Erlang -- wxWebView

# wxWebView

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Module

wxWebView

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Module Summary

Functions for wxWebView class

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Description

This control may be used to render web (HTML / CSS / javascript) documents. It is designed to allow the creation of multiple backends for each port, although currently just one is available. It differs from wxHtmlWindow in that each backend is actually a full rendering engine, Trident on MSW and Webkit on macOS and GTK. This allows the correct viewing of complex pages with javascript and css.

Backend Descriptions

Par: The IE backend uses Microsoft's Trident rendering engine, specifically the version used by the locally installed copy of Internet Explorer. As such it is only available for the MSW port. By default recent versions of the WebBrowser control, which this backend uses, emulate Internet Explorer 7. This can be changed with a registry setting by wxWebView::MSWSetEmulationLevel() see this article for more information. This backend has full support for custom schemes and virtual file systems.

Par: The Edge (Chromium) backend uses Microsoft's Edge WebView2. It is available for Windows 7 and newer. The following features are currently unsupported with this backend: virtual filesystems, custom urls, find.

This backend is not enabled by default, to build it follow these steps:

Par: Under GTK the WebKit backend uses WebKitGTK+. The current minimum version required is 1.3.1 which ships by default with Ubuntu Natty and Debian Wheezy and has the package name libwebkitgtk-dev. Custom schemes and virtual files systems are supported under this backend, however embedded resources such as images and stylesheets are currently loaded using the data:// scheme.

Par: Under GTK3 the WebKit2 version of WebKitGTK+ is used. In Ubuntu the required package name is libwebkit2gtk-4.0-dev and under Fedora it is webkitgtk4-devel. All wxWEBVIEW_WEBKIT features are supported except for clearing and enabling / disabling the history.

Par: The macOS WebKit backend uses Apple's WebView class. This backend has full support for custom schemes and virtual file systems.

Asynchronous Notifications

Many of the methods in wxWebView are asynchronous, i.e. they return immediately and perform their work in the background. This includes functions such as loadURL/2 and reload/2. To receive notification of the progress and completion of these functions you need to handle the events that are provided. Specifically wxEVT_WEBVIEW_LOADED notifies when the page or a sub-frame has finished loading and wxEVT_WEBVIEW_ERROR notifies that an error has occurred.

Virtual File Systems and Custom Schemes

wxWebView supports the registering of custom scheme handlers, for example file or http. To do this create a new class which inherits from wxWebViewHandler (not implemented in wx), where wxWebHandler::GetFile() returns a pointer to a wxFSFile (not implemented in wx) which represents the given url. You can then register your handler with RegisterHandler() (not implemented in wx) it will be called for all pages and resources.

wxWebViewFSHandler (not implemented in wx) is provided to access the virtual file system encapsulated by wxFileSystem (not implemented in wx). The wxMemoryFSHandler (not implemented in wx) documentation gives an example of how this may be used.

wxWebViewArchiveHandler (not implemented in wx) is provided to allow the navigation of pages inside a zip archive. It supports paths of the form: scheme:///C:/example/docs.zip;protocol=zip/main.htm

Since: 2.9.3

See: wxWebViewHandler (not implemented in wx), wxWebViewEvent

This class is derived (and can use functions) from: wxControl wxWindow wxEvtHandler

wxWidgets docs: wxWebView

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Events

Event types emitted from this class: webview_navigating, webview_navigated, webview_loaded, webview_error, webview_newwindow, webview_title_changed

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Data Types

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wxWebView() = wx:wx_object()

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Exports

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new(Parent, Id) -> wxWebView()

### Types

Parent = wxWindow:wxWindow()
Id = integer()

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new(Parent, Id, Options :: [Option]) -> wxWebView()

### Types

Parent = wxWindow:wxWindow()
Id = integer()
Option =
{url, unicode:chardata()} |
{pos, {X :: integer(), Y :: integer()}} |
{size, {W :: integer(), H :: integer()}} |
{backend, unicode:chardata()} |
{style, integer()}

Factory function to create a new wxWebView using a wxWebViewFactory (not implemented in wx).

Return: The created wxWebView, or NULL if the requested backend is not available

Since: 2.9.5

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getCurrentTitle(This) -> unicode:charlist()

### Types

This = wxWebView()

Get the title of the current web page, or its URL/path if title is not available.

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getCurrentURL(This) -> unicode:charlist()

### Types

This = wxWebView()

Get the URL of the currently displayed document.

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getPageSource(This) -> unicode:charlist()

### Types

This = wxWebView()

Get the HTML source code of the currently displayed document.

Return: The HTML source code, or an empty string if no page is currently shown.

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getPageText(This) -> unicode:charlist()

### Types

This = wxWebView()

Get the text of the current page.

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isBusy(This) -> boolean()

### Types

This = wxWebView()

Returns whether the web control is currently busy (e.g. loading a page).

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isEditable(This) -> boolean()

### Types

This = wxWebView()

Returns whether the web control is currently editable.

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loadURL(This, Url) -> ok

### Types

This = wxWebView()
Url = unicode:chardata()

Load a web page from a URL.

Note: Web engines generally report errors asynchronously, so if you wish to know whether loading the URL was successful, register to receive navigation error events.

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print(This) -> ok

### Types

This = wxWebView()

Opens a print dialog so that the user may print the currently displayed page.

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reload(This) -> ok

### Types

This = wxWebView()

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reload(This, Options :: [Option]) -> ok

### Types

This = wxWebView()
Option = {flags, wx:wx_enum()}

Reload the currently displayed URL.

Note: The flags are ignored by the edge backend.

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runScript(This, Javascript) -> Result

### Types

Result = {Res :: boolean(), Output :: unicode:charlist()}
This = wxWebView()
Javascript = unicode:chardata()

Runs the given JavaScript code.

JavaScript code is executed inside the browser control and has full access to DOM and other browser-provided functionality. For example, this code will replace the current page contents with the provided string.

If output is non-null, it is filled with the result of executing this code on success, e.g. a JavaScript value such as a string, a number (integer or floating point), a boolean or JSON representation for non-primitive types such as arrays and objects. For example:

This function has a few platform-specific limitations:

Also notice that under MSW converting JavaScript objects to JSON is not supported in the default emulation mode. wxWebView implements its own object-to-JSON conversion as a fallback for this case, however it is not as full-featured, well-tested or performing as the implementation of this functionality in the browser control itself, so it is recommended to use MSWSetEmulationLevel() to change emulation level to a more modern one in which JSON conversion is done by the control itself.

Return: true if there is a result, false if there is an error.

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setEditable(This) -> ok

### Types

This = wxWebView()

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setEditable(This, Options :: [Option]) -> ok

### Types

This = wxWebView()
Option = {enable, boolean()}

Set the editable property of the web control.

Enabling allows the user to edit the page even if the contenteditable attribute is not set. The exact capabilities vary with the backend being used.

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setPage(This, Html, BaseUrl) -> ok

### Types

This = wxWebView()
Html = BaseUrl = unicode:chardata()

Set the displayed page source to the contents of the given string.

Note: When using wxWEBVIEW_BACKEND_IE you must wait for the current page to finish loading before calling setPage/3. The baseURL parameter is not used in this backend and the edge backend.

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stop(This) -> ok

### Types

This = wxWebView()

Stop the current page loading process, if any.

May trigger an error event of type wxWEBVIEW_NAV_ERR_USER_CANCELLED. TODO: make wxWEBVIEW_NAV_ERR_USER_CANCELLED errors uniform across ports.

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canCopy(This) -> boolean()

### Types

This = wxWebView()

Returns true if the current selection can be copied.

Note: This always returns true on the macOS WebKit backend.

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canCut(This) -> boolean()

### Types

This = wxWebView()

Returns true if the current selection can be cut.

Note: This always returns true on the macOS WebKit backend.

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canPaste(This) -> boolean()

### Types

This = wxWebView()

Returns true if data can be pasted.

Note: This always returns true on the macOS WebKit backend.

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copy(This) -> ok

### Types

This = wxWebView()

Copies the current selection.

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cut(This) -> ok

### Types

This = wxWebView()

Cuts the current selection.

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paste(This) -> ok

### Types

This = wxWebView()

Pastes the current data.

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enableContextMenu(This) -> ok

### Types

This = wxWebView()

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enableContextMenu(This, Options :: [Option]) -> ok

### Types

This = wxWebView()
Option = {enable, boolean()}

Enable or disable the right click context menu.

By default the standard context menu is enabled, this method can be used to disable it or re-enable it later.

Since: 2.9.5

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isContextMenuEnabled(This) -> boolean()

### Types

This = wxWebView()

Returns true if a context menu will be shown on right click.

Since: 2.9.5

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canGoBack(This) -> boolean()

### Types

This = wxWebView()

Returns true if it is possible to navigate backward in the history of visited pages.

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canGoForward(This) -> boolean()

### Types

This = wxWebView()

Returns true if it is possible to navigate forward in the history of visited pages.

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clearHistory(This) -> ok

### Types

This = wxWebView()

Clear the history, this will also remove the visible page.

Note: This is not implemented on the WebKit2GTK+ backend.

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enableHistory(This) -> ok

### Types

This = wxWebView()

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enableHistory(This, Options :: [Option]) -> ok

### Types

This = wxWebView()
Option = {enable, boolean()}

Enable or disable the history.

This will also clear the history.

Note: This is not implemented on the WebKit2GTK+ backend.

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goBack(This) -> ok

### Types

This = wxWebView()

Navigate back in the history of visited pages.

Only valid if canGoBack/1 returns true.

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goForward(This) -> ok

### Types

This = wxWebView()

Navigate forward in the history of visited pages.

Only valid if canGoForward/1 returns true.

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clearSelection(This) -> ok

### Types

This = wxWebView()

Clears the current selection.

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deleteSelection(This) -> ok

### Types

This = wxWebView()

Deletes the current selection.

Note that for wxWEBVIEW_BACKEND_WEBKIT the selection must be editable, either through SetEditable or the correct HTML attribute.

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getSelectedSource(This) -> unicode:charlist()

### Types

This = wxWebView()

Returns the currently selected source, if any.

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getSelectedText(This) -> unicode:charlist()

### Types

This = wxWebView()

Returns the currently selected text, if any.

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hasSelection(This) -> boolean()

### Types

This = wxWebView()

Returns true if there is a current selection.

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selectAll(This) -> ok

### Types

This = wxWebView()

Selects the entire page.

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canRedo(This) -> boolean()

### Types

This = wxWebView()

Returns true if there is an action to redo.

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canUndo(This) -> boolean()

### Types

This = wxWebView()

Returns true if there is an action to undo.

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redo(This) -> ok

### Types

This = wxWebView()

Redos the last action.

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undo(This) -> ok

### Types

This = wxWebView()

Undos the last action.

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find(This, Text) -> integer()

### Types

This = wxWebView()
Text = unicode:chardata()

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find(This, Text, Options :: [Option]) -> integer()

### Types

This = wxWebView()
Text = unicode:chardata()
Option = {flags, wx:wx_enum()}

Finds a phrase on the current page and if found, the control will scroll the phrase into view and select it.

Return: If search phrase was not found in combination with the flags then wxNOT_FOUND is returned. If called for the first time with search phrase then the total number of results will be returned. Then for every time its called with the same search phrase it will return the number of the current match.

Note: This function will restart the search if the flags wxWEBVIEW_FIND_ENTIRE_WORD or wxWEBVIEW_FIND_MATCH_CASE are changed, since this will require a new search. To reset the search, for example resetting the highlights call the function with an empty search phrase. This always returns wxNOT_FOUND on the macOS WebKit backend.

Since: 2.9.5

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canSetZoomType(This, Type) -> boolean()

### Types

This = wxWebView()
Type = wx:wx_enum()

Retrieve whether the current HTML engine supports a zoom type.

Return: Whether this type of zoom is supported by this HTML engine (and thus can be set through setZoomType/2).

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getZoom(This) -> wx:wx_enum()

### Types

This = wxWebView()

Get the zoom level of the page.

See getZoomFactor/1 to get more precise zoom scale value other than as provided by wxWebViewZoom.

Return: The current level of zoom.

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getZoomType(This) -> wx:wx_enum()

### Types

This = wxWebView()

Get how the zoom factor is currently interpreted.

Return: How the zoom factor is currently interpreted by the HTML engine.

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setZoom(This, Zoom) -> ok

### Types

This = wxWebView()
Zoom = wx:wx_enum()

Set the zoom level of the page.

See setZoomFactor/2 for more precise scaling other than the measured steps provided by wxWebViewZoom.

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setZoomType(This, ZoomType) -> ok

### Types

This = wxWebView()
ZoomType = wx:wx_enum()

Set how to interpret the zoom factor.

Note: invoke canSetZoomType/2 first, some HTML renderers may not support all zoom types.

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getZoomFactor(This) -> number()

### Types

This = wxWebView()

Get the zoom factor of the page.

Return: The current factor of zoom.

Since: 3.1.4

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setZoomFactor(This, Zoom) -> ok

### Types

This = wxWebView()
Zoom = number()

Set the zoom factor of the page.

Note: zoom scale in IE will be converted into wxWebViewZoom levels for wxWebViewZoomType of wxWEBVIEW_ZOOM_TYPE_TEXT.

Since: 3.1.4

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isBackendAvailable(Backend) -> boolean()

### Types

Backend = unicode:chardata()

Allows to check if a specific backend is currently available.

Since: 3.1.4