Package org.gnome.gdk

Interface DragSurface.ComputeSizeCallback

All Superinterfaces:

FunctionPointer

Enclosing interface:

DragSurface

Functional Interface:

This is a functional interface and can therefore be used as the assignment target for a lambda expression or method reference.

@FunctionalInterface
public static interface DragSurface.ComputeSizeCallback
extends FunctionPointer

Functional interface declaration of the ComputeSizeCallback callback.

See Also:

• run(org.gnome.gdk.DragSurfaceSize)

Method Summary

Modifier and Type	Method	Description
void	run(DragSurfaceSize size)	Emitted when the size for the surface needs to be computed, when it is present.
default MemorySegment	toCallback(Arena arena)	Creates a native function pointer to the upcall(java.lang.foreign.MemorySegment, java.lang.foreign.MemorySegment) method.
default void	upcall(MemorySegment sourceDragSurface, MemorySegment size)	The upcall method is called from native code.

Method Details

run

void run(DragSurfaceSize size)

Emitted when the size for the surface needs to be computed, when it is present.

This signal will normally be emitted during the native surface layout cycle when the surface size needs to be recomputed.

It is the responsibility of the drag surface user to handle this signal and compute the desired size of the surface, storing the computed size in the Gdk.DragSurfaceSize object that is passed to the signal handler, using DragSurfaceSize.setSize(int, int).

Failing to set a size so will result in an arbitrary size being used as a result.

upcall

default void upcall(MemorySegment sourceDragSurface,
 MemorySegment size)

The upcall method is called from native code. The parameters are marshaled and run(org.gnome.gdk.DragSurfaceSize) is executed.

toCallback

default MemorySegment toCallback(Arena arena)

Creates a native function pointer to the upcall(java.lang.foreign.MemorySegment, java.lang.foreign.MemorySegment) method.

Specified by:

toCallback in interface FunctionPointer

Parameters:

arena - the function pointer will be allocated in this arena

Returns:

the native function pointer