CefKeyboardHandler

Header: cef_keyboard_handler.h
Category: Browser Handlers

Overview

User-implemented handler interfaces returned from CefClient and registered with CefBrowserHost.

CefKeyboardHandler

Source File: include/cef_keyboard_handler.h

Process / Thread Context: Browser Process / UI Thread (class comment: "The

Purpose: User-implemented interface to handle keyboard events before they

Methods

`bool OnPreKeyEvent(CefRefPtr<CefBrowser> browser, const CefKeyEvent& event, CefEventHandle os_event, bool* is_keyboard_shortcut)`

Parameters:

browser: The browser receiving the event.
event: CefKeyEvent describing the keyboard event.
os_event: The OS-specific event message (e.g. MSG on Windows), if any.
is_keyboard_shortcut: (Out) Set to true if the event will be handled in OnKeyEvent as a keyboard shortcut. Only meaningful when returning false.

Return Value: Return true if your handler consumed the event (renderer will not see it). Return false to let the renderer handle it normally; if you set *is_keyboard_shortcut = true while returning false, CEF will route the event to OnKeyEvent afterward (deferred shortcut handling).

Usage Instruction: Use for global hotkeys / accelerator tables that should take precedence over page content (e.g. Ctrl+O for open file, F5 to refresh when the page doesn't already handle it). The is_keyboard_shortcut pattern lets you defer decision until after the page has had a chance to handle the key (so you don't double-process).

Threading Constraint: Called on the UI thread.

`bool OnKeyEvent(CefRefPtr<CefBrowser> browser, const CefKeyEvent& event, CefEventHandle os_event)`

Parameters:

browser: The browser receiving the event.
event: CefKeyEvent describing the keyboard event.
os_event: The OS-specific event message, if any.

Return Value: Return true if your handler consumed the event. Return false for default handling.

Usage Instruction: Fires after the renderer and page JavaScript have had a chance to handle the event. Only called when OnPreKeyEvent returned false with *is_keyboard_shortcut = true (or as otherwise scheduled). Use to implement hotkeys that the page did not handle.

Threading Constraint: Called on the UI thread.

Usage Example

cpp

#include "include/cef_keyboard_handler.h"
#include "include/cef_client.h"

class MyKeyboardHandler : public CefKeyboardHandler {
 public:
  bool OnPreKeyEvent(CefRefPtr<CefBrowser> browser,
                     const CefKeyEvent& event,
                     CefEventHandle os_event,
                     bool* is_keyboard_shortcut) override {
    // Pre-check: intercept Ctrl+L to focus the URL bar immediately.
    if (event.type == KEYEVENT_RAWKEYDOWN &&
        event.windows_key_code == 76 /* 'L' */ &&
        (event.modifiers & EVENTFLAG_CONTROL_DOWN)) {
      // FocusUrlBar();  // your code
      return true;
    }
    // Defer F5 to OnKeyEvent so the page has a chance first.
    if (event.type == KEYEVENT_RAWKEYDOWN &&
        event.windows_key_code == 116 /* VK_F5 */) {
      *is_keyboard_shortcut = true;
      return false;
    }
    return false;
  }

  bool OnKeyEvent(CefRefPtr<CefBrowser> browser,
                  const CefKeyEvent& event,
                  CefEventHandle os_event) override {
    if (event.type == KEYEVENT_RAWKEYDOWN &&
        event.windows_key_code == 116 /* VK_F5 */) {
      browser->Reload();
      return true;
    }
    return false;
  }

  IMPLEMENT_REFCOUNTING(MyKeyboardHandler);
};

class MyClient : public CefClient {
 public:
  CefRefPtr<CefKeyboardHandler> GetKeyboardHandler() override {
    return new MyKeyboardHandler();
  }
};

CefKeyboardHandler ​

Overview ​