Package org.gnome.gtk

Class DropTarget.Builder<B extends DropTarget.Builder<B>>

java.lang.Object

org.javagi.gobject.Builder<B>

org.gnome.gobject.GObject.Builder<B>

org.gnome.gtk.EventController.Builder<B>

org.gnome.gtk.DropTarget.Builder<B>

Type Parameters:

B - the type of the Builder that is returned

All Implemented Interfaces:

BuilderInterface

Enclosing class:

DropTarget

public static class DropTarget.Builder<B extends DropTarget.Builder<B>>
extends EventController.Builder<B>

Inner class implementing a builder pattern to construct a GObject with properties.

Constructor Summary

Constructors

Modifier	Constructor	Description
protected	Builder()	Default constructor for a Builder object.

Method Summary

Modifier and Type	Method	Description
DropTarget	build()	Finish building the DropTarget object.
B	onAccept(DropTarget.AcceptCallback handler)	Emitted on the drop site when a drop operation is about to begin.
B	onDrop(DropTarget.DropCallback handler)	Emitted on the drop site when the user drops the data onto the widget.
B	onEnter(DropTarget.EnterCallback handler)	Emitted on the drop site when the pointer enters the widget.
B	onLeave(DropTarget.LeaveCallback handler)	Emitted on the drop site when the pointer leaves the widget.
B	onMotion(DropTarget.MotionCallback handler)	Emitted while the pointer is moving over the drop target.
B	setActions(Set<DragAction> actions)	The GdkDragActions that this drop target supports.
B	setActions(DragAction... actions)	The GdkDragActions that this drop target supports.
B	setFormats(ContentFormats formats)	The GdkContentFormats that determine the supported data formats.
B	setPreload(boolean preload)	Whether the drop data should be preloaded when the pointer is only hovering over the widget but has not been released.

Methods inherited from class org.gnome.gtk.EventController.Builder

setName, setPropagationLimit, setPropagationPhase

Methods inherited from class org.gnome.gobject.GObject.Builder

onNotify

Methods inherited from class org.javagi.gobject.Builder

addBuilderProperty, connect, connect, connectSignals, getArena, getNames, getValues

Methods inherited from class java.lang.Object

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

Constructor Details

Builder

protected Builder()

Default constructor for a Builder object.

Method Details

build

public DropTarget build()

Finish building the DropTarget object. This will call GObject.withProperties(org.gnome.glib.Type, java.lang.String[], org.gnome.gobject.Value[]) to create a new GObject instance, which is then cast to DropTarget.

Overrides:

build in class EventController.Builder<B extends DropTarget.Builder<B>>

Returns:

a new instance of DropTarget with the properties that were set in the Builder object.

setActions

public B setActions(Set<DragAction> actions)

The GdkDragActions that this drop target supports.

Parameters:

actions - the value for the actions property

Returns:

the Builder instance is returned, to allow method chaining

setFormats

public B setFormats(ContentFormats formats)

The GdkContentFormats that determine the supported data formats.

Parameters:

formats - the value for the formats property

Returns:

the Builder instance is returned, to allow method chaining

setPreload

public B setPreload(boolean preload)

Whether the drop data should be preloaded when the pointer is only hovering over the widget but has not been released.

Setting this property allows finer grained reaction to an ongoing drop at the cost of loading more data.

The default value for this property is false to avoid downloading huge amounts of data by accident.

For example, if somebody drags a full document of gigabytes of text from a text editor across a widget with a preloading drop target, this data will be downloaded, even if the data is ultimately dropped elsewhere.

For a lot of data formats, the amount of data is very small (like GDK_TYPE_RGBA), so enabling this property does not hurt at all. And for local-only Drag-and-Drop operations, no data transfer is done, so enabling it there is free.

Parameters:

preload - the value for the preload property

Returns:

the Builder instance is returned, to allow method chaining

setActions

public B setActions(DragAction... actions)

The GdkDragActions that this drop target supports.

Parameters:

actions - the value for the actions property

Returns:

the Builder instance is returned, to allow method chaining

onAccept

public B onAccept(DropTarget.AcceptCallback handler)

Emitted on the drop site when a drop operation is about to begin.

If the drop is not accepted, false will be returned and the drop target will ignore the drop. If true is returned, the drop is accepted for now but may be rejected later via a call to DropTarget.reject() or ultimately by returning false from a Gtk.DropTarget::drop handler.

The default handler for this signal decides whether to accept the drop based on the formats provided by the drop.

If the decision whether the drop will be accepted or rejected depends on the data, this function should return true, the Gtk.DropTarget:preload property should be set and the value should be inspected via the ::notify:value signal, calling DropTarget.reject() if required.

Parameters:

handler - the signal handler

Returns:

the Builder instance is returned, to allow method chaining

See Also:

• DropTarget.AcceptCallback.run(org.gnome.gdk.Drop)

onDrop

public B onDrop(DropTarget.DropCallback handler)

Emitted on the drop site when the user drops the data onto the widget.

The signal handler must determine whether the pointer position is in a drop zone or not. If it is not in a drop zone, it returns false and no further processing is necessary.

Otherwise, the handler returns true. In this case, this handler will accept the drop. The handler is responsible for using the given value and performing the drop operation.

Parameters:

handler - the signal handler

Returns:

the Builder instance is returned, to allow method chaining

See Also:

• DropTarget.DropCallback.run(org.gnome.gobject.Value, double, double)

onEnter

public B onEnter(DropTarget.EnterCallback handler)

Emitted on the drop site when the pointer enters the widget.

It can be used to set up custom highlighting.

Parameters:

handler - the signal handler

Returns:

the Builder instance is returned, to allow method chaining

See Also:

• DropTarget.EnterCallback.run(double, double)

onLeave

public B onLeave(DropTarget.LeaveCallback handler)

Emitted on the drop site when the pointer leaves the widget.

Its main purpose it to undo things done in Gtk.DropTarget::enter.

Parameters:

handler - the signal handler

Returns:

the Builder instance is returned, to allow method chaining

See Also:

• DropTarget.LeaveCallback.run()

onMotion

public B onMotion(DropTarget.MotionCallback handler)

Emitted while the pointer is moving over the drop target.

Parameters:

handler - the signal handler

Returns:

the Builder instance is returned, to allow method chaining

See Also:

• DropTarget.MotionCallback.run(double, double)