org.apache.click.extras.control
Class LinkDecorator

java.lang.Object
  org.apache.click.extras.control.LinkDecorator

All Implemented Interfaces:

Serializable, Decorator

public class LinkDecorator
extends Object
implements Decorator, Serializable

Provides a table column AbstractLink and ActionButton Decorator.

LinkDecorator Example

The example below uses a LinkDecorator to render the row ActionLinks in the tables "Action" column.

 public class EditTable extends BorderPage {

     public Table table = new Table();
     public ActionLink editLink = new ActionLink("edit", "Edit", this, "onEditClick");
     public ActionLink deleteLink = new ActionLink("delete", "Delete", this, "onDeleteClick");

     public EditTable() {
         table.addColumn(new Column("name"));
         table.addColumn(new Column("email"));
         table.addColumn(new Column("holdings"));
         table.addColumn(new Column("dateJoined"));

         Column column = new Column("Action");
         ActionLink[] links = new ActionLink[]{editLink, deleteLink};
         column.setDecorator(new LinkDecorator(table, links, "id"));
         table.addColumn(column);

         deleteLink.setAttribute("onclick", "return window.confirm('Please confirm delete');");
     }

     public boolean onEditClick() {
         Integer id = editLink.getValueInteger();
         Customer customer = getCustomerService().getCustomer(id);

         ..
     }

     public boolean onDeleteClick() {
         Integer id = deleteLink.getValueInteger();
         getCustomerService().deleteCustomer(id);
         return true;
     }

     public void onRender() {
         List customers = getCustomerService().getCustomersSortedByName(12);
         table.setRowList(customers);
     }
 } 

The LinkDecorator class automatically supports table paging.

Multiple parameters

On rare occasions it is useful to add extra parameters or even replace the default parameter.

In such cases you can override the methods renderActionLink or renderActionButton.

In the example below we want to send both the state and postCode parameters to the AddressPage:

 public class SelectPostCode extends BorderPage {

     private Table table = new Table("table");

     public SelectPostCode() {
         ...
         PageLink selectPostCode = new PageLink("select", AddressPage.class);
         Column action = new Column("action");
         String idProperty = "postCode";
         LinkDecorator decorator = new LinkDecorator(table, selectPostCode, idProperty) {
             protected void renderActionLink(HtmlStringBuffer buffer, AbstractLink link, Context context, Object row, Object value) {
                 // We want to add the PostCode "state" as an extra parameter
                 // to the action link
                 link.setParameter("state", ((PostCode) row).getState());

                 // You can manipulate the link parameters as needed, and
                 // even remove the default idProperty parameter.
                 // Object currentValue = link.getParameters().remove(this.idProperty);

                 // NB we invoke the super implementation here for default rendering to continue
                 super.renderActionLink(buffer, link, context, row, value);
             }
         }
         action.setDecorator(decorator);
         table.addColumn(action);
     };

     public void onRender() {
         table.setRowList(getPostCodeService().getPostCodes());
     }
 } 

In the above example the LinkDecorator will extract the idProperty value ("state") for each object in the table. The PageLinks will render as follows:

 <a href="/mycorp/address-page.htm?postCode=6089&state=NSW>Select</a>
 

This class was inspired by Richardo Lecheta's ViewDecorator design pattern.

See Also:

ActionLink, PageLink, Serialized Form

Field Summary

protected ActionButton[]	buttonsArray The array of ActionButtons to render.
protected String	idProperty The row object identifier property.
protected AbstractLink[]	linksArray The array of AbstractLinks to render.
protected String	linkSeparator The link separator string, default value is " | ".
protected Map<?,?>	methodCache The method cached for rendering column values.
protected String	parameterName An optional parameter name for the idProperty.
protected Table	table The table to render the links for.

Constructor Summary

LinkDecorator(Table table, AbstractLink[] links, String idProperty)
Create a new AbstractLink table column Decorator with the given AbstractLinks array and row object identifier property name.

LinkDecorator(Table table, AbstractLink[] links, String idProperty, String parameterName)
Create a new AbstractLink table column Decorator with the given AbstractLinks array, row object identifier property name and parameter name.

LinkDecorator(Table table, AbstractLink link, String idProperty)
Create a new AbstractLink table column Decorator with the given actionLink and row object identifier property name.

LinkDecorator(Table table, ActionButton[] buttons, String idProperty)
Create a new ActionButton table column Decorator with the given ActionButtons array and row object identifier property name.

LinkDecorator(Table table, ActionButton[] buttons, String idProperty, String parameterName)
Create a new ActionButton table column Decorator with the given ActionButton array, row object identifier property name and parameter name.

LinkDecorator(Table table, ActionButton button, String idProperty)
Create a new AbstractLink table column Decorator with the given ActionButton and row object identifier property name.

LinkDecorator(Table table, List<? extends AbstractControl> controls, String idProperty)
Create a new table column Decorator with the given list of AbstractLinks or ActionButtons and row object identifier property name.

Method Summary

String	getLinkSeparator() Return the link separator string.
protected void	initButton(ActionButton button, Context context, Object value) Initialize the button value and parameters.
protected void	initLink(AbstractLink link, Context context, Object value) Initialize the link value and parameters.
String	render(Object row, Context context) Render the given row object using the links or buttons.
protected void	renderActionButton(HtmlStringBuffer buffer, ActionButton button, Context context, Object row, Object value) Render the button to the specified buffer.
String	renderActionButtons(Object row, Context context) Render the given row object using the actionButtons array.
protected void	renderActionLink(HtmlStringBuffer buffer, AbstractLink link, Context context, Object row, Object value) Render the link to the specified buffer.
String	renderActionLinks(Object row, Context context) Render the given row object using the actionLinks array.
void	setLinkSeparator(String value) Set the link separator string with the given value.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

idProperty

protected String idProperty

The row object identifier property.

linksArray

protected AbstractLink[] linksArray

The array of AbstractLinks to render.

buttonsArray

protected ActionButton[] buttonsArray

The array of ActionButtons to render.

linkSeparator

protected String linkSeparator

The link separator string, default value is " | ".

table

protected Table table

The table to render the links for.

methodCache

protected transient Map<?,?> methodCache

The method cached for rendering column values.

parameterName

protected String parameterName

An optional parameter name for the idProperty.

Constructor Detail

LinkDecorator

public LinkDecorator(Table table,
                     AbstractLink link,
                     String idProperty)

Create a new AbstractLink table column Decorator with the given actionLink and row object identifier property name.

Example usage of this constructor:

 Table table = new Table("table");

 public void onInit() {
     ... // setup other columns
     ActionLink selectState = new ActionLink("select");
     Column action = new Column("action");
     String idProperty = "state";
     LinkDecorator decorator = new LinkDecorator(table, selectState, idProperty);
     action.setDecorator(decorator);
     table.addColumn(action);
     ...
 }

 public void onRender() {
     // Populate the table rows with post code instances
     table.setRowList(getPostCodeService().getPostCodes());
 } 

In the above example the LinkDecorator will extract the idProperty value ("state") from each PostCode instance in the table.

The idProperty value will also be used as the name of the request parameter. In this example the idProperty value is "state" thus the request parameter name will also be "state".

For the PostCode "NSW" the PageLink will render as follows:

 <a href="/mycorp/postcodes.htm?state=NSW>Select</a> 

Parameters:

table - the table to render the links for

link - the AbstractLink to render

idProperty - the row object identifier property name

LinkDecorator

public LinkDecorator(Table table,
                     AbstractLink[] links,
                     String idProperty)

Create a new AbstractLink table column Decorator with the given AbstractLinks array and row object identifier property name.

Parameters:

table - the table to render the links for

links - the array of AbstractLinks to render

idProperty - the row object identifier property name

See Also:

LinkDecorator(org.apache.click.control.Table, org.apache.click.control.AbstractLink, java.lang.String)

LinkDecorator

public LinkDecorator(Table table,
                     AbstractLink[] links,
                     String idProperty,
                     String parameterName)

Create a new AbstractLink table column Decorator with the given AbstractLinks array, row object identifier property name and parameter name.

When the link is rendered, the parameter name is set as the row object identifier parameter. For example:

   // PageLink links to a Page where customers can be edited -> EditCustomerPage
   PageLink editLink = new PageLink("edit", EditCustomerPage.class);
   AbstractLink[] actions = new AbstractLink[] {editLink};
   Column column = new Column("id");
   table.addColumn(column);
   column.setDecorator(new LinkDecorator(table, actions, "id", "idParam")); 

If the table displayed a list of customers, the customer with id, "123", will render the following editLink:

 <a href="/mycorp/edit-customer.htm?idParam=123">edit</a> 

If the parameter name was not specified the row object identifier parameter will default to the given idProperty, in this case "id":

 <a href="/mycorp/edit-customer.htm?id=123">edit</a> 

Parameters:

table - the table to render the links for

links - the array of AbstractLinks to render

idProperty - the row object identifier property name

parameterName - a parameter name for the row object identifier

See Also:

LinkDecorator(org.apache.click.control.Table, org.apache.click.control.AbstractLink, java.lang.String)

LinkDecorator

public LinkDecorator(Table table,
                     ActionButton button,
                     String idProperty)

Create a new AbstractLink table column Decorator with the given ActionButton and row object identifier property name. The default linkSeparator for buttons is " ".

Parameters:

table - the table to render the links for

button - the ActionButton to render

idProperty - the row object identifier property name

See Also:

LinkDecorator(org.apache.click.control.Table, org.apache.click.control.AbstractLink, java.lang.String)

LinkDecorator

public LinkDecorator(Table table,
                     ActionButton[] buttons,
                     String idProperty,
                     String parameterName)

Create a new ActionButton table column Decorator with the given ActionButton array, row object identifier property name and parameter name.

When the button is rendered, the parameter name is set as the row object identifier parameter. For example:

   // PageButton links to a Page where customers can be edited -> EditCustomerPage
   PageButton editButton = new PageButton("edit", EditCustomerPage.class);
   ActionButton[] actions = new ActionButton[] {editButton};
   Column column = new Column("id");
   table.addColumn(column);
   column.setDecorator(new LinkDecorator(table, actions, "id", "idParam")); 

If the table displayed a list of customers, the customer with id, "123", will render the following editButton:

 <input onclick="javascript:document.location.href='/mycorp/edit-customer.htm?actionButton=edit&value=123&idParam=123';"/> 

If the parameter name was not specified the row object identifier parameter will default to "value":

 <input onclick="javascript:document.location.href='/mycorp/edit-customer.htm?actionButton=edit&value=123';"/> 

Parameters:

table - the table to render the buttons for

buttons - the array of ActionButtons to render

idProperty - the row object identifier property name

parameterName - a parameter name for the row object identifier

See Also:

LinkDecorator(org.apache.click.control.Table, org.apache.click.control.ActionButton, java.lang.String)

LinkDecorator

public LinkDecorator(Table table,
                     ActionButton[] buttons,
                     String idProperty)

Create a new ActionButton table column Decorator with the given ActionButtons array and row object identifier property name. The default linkSeparator for buttons is " ".

Parameters:

table - the table to render the links for

buttons - the array of ActionButtons to render

idProperty - the row object identifier property name

See Also:

LinkDecorator(org.apache.click.control.Table, org.apache.click.control.AbstractLink, java.lang.String)

LinkDecorator

public LinkDecorator(Table table,
                     List<? extends AbstractControl> controls,
                     String idProperty)

Create a new table column Decorator with the given list of AbstractLinks or ActionButtons and row object identifier property name. The default linkSeparator for buttons are " ".

Please note you must provide either AbstractLink objects or ActionButton objects in the controls array, but not a mixture of both.

Parameters:

table - the table to render the links for

controls - the list of AbstractLink or ActionButtons to render

idProperty - the row object identifier property name

See Also:

LinkDecorator(org.apache.click.control.Table, org.apache.click.control.AbstractLink, java.lang.String)

Method Detail

getLinkSeparator

public String getLinkSeparator()

Return the link separator string. The default value is " | ".

Returns:

the link separator string.

setLinkSeparator

public void setLinkSeparator(String value)

Set the link separator string with the given value.

Parameters:

value - the link separator string value

render

public String render(Object row,
                     Context context)

Render the given row object using the links or buttons.

Specified by:

render in interface Decorator

Parameters:

row - the row object to render

context - the request context

Returns:

the rendered links for the given row object and request context

See Also:

Decorator.render(java.lang.Object, org.apache.click.Context)

renderActionLinks

public String renderActionLinks(Object row,
                                Context context)

Render the given row object using the actionLinks array.

This method initializes each link in actionLinks array by invoking initLink(org.apache.click.control.AbstractLink, org.apache.click.Context, java.lang.Object).

This method also renders each link in the array by invoking renderActionLink(org.apache.click.util.HtmlStringBuffer, org.apache.click.control.AbstractLink, org.apache.click.Context, java.lang.Object, java.lang.Object).

Parameters:

row - the row object to render

context - the request context

Returns:

the rendered links for the given row object and request context

renderActionButtons

public String renderActionButtons(Object row,
                                  Context context)

Render the given row object using the actionButtons array.

This method initializes each button in actionButtons array by invoking initButton(org.apache.click.control.ActionButton, org.apache.click.Context, java.lang.Object).

This method also renders each button in the array by invoking renderActionButton(org.apache.click.util.HtmlStringBuffer, org.apache.click.control.ActionButton, org.apache.click.Context, java.lang.Object, java.lang.Object).

Parameters:

row - the row object to render

context - the request context

Returns:

the rendered buttons for the given row object and request context

renderActionLink

protected void renderActionLink(HtmlStringBuffer buffer,
                                AbstractLink link,
                                Context context,
                                Object row,
                                Object value)

Render the link to the specified buffer.

If this method is overridden to add extra parameters to the link, remember to invoke super.renderActionLink so default rendering can continue.

Parameters:

buffer - the specified buffer to render the link output to

link - the link to render

context - the request context

row - the table row being rendered

value - the value of the link

renderActionButton

protected void renderActionButton(HtmlStringBuffer buffer,
                                  ActionButton button,
                                  Context context,
                                  Object row,
                                  Object value)

Render the button to the specified buffer.

If this method is overridden to add extra parameters to the button, remember to invoke super.renderActionButton so default rendering can continue.

Parameters:

buffer - the specified buffer to render the button output to

button - the button to render

context - the request context

row - the table row being rendered

value - the value of the button

See Also:

renderActionLink(org.apache.click.util.HtmlStringBuffer, org.apache.click.control.AbstractLink, org.apache.click.Context, java.lang.Object, java.lang.Object)

initLink

protected void initLink(AbstractLink link,
                        Context context,
                        Object value)

Initialize the link value and parameters.

Parameters:

link - the link to initialize

context - the request context

value - the value of the link

initButton

protected void initButton(ActionButton button,
                          Context context,
                          Object value)

Initialize the button value and parameters.

Parameters:

button - the button to initialize

context - the request context

value - the value of the button