Md. Ashik Ali Khan: JSF2

Tuesday, November 15, 2016

Quick Solution: change selectOneMenu List based on inputText value

You need a <f:ajax listener> inside inputText. The inputChanged method will be called after value changed in inpuText field and update the list of selectOneMenu.

Here id of selectOneMenu is result. And that is mentioned in render attribute of <f:ajax listener>.

The JSF page: index.xhtml

<?xml version='1.0' encoding='UTF-8' ?>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml"
      xmlns:h="http://java.sun.com/jsf/html"
      xmlns:f="http://java.sun.com/jsf/core">
    <h:head>
        <title>Test</title>
    </h:head>
    <h:body>
        <h:form>
            <h:inputText value="#{valueTest.input}">

                <f:ajax listener="#{valueTest.inputChanged}" render="result"/>
            </h:inputText>

            <h:selectOneMenu id="result">
                <f:selectItems value="#{valueTest.lst}" />
            </h:selectOneMenu>
        </h:form>


    </h:body>
</html>

Managed Bean: ValueTest.java

@ManagedBean
@RequestScoped
public class ValueTest {

    /**
     * Creates a new instance of ValueTest
     */
    public ValueTest() {
    }

    @PostConstruct
    private void init()
    {
        lst = new ArrayList();
    }

    private String input;

    private List lst;

    private String result;
    public String getInput() {
        return input;
    }

    public void setInput(String input) {
        this.input = input;
    }

    public String getResult() {
        return result;
    }

    public void setResult(String result) {
        this.result = result;
    }


    public void inputChanged(AjaxBehaviorEvent e)
    {
        result = input;
        lst.clear();
        if(result.equals("01"))
        {
            lst.add("01");
            lst.add("02");
        }
        else if(result.equals("05"))
        {
            lst.add("05");
            lst.add("06");
        }
    }

    public List getLst() {
        return lst;
    }

    public void setLst(List lst) {
        this.lst = lst;
    }

}

Monday, June 20, 2016

Quick Solution: Download csv file in JSF 2

In xhtml file, I use primefaces command button. You can also use h:commandButton.

<h:form>

<p:commandButton value="Download File" action="#{branchDownload.download}"
ajax="false" />

</h:form>

In Managed Bean class, download() method is as follows:

@ManagedBean
@RequestScoped
public class BranchDownload {

// Your code

// download method

public void download()
    {
        String file_name = "FILE.csv" ;

        FacesContext fc = FacesContext.getCurrentInstance();
        ExternalContext ec= fc.getExternalContext();
        ec.responseReset();
        ec.setResponseContentType("text/csv");
        ec.setResponseHeader("Content-Disposition", "attachment; filename=\""+file_name + "\"");

        BufferedOutputStream csvOut;
        try {
            csvOut = new BufferedOutputStream(ec.getResponseOutputStream());
            BufferedWriter csvWriter = new BufferedWriter(new OutputStreamWriter(csvOut, "UTF-8"));

            csvWriter.append("1,2,3,4,5,6,7,8");
            csvWriter.append("\n");
            csvWriter.flush();

            csvWriter.append("One,2,Three,4,5,6,7,8");
            csvWriter.append("\n");
            csvWriter.flush();

            csvWriter.close();
            csvOut.close();
        } catch (IOException ex) {
            Logger.getLogger(BranchDownload.class.getName()).log(Level.SEVERE, null, ex);
        }
        finally{
            fc.responseComplete();
        }

    }

// End download method

}