setting datasource of subreport and NeedDataSource event problem

[Lior ef]

hi guys,

i have a master detail report that uses a certain table from a DataSet as DataSource,

i've set:

MasterReport.DataSource = DataSet1.Table1 and 

MasterReport.DataMember = "GetEnumerator".

until now, it works fine.

now, i have a subreport in the MasterReport and i want to set its' datasource,

because DataSet1 hold 2 tables, and Table1 is the DataSource of the MasterReport,

i want to take the same DataSet1 and get Table2 from it to put as DataSource of the subreport,

something like that:

((MasterReport.DataSource as DataSet1.Table1).DataSet.Tables["Table2"]

of course this doesn't work because MasterReport.DataSourc is ObjectDataSource type.

how can i do want i need in a better way?

i want the same instance of the Dataset to be the datasource of the two reports but the datamember will be two different tables.

i've attached a screenshot of the way my MasterReport is built.

second problem i have is that i catched in MasterReport this event subReport1_NeedDataSource

(definition of subReport1: "private SubReport subReport1;") and this event MasterReport_NeedDataSource,

i've put a breakpoint in them and it never triggers. any suggestions why that happens?

thanks in advance.

lior.

[Patrick]

Regarding your 2nd problem... if the subreport, or the master report for that matter, has a data source already bound to it, the corresponding NeedDataSource() event will not fire. At least that's been my experience.

What I've been doing is releasing the .DataSource property at runtime when the GUI creates an instance of the report. Here's some code... hope it helps.

    public BudgetComparativeMasterReport(string fy_code, string fy_period, string rollup_section_ind, string dept_code, string comparative_report_type)
    {
      /// <summary>
      /// Required for Telerik Reporting designer support
      /// </summary>
      InitializeComponent();

      //
      // TODO: Add any constructor code after InitializeComponent call
      //

      try
      {
        // place the values passed as arguments in the report parameters
        this.ReportParameters["fy_code"].Value = fy_code;
        this.ReportParameters["fy_period"].Value = fy_period;
        this.ReportParameters["rollup_section_ind"].Value = rollup_section_ind;
        this.ReportParameters["dept_code"].Value = dept_code;
        this.ReportParameters["fiscal_period_ending"].Value = ReportUtilities.GetPeriodEndingDate(fy_code, fy_period);
        this.ReportParameters["comparativeReportType"].Value = comparative_report_type;

        // execution of the following line will force the BudgetComparativeMasterReport_NeedDataSource event to be raised
        this.DataSource = null;

        // when the .DataSource property is set to null, we need to wire-up the NeedDataSource event handler
        // however, the event will *not* be raised if the report already has a data source bound to it
        this.NeedDataSource += new EventHandler(BudgetComparativeMasterReport_NeedDataSource);
      }
      catch (System.Exception ex)
      {
        // An error has occurred while filling the data set. Please check the exception for more information.
        System.Diagnostics.Debug.WriteLine(ex.Message);
      }

    }

    /// <summary>
    /// This event is fired at the start of report processing, but only if the report has no data source bound to it!
    /// </summary>
    /// <param name="sender"></param>
    /// <param name="e"></param>
    private void BudgetComparativeMasterReport_NeedDataSource(object sender, EventArgs e)
    {
      try
      {
        if (this.dataSet == null)
        {
          // collect the report parameter values assigned in the class constructor, the values
          // will be substituted in the SQL statement
          string fyCode = (sender as Telerik.Reporting.Processing.Report).Parameters["fy_code"].ToString();
          string rollupSectionInd = (sender as Telerik.Reporting.Processing.Report).Parameters["rollup_section_ind"].ToString().ToUpper();
          string deptCode = (sender as Telerik.Reporting.Processing.Report).Parameters["dept_code"].ToString();

          string connectionString = ETLReportsLibrary.Properties.Settings.Default.oracleConnectionString.ToString();
          string sqlSelect =
            @"SELECT
                DISTINCT dept_code,
                dept_name,
                fy_code,
                rollup_section_ind
              FROM
                budget_comparative_report_view
              WHERE
                fy_code = '{0}' AND
                Upper(rollup_section_ind) = '{1}' AND
                dept_code LIKE '{2}'";

          OracleDataAdapter da = new OracleDataAdapter(string.Format(sqlSelect, fyCode, rollupSectionInd, deptCode), connectionString);
          this.dataSet = new DataSet();
          da.Fill(this.dataSet);
        }
        (sender as Telerik.Reporting.Processing.Report).DataSource = this.dataSet;
      }
      catch (Exception ex)
      {
        System.Diagnostics.Debug.WriteLine(ex.Message);
      }

    }

[Lior ef]

hi Patrick,

thanks a lot, it works, the event is triggered.

now i'll wait for my first question to be answered :)

[Peter]

Hello Lior ef,

In order to use the Dataset's Table2 to set the SubReport's DataSource you have to create a new ObjectDataSource component with DataMember: Table2.

For code snippets check out the How to: Bind to a DataSet help article.

Kind regards,
Peter
the Telerik team

[Lior ef]

peter, thanks for the guidance, i found the answer, i'm writing it here for other people to use:

problem: setting the datasource of a subreport at runtime, from inside the master report using NeedData event, master reports' datasource holds a dataset we want to use.

answer:
first make sure to put this code at the c'tor of the master report so the event will trigger

subReport1.ReportSource.DataSource = null;
subReport1.NeedDataSource += new EventHandler(subReport1_NeedDataSource);

second:

private void subReport1_NeedDataSource(object sender, EventArgs e)
{
    var objectDataSource = new ObjectDataSource();
    objectDataSource.DataSource = this.DataSource; // this => Master Report
    objectDataSource.DataMember = "TableName";

    subReport1.ReportSource.DataSource = objectDataSource;
}

[Bhushan]

Hi Lior ef ,

Can you plz tell me where put the following code ,what is  c'tor of the master report .not understand that.

subReport1.ReportSource.DataSource = null;

subReport1.NeedDataSource += new EventHandler(subReport1_NeedDataSource);

thanks in advance.
Bhushan.






[Massimiliano Bassili]

c'tor = constructor, referring to the report constructor.

[Rob]

This is a very old thread, but it's exactly what I need to achieve.

My reports run within a MVC web application that is deployed to customers sites.

The customer has a setup web page which allows them to set select the database and servers to report off, which means I don't want to save connection strings in config files.

I have everything working ( passing the connection string to the report from the View) , however I am struggling to pass the connection string to the sub reports

This solution looked perfect, except it seems that the versions have changed now ,

 'subReport1.ReportSource.DataSource' no longer exists.

Can anyone suggest a way to either access the sub reports Datasource from the master report or visa versa? ( read the masters from the sub report)

Thanks!

Rob

[Rob]

I found a way to do this..

My solution is to pass report parameters from the master to the subreport and pass the connectionstring as a report parameter ( string)

Remove the Datasource from the subreport so you get the 'needsDatasource' event

Private Sub AuditDetails_NeedDataSource(sender As Object, e As EventArgs) Handles Me.NeedDataSource
    SqlDataSource1.ConnectionString = Me.ReportParameters("ConnString").Value
    Me.DataSource = SqlDataSource1
End Sub

And update your data source with the connectionsting passed from the master report.

Hop this helps someone..

Rob

[Mahmoud]

Anyone can help me achieve this:

I have a report that is grouped by ID, in the footer of each group I need to have a TABLE that loads data from the database based on the ID of the spoken group. In the TABLE DataSource, I need to know how I can read the ID of the group. 

Thank you very very much for you help.

-m

[KS]

Hi,

Filter the table's data with the ReportItem.DataObject - http://www.telerik.com/help/reporting/data-items-how-to-use-data-object.html

-KS