| <document> |
| <body> |
| <section name="Examples"> |
| |
| |
| <p> |
| In this example, a Checkbox will be used alone to manipulate a property of the page. |
| </p> |
| |
| <subsection name="ViewAccounts.tml"> |
| |
| <source><![CDATA[ |
| <html xmlns:t="http://tapestry.apache.org/schema/tapestry_5_0_0.xsd"> |
| <body> |
| <h1>View Accounts</h1> |
| |
| <t:form> |
| <t:checkbox t:id="showall" onclick="this.form.submit();"/> <t:label for="showall"/> |
| </t:form> |
| |
| <t:grid t:id="accounts"/> |
| |
| </body> |
| </html> |
| ]]></source> |
| |
| <p> |
| The Grid component will do most of the work in terms of displaying the account data. |
| </p> |
| |
| <p> |
| Normally, we should bind the value parameter explicitly; here the component's id, "showAll", |
| matches against a property of the page and the value parameter is automatically bound |
| as a convienience. |
| </p> |
| |
| <p> |
| A small amount of JavaScript is provided in-line to submit the form when the checkbox is clicked. |
| </p> |
| |
| <p> |
| All Tapestry form control element components must be enclosed by a Form component. |
| </p> |
| |
| <p> |
| The Label component is responsible for rendering a <label> element connected to the checkbox. |
| This |
| is good for accessibility, it also provides a larger "target" to click on. |
| The label's text will be "Show All", derived from the property name. Using a Label component is |
| optional |
| but recommended. |
| </p> |
| |
| |
| </subsection> |
| |
| <subsection name="ViewAccounts.java"> |
| |
| <source><![CDATA[ |
| public class ViewAccount |
| { |
| @Persist |
| private boolean _showAll; |
| |
| @Inject |
| private AccountDAO _accountDAO; |
| |
| public boolean isShowAll() { return _showAll; } |
| |
| public void setShowAll(boolean showAll) { _showAll = showAll; } |
| |
| public List<Account> getAccounts() |
| { |
| return _showAll ? _accountDAO.getAllAccounts() : _accountDAO.getActiveAccounts(); |
| } |
| }]]></source> |
| |
| <p> |
| The component updates the _showAll field, and that's used to determine which |
| set of accounts should be provided to the Grid component. As always in Tapestry, you |
| must be careful to mark fields persistent if they need to hold their value between |
| the action request (the form submission) and the render request. |
| </p> |
| |
| |
| </subsection> |
| |
| |
| </section> |
| </body> |
| </document> |
