1. In the Eclipse 3.x model, views must be subclasses of ViewPart
. In the Eclipse 4.x model, parts do not need to have an explicit superclass.
2. In the Eclipse 3.x model, views are registered via an org.eclipse.ui.views
extension point in the plugin.xml
.
3. The two arguments that most SWT objects have are a Composite
parent and an integer flags field.
4. When a widget is disposed, it will have its native resources released to the operating system. Any subsequent actions will throw an SWTException
with a Widget is disposed message.
5. The Canvas has many drawing operations; to draw a circle, use drawArc()
, and specify a full orbit.
6. To receive drawing events, a PaintListener
must be created and associated with the control by using the addPaintListener
method.
7. UI updates not on the UI thread will generate an SWTException
with an Invalid thread access
error.
8. To perform an update on a widget from a non-UI thread, use the asyncExec
or syncExec
methods from Display
(3.x) or UISynchronize
(4.x) to wrap a Runnable
or lambda that will run on the UI thread.
9. SWT.DEFAULT
is used to indicate default options in the flags parameter that is passed to the construction of an SWT widget.
10. Create a RowData
object with the given size, and associate it with each widget.
1. Resource leaks occur when an SWT Resource
is acquired from the OS but then not returned to it via a dispose
method prior to the object being garbage collected.
2. The different types of resources are Color
, Cursor
, Font
, GC
, Image
, Path
, Pattern
, Region
, TextLayout
, and Transform
.
3. Run the Eclipse instance in tracing mode, with org.eclipse.ui/debug
and org.eclipse.ui/trace/graphics
set, specified in a debug file, and launched with -debug
.
4. Use the Display.getDeviceData()
to get the objects
arrays, and iterate through them.
5. The right way is to register a DisposeListener
with the view, and the wrong way is to override the dispose
method.
1. Using the setFocus
method to set the focus on a particular widget.
2. Invoking redraw
will allow the widget to redraw itself.
3. The combo
can have a SelectionListener
associated with it.
4. The widgetDefaultSelected
is what is called when the default value is used, typically an empty value.
1. Use the Tray
and TrayItem
widgets.
2. The NO_TRIM
means don't draw the edges of the window, or the close/maximize/minimize buttons.
3. Use setAlpha
to control a widget's transparency, including shells.
4. setRegion
with a path describing the shape.
5. A Group
allows you to group things together with a standard item.
6. Most composites use a null layout manager by default; it's only shells and dialogs that have a non-default value.
7. Use a ScrolledComposite
.
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