Form

Form

org.apache.tapestry.form.Form

Non Visual Component

Description
A component that manages a HTML <form>. The other form-related components must be wrapped inside the Form.

When a form is submitted, it continues through the rewind cycle until after all of its wrapped elements have renderred. As the form component render (in the rewind cycle), they will be updating properties of the containing page and notifying thier listeners. Again: each form component is responsible not only for rendering HTML (to present the form), but for handling it's share of the form submission. Only after all that is done will the Form notify its listener.

See Also
Button, Checkbox, FieldLabel, Hidden, ImageSubmit, ListEdit, Option, PropertySelection, Radio, RadioGroup, Submit, TextArea, TextField, Upload, ValidField

Parameters

Name	Type	Direction	Required	Default	Description
listener	`IActionListener`	in	no		The listener, informed after the wrapped components of the form have had a chance to process their portion the request.
delegate	`IValidationDelegate`	in	no		Object used to assist in error tracking and reporting. A single instance is shared by all ValidField and FieldLabel comopnents within a single form.
stateful	boolean	in	no	true	If true (the default), then the component requires an active (i.e., non-new) HttpSession when triggered. Failing that, it throws a `StaleLinkException`. If false, then no check is necessary. Generally, forms are stateful, but it is possible to put a stateless form onto the Home page of an application.
direct	boolean	in	no	true	If true (the default), then the direct service is used for the form. This decreases the amount of work required to process the form submission, and is acceptible for most forms, even those that contain Foreaches (but not those that are inside a Foreach). An abbreviated form of the rewind cycle takes place, that only references the form and the components it wraps.
method	String	in	no	POST	The value to use for the method attribute of the <form> tag.

Body: rendered
Informal parameters: allowed
Reserved parameters: none

Examples

The Form component is used to provide a simple login page.

Username:

Password:

<form jwcid="@Form" listener="ognl:listeners.formSubmit">
 <table cellpadding="4">
   <tr><td>Username:</td><td><input jwcid="@TextField" value="ognl:visit.username" size="12"/></td>
  </tr>
   <tr><td>Password:</td><td><input jwcid="@TextField" value="ognl:visit.password" hidden="ognl:true" size="12"/></td>
  </tr>
  <tr align="right">
   <td colspan="2"><input type="submit" value="Login"/></td>
  </tr>
 </table>
</form>



public class LoginPage extends BasePage {

    public void formSubmit(IRequestCycle cycle) {
        Visit visit = (Visit) getVisit();
			
        if (visit.isAuthenticated()) {
            cycle.activate("Home");		
        } 
    }
}

public class Visit() implements Serializable  {
    private username;
    private password;

    public getUsername() { return username; }

    public setUsername(String value) { 
        username = value;
    }

    public getPassword() { return password; }

    public setPassword(String value) { 
        password = value;
    }

    public boolean isAuthenticated() {
        // Some authentication code.
        return true;
    }		
}