> 

[Ricardo Mariaca]

I recommend to use DynamicReports, is open source and you can create dynamic reports very easy