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Class com.trumphurst.controls.ContainerKeyTracker

java.lang.Object
   |
   +----com.trumphurst.controls.ContainerFocusTracker
           |
           +----com.trumphurst.controls.ContainerKeyTracker

public class ContainerKeyTracker

extends ContainerFocusTracker

To use, just create a tracker, passing it the Container you want to deal with.

Note that this extends ContainerFocusTracker, which corrects a bug in Java 1.1 where focus is not handled correctly.

By default, plain letter and number keys are only intercepted from Buttons and Checkboxes. Control and Function keys, Escape, and Enter are intercepted from all components. Note that the interception of the Tab and Enter keys doesn't work in TextComponents. For TextComponents, the Control key is required in conjunction with the Tab or Enter key.

The default behaviour recognises the following components ...

Button

• A button labelled "OK" is pressed if the user hits the Enter key.
• A button labelled "Cancel" is pressed if the user hits the Escape key.
• A button labelled "Help" is pressed if the user hits the F1 key.
• Any other button is pressed if the first upper case letter of its label is pressed.

Checkbox

A Checkbox is checked if the first upper case letter of its label is pressed.

Label

The focus is moved to the next focussable component after a Label if the first upper case letter of its label is pressed.

If there are duplicate components that would use the same key, that key is ignored.

Of course, you can modify this default behaviour, by programmatically adding or removing links between a particular key and a Component. You can also turn key trapping and/or key reception on and off for a particular component, or for a whole class of Component. You can also turn the default behaviour on and off.

ContainerKeyTracker(Container)

ContainerKeyTracker(Container, boolean)

addComponent(Component)

keyPressed(KeyEvent)

Handle key events which a component does not want.

removeComponent(Component)

 public ContainerKeyTracker(Container c,
                            boolean defaultBehaviour)

 public ContainerKeyTracker(Container c)

 public void keyPressed(KeyEvent e)

Handle key events which a component does not want. These events are passed on manually by the ComponentInfo attached to the Component which is the source of the event.

 protected void addComponent(Component c)

Overrides:

addComponent in class ContainerFocusTracker

 protected void removeComponent(Component c)

Overrides:

removeComponent in class ContainerFocusTracker

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