// connect is essentially 'Connect' for either ButtonPress or
// ButtonRelease events.
func connect(xu *xgbutil.XUtil, callback xgbutil.CallbackMouse, evtype int,
win xproto.Window, buttonStr string, sync bool, grab bool) error {
// Get the mods/button first
mods, button, err := ParseString(xu, buttonStr)
if err != nil {
return err
}
// Only do the grab if we haven't yet on this window.
// And if we WANT a grab...
if grab && mouseBindGrabs(xu, evtype, win, mods, button) == 0 {
err := GrabChecked(xu, win, mods, button, sync)
if err != nil {
// If a bad access, let's be nice and give a good error message.
switch err.(type) {
case xproto.AccessError:
return fmt.Errorf("Got a bad access error when trying to bind "+
"'%s'. This usually means another client has already "+
"grabbed this mouse binding.", buttonStr)
default:
return fmt.Errorf("Could not bind '%s' because: %s",
buttonStr, err)
}
}
}
// If we've never grabbed anything on this window before, we need to
// make sure we can respond to it in the main event loop.
var allCb xgbutil.Callback
if evtype == xevent.ButtonPress {
allCb = xevent.ButtonPressFun(runButtonPressCallbacks)
} else {
allCb = xevent.ButtonReleaseFun(runButtonReleaseCallbacks)
}
// If this is the first Button{Press|Release}Event on this window,
// then we need to listen to Button{Press|Release} events in the main loop.
if !connectedMouseBind(xu, evtype, win) {
allCb.Connect(xu, win)
}
// Finally, attach the callback.
attachMouseBindCallback(xu, evtype, win, mods, button, callback)
return nil
}
// Drag is the public interface that will make the appropriate connections
// to register a drag event for three functions: the begin function, the
// step function and the end function.
// The 'grabwin' is the window that the grab is placed on (and therefore the
// window where all button events are redirected to after the drag has started),
// and the 'win' is the window that the initial 'begin' callback is set on.
// In typical use cases, these windows should be the same.
// If 'grab' is false, then no pointer grab is issued.
func Drag(xu *xgbutil.XUtil, grabwin xproto.Window, win xproto.Window,
buttonStr string, grab bool,
begin xgbutil.MouseDragBeginFun, step xgbutil.MouseDragFun,
end xgbutil.MouseDragFun) {
ButtonPressFun(
func(xu *xgbutil.XUtil, ev xevent.ButtonPressEvent) {
DragBegin(xu, ev, grabwin, win, begin, step, end)
}).Connect(xu, win, buttonStr, false, grab)
// If the grab win isn't the dummy, then setup event handlers for the
// grab window.
if grabwin != xu.Dummy() {
xevent.MotionNotifyFun(dragStep).Connect(xu, grabwin)
xevent.ButtonReleaseFun(DragEnd).Connect(xu, grabwin)
}
}
// Initialize attaches the appropriate callbacks to make mouse bindings easier.
// i.e., prep the dummy window to handle mouse dragging events
func Initialize(xu *xgbutil.XUtil) {
xevent.MotionNotifyFun(dragStep).Connect(xu, xu.Dummy())
xevent.ButtonReleaseFun(DragEnd).Connect(xu, xu.Dummy())
}