grab


Description:

[ Version ( deprecated = true , deprecated_since = "3.20." , since = "3.0" ) ]
public GrabStatus grab (Window window, GrabOwnership grab_ownership, bool owner_events, EventMask event_mask, Cursor? cursor, uint32 time_)

Warning: grab is deprecated since 3.20..

Grabs the device so that all events coming from this device are passed to this application until the device is ungrabbed with ungrab, or the window becomes unviewable.

Note:

Use grab instead.

This overrides any previous grab on the device by this client.

Note that this and window need to be on the same display.

Device grabs are used for operations which need complete control over the given device events (either pointer or keyboard). For example in GTK+ this is used for Drag and Drop operations, popup menus and such.

Note that if the event mask of an X window has selected both button press and button release events, then a button press event will cause an automatic pointer grab until the button is released. X does this automatically since most applications expect to receive button press and release events in pairs. It is equivalent to a pointer grab on the window with owner_events set to true .

If you set up anything at the time you take the grab that needs to be cleaned up when the grab ends, you should handle the EventGrabBroken events that are emitted when the grab ends unvoluntarily.

Parameters:

this

a Device. To get the device you can use gtk_get_current_event_device or get_device if the grab is in reaction to an event. Also, you can use get_client_pointer but only in code that isn’t triggered by a Event and there aren’t other means to get a meaningful Device to operate on.

window

the Window which will own the grab (the grab window)

grab_ownership

specifies the grab ownership.

owner_events

if false then all device events are reported with respect to window and are only reported if selected by event_mask. If true then pointer events for this application are reported as normal, but pointer events outside this application are reported with respect to window and only if selected by event_mask. In either mode, unreported events are discarded.

event_mask

specifies the event mask, which is used in accordance with owner_events.

cursor

the cursor to display while the grab is active if the device is a pointer. If this is null then the normal cursors are used for window and its descendants, and the cursor for window is used elsewhere.

time_

the timestamp of the event which led to this pointer grab. This usually comes from the Event struct, though gdk_current_time can be used if the time isn’t known.

Returns:

gdk_grab_success if the grab was successful.