WebKitUserContentManager: WebKit2GTK+ Reference Manual

## WebKitUserContentManager WebKitUserContentManager — Manages user-defined content which affects web pages. |

## Functions

WebKitUserContentManager * | webkit_user_content_manager_new ()
void | webkit_user_content_manager_add_style_sheet ()
void | webkit_user_content_manager_remove_all_style_sheets ()
void | webkit_user_content_manager_add_script ()
void | webkit_user_content_manager_remove_all_scripts ()
gboolean | webkit_user_content_manager_register_script_message_handler ()
void | webkit_user_content_manager_unregister_script_message_handler ()

## Signals

void | script-message-received | Has Details

## Types and Values

struct | WebKitUserContentManager

## Object Hierarchy

        GObject
        ╰── WebKitUserContentManager

## Description

Using a WebKitUserContentManager user CSS style sheets can be set to be injected in the web pages loaded by a WebKitWebView, by `webkit_user_content_manager_add_style_sheet()`.

To use a WebKitUserContentManager, it must be created using `webkit_user_content_manager_new()`, and then passed to `webkit_web_view_new_with_user_content_manager()`. User style sheets can be created with `webkit_user_style_sheet_new()`.

User style sheets can be added and removed at any time, but they will affect the web pages loaded afterwards.

## Functions

### webkit_user_content_manager_new ()

    WebKitUserContentManager *
    webkit_user_content_manager_new (void);

Creates a new user content manager.

#### Returns

A WebKitUserContentManager

Since: 2.6

### webkit_user_content_manager_add_style_sheet ()

    void
    webkit_user_content_manager_add_style_sheet
                                   (WebKitUserContentManager *manager,
                                    WebKitUserStyleSheet *stylesheet);

Adds a WebKitUserStyleSheet to the given WebKitUserContentManager. The same WebKitUserStyleSheet can be reused with multiple WebKitUserContentManager instances.

#### Parameters

manager | A WebKitUserContentManager |
stylesheet | A WebKitUserStyleSheet |

Since: 2.6

### webkit_user_content_manager_remove_all_style_sheets ()

    void
    webkit_user_content_manager_remove_all_style_sheets
                                   (WebKitUserContentManager *manager);

Removes all user style sheets from the given WebKitUserContentManager.

#### Parameters

manager | A WebKitUserContentManager |

Since: 2.6

### webkit_user_content_manager_add_script ()

    void
    webkit_user_content_manager_add_script
                                   (WebKitUserContentManager *manager,
                                    WebKitUserScript *script);

Adds a WebKitUserScript to the given WebKitUserContentManager. The same WebKitUserScript can be reused with multiple WebKitUserContentManager instances.

#### Parameters

manager | A WebKitUserContentManager |
script | A WebKitUserScript |

Since: 2.6

### webkit_user_content_manager_remove_all_scripts ()

    void
    webkit_user_content_manager_remove_all_scripts
                                   (WebKitUserContentManager *manager);

Removes all user scripts from the given WebKitUserContentManager

#### Parameters

manager | A WebKitUserContentManager |

Since: 2.6

### webkit_user_content_manager_register_script_message_handler ()

    gboolean
    webkit_user_content_manager_register_script_message_handler
                                   (WebKitUserContentManager *manager,
                                    const gchar *name);

Registers a new user script message handler. After it is registered, scripts can use `window.webkit.messageHandlers.<name>.postMessage(value)` to send messages. Those messages are received by connecting handlers to the “script-message-received” signal. The handler name is used as the detail of the signal. To avoid race conditions between registering the handler name, and starting to receive the signals, it is recommended to connect to the signal *before* registering the handler name:

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    WebKitWebView *view = webkit_web_view_new ();
    WebKitUserContentManager *manager = webkit_web_view_get_user_content_manager ();
    g_signal_connect (manager, "script-message-received::foobar",
                      G_CALLBACK (handle_script_message), NULL);
    webkit_user_content_manager_register_script_message_handler (manager, "foobar");

Registering a script message handler will fail if the requested name has been already registered before.

#### Parameters

manager | A WebKitUserContentManager |
name | Name of the script message channel |

#### Returns

`TRUE` if message handler was registered successfully, or `FALSE` otherwise.

Since: 2.8

### webkit_user_content_manager_unregister_script_message_handler ()

    void
    webkit_user_content_manager_unregister_script_message_handler
                                   (WebKitUserContentManager *manager,
                                    const gchar *name);

Unregisters a previously registered message handler.

Note that this does *not* disconnect handlers for the “script-message-received” signal, they will be kept connected, but the signal will not be emitted unless the handler name is registered again.

See also `webkit_user_content_manager_register_script_message_handler()`

#### Parameters

manager | A WebKitUserContentManager |
name | Name of the script message channel |

Since: 2.8

## Types and Values

### struct WebKitUserContentManager

    struct WebKitUserContentManager;

## Signal Details

### The `“script-message-received”` signal

    void
    user_function (WebKitUserContentManager *manager,
                   WebKitJavascriptResult   *js_result,
                   gpointer                  user_data)

This signal is emitted when JavaScript in a web view calls

`window.webkit.messageHandlers.<name>.postMessage()`, after registering `<name>` using

webkit_user_content_manager_register_script_message_handler()

#### Parameters

manager | the WebKitUserContentManager |
js_result | the WebKitJavascriptResult holding the value received from the JavaScript world. |
user_data | user data set when the signal handler was connected. |

Flags: Has Details

Since: 2.8