Swing Hacks

Create a Global Right-Click #57

Chapter 8, Rendering

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HACK

H A C K

#57

Create a Global Right-Click

Hack #57

Give your application a right-click context menu without having to add a

listener to every component.

Oftentimes, an application needs to have a pop-up menu that is accessible

from more than one component. Sometimes the entire window should be

right-clickable. Unfortunately, doing this the normal way in Swing would

require adding a mouse listener to every component in the window, which

isn’t a very appealing solution, especially if your UI code is spread across

many classes. It would be much nicer if there were a single place to add the

context menu. This hack shows how to use a single glass pane to provide a

right-clickable menu to the entire application.

A glass pane is an invisible

JComponent that covers an entire JFrame. The glass

pane can be used to catch events or draw on top of the rest of the applica-

tion. For this hack, we will use a glass pane to capture right-click events and

trigger a pop up, alleviating the need to register a mouse listener with every

component in the frame. The basic idea is for the glass pane to intercept all

mouse events and forward them on to the application, except for the right-

click. Right-clicks will trigger the pop-up menu instead. This way there is

only one listener per frame, instead of potentially hundreds.

To start off, you need a component that has ...