The context menu is not a control itself - it is part of existing controls. Context menus are supported by the following controls:
TEXTGRID2
TEXTGRIDSSS2
TREENODE2
CLIENTTREE
FIELD
All these controls have items that are represented by corresponding objects on the server side:
For the text grid controls, each row of the grid is represented by a
certain object on the server side that is managed inside a
TEXTGRIDCollection.
For the tree controls, each node of the tree is represented by a
certain object (derived from NODEInfo) that is managed
inside a TREECollection.
When the user right-clicks on an item, the method
reactOnContextMenuRequest() is called inside the
item's server-side object. When the user right-clicks in a FIELD control for
which "myfield" has been defined with the
valueprop property, the default name of the called
method is reactOnContextMenuMyfield. In principle,
your server-side implementation could do anything as reaction inside the
implementation of the method - i.e. you do not have to open a context menu, but
you can also do every other thing that you are able to do inside an adapter
implementation.
To open a context menu, you proceed as follows:
You define a tree collection.
You add menu nodes to the tree collection - exactly in the same way as you do it with a normal MENU control.
You pass the tree collection to the adapter via its method
showPopupMenu().
This document covers the following topics:
There is no special specification necessary inside the layout definition
of the corresponding TEXTGRID2/ TEXTGRIDSSS2 control. All you have to do is to
implement the reactOnContextMenuRequest() method
inside the class representing the items of the grid:
public class MenuAdapter
extends Model
{
// ------------------------------------------------------------------------
// inner classes
// ------------------------------------------------------------------------
/** class used for pop-up menu. */
public class MyMenuNodeInfo
extends MENUNODEInfo
{
public MyMenuNodeInfo(String text) { super(text); }
public MyMenuNodeInfo(String text, String image) { super(text, image); }
public void reactOnSelect()
{
outputMessage("S", "Menu Item \"" + getText() + "\" selected!");
}
}
/** class represents one row within the text grid. */
public class Line
{
String m_name;
CTimeStamp m_htmlChange;
CTimeStamp m_xmlChange;
public Line(String name, CTimeStamp xmlChange, CTimeStamp htmlChange)
{
m_name = name;
m_xmlChange = xmlChange;
m_htmlChange = htmlChange;
}
public String getName() { return m_name; }
public CTimeStamp getHtmlChange() { return m_htmlChange; }
public CTimeStamp getXmlChange() { return m_xmlChange; }
/** This method will be called if the line will be clicked with
* the right mouse button.*/
public void reactOnContextMenuRequest()
{
// prepare the appropriate popu menu content
TREECollection menu = new TREECollection();
menu.addTopNode(new MyMenuNodeInfo(
"Open in Layout Painter",
"../HTMLBasedGUI/images/open.gif"),true);
menu.addTopNode(new MyMenuNodeInfo(
"Generate Adapter Code",
"../HTMLBasedGUI/images/java.gif"),true);
menu.addTopNode(new MyMenuNodeInfo(
"Maintain Literals",
"../HTMLBasedGUI/images/literals.gif"),true);
menu.addTopNode(new MyMenuNodeInfo(
"&SEPARATOR"),true);
menu.addTopNode(new MyMenuNodeInfo(
"Remove (XML & HTML)",
"../HTMLBasedGUI/images/remove.gif"),true);
// open the poup menu
showPopupMenu(menu);
}
}
...
...
...
...
...
}
Pay attention: the showPopupMenu() method is
provided by the class Adapter - in the implementation
example, it is directly accessed from the class Line.
The class Line is an inner class and consequently has
full access to all the methods of its surrounding class.
The implementation of a context menu in the tree is absolutely the same
as with a text grid - this time you have to implement the
reactOnContextMenuRequest() method inside the class
representing one tree node.