Type Alias cef_life_span_handler_t 

pub type cef_life_span_handler_t = _cef_life_span_handler_t;

Implement this structure to handle events related to browser life span. The functions of this structure will be called on the UI thread unless otherwise indicated.

Aliased Type

#[repr(C)]
pub struct cef_life_span_handler_t {
    pub base: _cef_base_ref_counted_t,
    pub on_before_popup: Option<unsafe extern "C" fn(*mut _cef_life_span_handler_t, *mut _cef_browser_t, *mut _cef_frame_t, *const _cef_string_utf16_t, *const _cef_string_utf16_t, cef_window_open_disposition_t, i32, *const _cef_popup_features_t, *mut _cef_window_info_t, *mut *mut _cef_client_t, *mut _cef_browser_settings_t, *mut *mut _cef_dictionary_value_t, *mut i32) -> i32>,
    pub on_after_created: Option<unsafe extern "C" fn(*mut _cef_life_span_handler_t, *mut _cef_browser_t)>,
    pub do_close: Option<unsafe extern "C" fn(*mut _cef_life_span_handler_t, *mut _cef_browser_t) -> i32>,
    pub on_before_close: Option<unsafe extern "C" fn(*mut _cef_life_span_handler_t, *mut _cef_browser_t)>,
}

Fields

base: _cef_base_ref_counted_t

Base structure.

on_before_popup: Option<unsafe extern "C" fn(*mut _cef_life_span_handler_t, *mut _cef_browser_t, *mut _cef_frame_t, *const _cef_string_utf16_t, *const _cef_string_utf16_t, cef_window_open_disposition_t, i32, *const _cef_popup_features_t, *mut _cef_window_info_t, *mut *mut _cef_client_t, *mut _cef_browser_settings_t, *mut *mut _cef_dictionary_value_t, *mut i32) -> i32>

Called on the UI thread before a new popup browser is created. The |browser| and |frame| values represent the source of the popup request. The |target_url| and |target_frame_name| values indicate where the popup browser should navigate and may be NULL if not specified with the request. The |target_disposition| value indicates where the user intended to open the popup (e.g. current tab, new tab, etc). The |user_gesture| value will be true (1) if the popup was opened via explicit user gesture (e.g. clicking a link) or false (0) if the popup opened automatically (e.g. via the DomContentLoaded event). The |popupFeatures| structure contains additional information about the requested popup window. To allow creation of the popup browser optionally modify |windowInfo|, |client|, |settings| and |no_javascript_access| and return false (0). To cancel creation of the popup browser return true (1). The |client| and |settings| values will default to the source browser’s values. If the |no_javascript_access| value is set to false (0) the new browser will not be scriptable and may not be hosted in the same renderer process as the source browser. Any modifications to |windowInfo| will be ignored if the parent browser is wrapped in a cef_browser_view_t. Popup browser creation will be canceled if the parent browser is destroyed before the popup browser creation completes (indicated by a call to OnAfterCreated for the popup browser). The |extra_info| parameter provides an opportunity to specify extra information specific to the created popup browser that will be passed to cef_render_process_handler_t::on_browser_created() in the render process.

on_after_created: Option<unsafe extern "C" fn(*mut _cef_life_span_handler_t, *mut _cef_browser_t)>

Called after a new browser is created. It is now safe to begin performing actions with |browser|. cef_frame_handler_t callbacks related to initial main frame creation will arrive before this callback. See cef_frame_handler_t documentation for additional usage information.

do_close: Option<unsafe extern "C" fn(*mut _cef_life_span_handler_t, *mut _cef_browser_t) -> i32>

Called when a browser has recieved a request to close. This may result directly from a call to cef_browser_host_t::*close_browser() or indirectly if the browser is parented to a top-level window created by CEF and the user attempts to close that window (by clicking the ‘X’, for example). The do_close() function will be called after the JavaScript ‘onunload’ event has been fired.

An application should handle top-level owner window close notifications by calling cef_browser_host_t::try_close_browser() or cef_browser_host_t::CloseBrowser(false (0)) instead of allowing the window to close immediately (see the examples below). This gives CEF an opportunity to process the ‘onbeforeunload’ event and optionally cancel the close before do_close() is called.

When windowed rendering is enabled CEF will internally create a window or view to host the browser. In that case returning false (0) from do_close() will send the standard close notification to the browser’s top-level owner window (e.g. WM_CLOSE on Windows, performClose: on OS X, “delete_event” on Linux or cef_window_delegate_t::can_close() callback from Views). If the browser’s host window/view has already been destroyed (via view hierarchy tear-down, for example) then do_close() will not be called for that browser since is no longer possible to cancel the close.

When windowed rendering is disabled returning false (0) from do_close() will cause the browser object to be destroyed immediately.

If the browser’s top-level owner window requires a non-standard close notification then send that notification from do_close() and return true (1).

The cef_life_span_handler_t::on_before_close() function will be called after do_close() (if do_close() is called) and immediately before the browser object is destroyed. The application should only exit after on_before_close() has been called for all existing browsers.

The below examples describe what should happen during window close when the browser is parented to an application-provided top-level window.

Example 1: Using cef_browser_host_t::try_close_browser(). This is recommended for clients using standard close handling and windows created on the browser process UI thread. 1. User clicks the window close button which sends a close notification to the application’s top-level window. 2. Application’s top-level window receives the close notification and calls TryCloseBrowser() (which internally calls CloseBrowser(false)). TryCloseBrowser() returns false so the client cancels the window close. 3. JavaScript ‘onbeforeunload’ handler executes and shows the close confirmation dialog (which can be overridden via CefJSDialogHandler::OnBeforeUnloadDialog()). 4. User approves the close. 5. JavaScript ‘onunload’ handler executes. 6. CEF sends a close notification to the application’s top-level window (because DoClose() returned false by default). 7. Application’s top-level window receives the close notification and calls TryCloseBrowser(). TryCloseBrowser() returns true so the client allows the window close. 8. Application’s top-level window is destroyed. 9. Application’s on_before_close() handler is called and the browser object is destroyed. 10. Application exits by calling cef_quit_message_loop() if no other browsers exist.

Example 2: Using cef_browser_host_t::CloseBrowser(false (0)) and implementing the do_close() callback. This is recommended for clients using non-standard close handling or windows that were not created on the browser process UI thread. 1. User clicks the window close button which sends a close notification to the application’s top-level window. 2. Application’s top-level window receives the close notification and: A. Calls CefBrowserHost::CloseBrowser(false). B. Cancels the window close. 3. JavaScript ‘onbeforeunload’ handler executes and shows the close confirmation dialog (which can be overridden via CefJSDialogHandler::OnBeforeUnloadDialog()). 4. User approves the close. 5. JavaScript ‘onunload’ handler executes. 6. Application’s do_close() handler is called. Application will: A. Set a flag to indicate that the next close attempt will be allowed. B. Return false. 7. CEF sends an close notification to the application’s top-level window. 8. Application’s top-level window receives the close notification and allows the window to close based on the flag from #6B. 9. Application’s top-level window is destroyed. 10. Application’s on_before_close() handler is called and the browser object is destroyed. 11. Application exits by calling cef_quit_message_loop() if no other browsers exist.

on_before_close: Option<unsafe extern "C" fn(*mut _cef_life_span_handler_t, *mut _cef_browser_t)>

Called just before a browser is destroyed. Release all references to the browser object and do not attempt to execute any functions on the browser object (other than IsValid, GetIdentifier or IsSame) after this callback returns. cef_frame_handler_t callbacks related to final main frame destruction will arrive after this callback and cef_browser_t::IsValid will return false (0) at that time. Any in-progress network requests associated with |browser| will be aborted when the browser is destroyed, and cef_resource_request_handler_t callbacks related to those requests may still arrive on the IO thread after this callback. See cef_frame_handler_t and do_close() documentation for additional usage information.