File: event_observer.h

package info (click to toggle)
chromium 120.0.6099.224-1~deb11u1
  • links: PTS, VCS
  • area: main
  • in suites: bullseye
  • size: 6,112,112 kB
  • sloc: cpp: 32,907,025; ansic: 8,148,123; javascript: 3,679,536; python: 2,031,248; asm: 959,718; java: 804,675; xml: 617,256; sh: 111,417; objc: 100,835; perl: 88,443; cs: 53,032; makefile: 29,579; fortran: 24,137; php: 21,162; tcl: 21,147; sql: 20,809; ruby: 17,735; pascal: 12,864; yacc: 8,045; lisp: 3,388; lex: 1,323; ada: 727; awk: 329; jsp: 267; csh: 117; exp: 43; sed: 37
file content (34 lines) | stat: -rw-r--r-- 1,154 bytes parent folder | download | duplicates (6) 
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
 
// Copyright 2018 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#ifndef UI_EVENTS_EVENT_OBSERVER_H_
#define UI_EVENTS_EVENT_OBSERVER_H_

#include "ui/events/events_export.h"

namespace ui {

class Event;

// EventObservers are notified of events but are unable to modify the events or
// mark them as handled before they are dispatched to EventHandlers.
//
// Window service clients may use this interface for observation of events that
// target the window manager or other clients. Clients should limit the types
// and duration of observation, as there is a system-wide perf/battery penalty,
// especially for frequently occurring events, like mouse moves. Events with
// targets outside of the client's scope will have a null target.
class EVENTS_EXPORT EventObserver {
 public:
  // Called for all events matching the requested event types.
  // The root location of located events is always in screen coordinates.
  virtual void OnEvent(const Event& event) = 0;

 protected:
  virtual ~EventObserver() {}
};

}  // namespace ui

#endif  // UI_EVENTS_EVENT_OBSERVER_H_