Wt Release notes

Release 3.1.2 (March 26, 2010)

This release contains mostly bug fixes, and a few new features.

A) New classes:

WShadow

Class representing a drop shadow effect (see below).

Dbo/backend/Postgres

A Postgres backend has landed, contributed by Hilary Cheng.

B) Main new features in existing classes:

WBoxLayout, WGridLayout

Addition of horizontal and vertical splitter support (resize handles to allow the user to adjust the layout), sponsored by Eurofer. The new API methods are setResizable(), setColumnResizable() and setRowResizable()

WCalendar

Improved the API to allow custom cell rendering, and custom handling of selection. We have also made the API for selection consistent with other widgets (like WTreeView), deprecating the old API.

WDateTime

Added toPosixTime() and fromPosixTime() methods to interoperate with boost::posix_time::ptime.

WFormWidget

Added a setEmptyText() method to implement a label inside a line edit or text area.

WPainter

Added a setShadow() method which defines a drop shadow to be used for subsequent drawing actions.

WResource

Added a setInternalPath() method which allow a resource to be deployed at a deterministic and "pretty" URL.

WString

Added constructors that take a std::locale for interpreting a narrow string in a given locale.

WWidget

Added setLayoutSizeAware() and layoutSizeChanged() methods which allow a widget to react to layout size changes.

Http::Request

Added access to the request method().

Http::Response

Added a setStatus() method to modify the response status.

Dbo::Session

Added support for schema qualified tables, in Session::mapClass() and the joinTable specified in hasMany().
Added API for dropping the schema: dropTables().
Added support for arbitrary queries in Session::query(), including queries that do not return result or do not select from tables.

Dbo::field()

Allow size suggestion for std::string and WString mappings

Dbo::SqlConnection, Dbo::SqlStatement

Added support for floating point types, binary data (using std::vector<unsigned char>) and date and date/time types.
Added methods for return dialect-specific information.
Added properties API.

Dbo::sql_value_traits

Added support for backend-specific type mapping.

(internal) DomElement

Performance improvements in serializing the widgets to HTML and/or JavaScript

Built-in httpd

Added a configuration option --max-request-size to limit the size of a POST instead of the built-in default of 40 MB
Added a configuration option --max-memory-request-size to limit the size of a POST that is handed in-memory. Bigger POSTs are handled using a spool file.

Release 3.1.1 (February 17, 2010)

The minimum boost version is now 1.36.

This release handles mostly bug fixes, with as most visible change an update of the polished theme, which is now considered complete.

A) Security fixes:

Possible XSS vulnerability

Fixed a possible XSS attack where a user follows a link to a Wt web application, taking advantage of unchecked insertions of the URL when redirecting to the canonical page.

Possible UTF-8 vulnerability

Form values and JSignal arguments received from the browser are now checked for sane UTF-8 encoding.

B) New classes:

Dbo/Dbo

An optional base class for a database object, providing access to its id() and session().

C) Main new features in existing classes:

WCanvasPaintDevice

Now implements native text rendering on Firefox and latest Chrome and Safari browsers

WInPlaceEdit

Added a setEmptyText() method which sets the text to be displayed when value is empty.

WPopopMenu

Added an exec(WWidget *location, Orientation orientation) method which popups the menu besides another widget.

WSuggestionPopup

This class is now also style by the CSS theme.

WTemplate

Avoids now rerendering of already bound widgets when the template is rerendered.

WTree, WTreeNode, WTreeTable, WTreeTableNode

These widgets are now theme-aware, and tree decoration styling is provided by the theme. The setImagePack() APIs are now no-ops

WWidget

Added positionAt() method which positions a widget (absolutely) besides another widget.

Chart/WAxis>

Added a setLabelFont() method.

Http/Request

Added serverName(), serverPort(), path(), pathInfo(), queryString(), urlScheme(), in(), contentType(), contentLength(), userAgent() and clientAddress() methods which expose information form the HTTP request to WResources.

D) Build changes:

XML_FEATURES

This CMake option has been removed, and Mini-XML has been replaced by a modified RapidXML xml parser (mostly because of the hard-to-interpret Mini-XML license), but there are also nice performance improvements.

Release 3.1.0 (December 29, 2009)

This release contains several new features and classes, after a long period of stabilization that happened before the 3.0.0 release.

A) New classes:

WAggregateProxyModel

A model that provides support for drilling down through columns, supported by WTreeView.

WCombinedLocalizedStrings

Combines different localized strings implementations.

WDateTime

Combines a calendar date (WDate) and a clock time (WTime).

WTemplate

Use an XHTML fragment as a template, with variables that are place holders for strings or other widgets. See the blog example of how this class can be used to simplify HTML/CSS based layout of widgets and contents.

WTime

Represents a clock time (0-24 hours).

Wt::Dbo

An Object Relational Mapping library. See the tutorial here.

B) Main new features in existing classes:

Signal

Added a template connect() method which may be given any function object, providing also support for the (future) c++1x lambda functions.

WCanvasDevice

Several optimizations to output more concise JavaScript.

WPaintedWidget

When width and/or height is not set using resize(), the widget will now properly react to layout management when put into a layout manager, triggering a server-side rerendering when needed.

WSlider

A sliderMoved() signal was added which is fired whenever the slider is moved (but not yet released).

WWidget

Added a find() method which searches the widget hierachy for a widget with a particular objectName().

WServer

Added an addResource() method to bind static resources to particular URLs (i.e. resources that are not bound to a specific session).

Ext::Container

Will now properly react to layout management from a layout that is set for a WContainerWidget.

Ext::FormField

Added changed(), blurred() and focussed() signals.

Chart::WAxis

Added setAutoLimits() and autoLimits() methods to configure which limits are to be determined based on the data, and which are explicitly set.

Chart::WDataSeries

Added the setHidden() and hidden() methods to enable or disable a data series. Added setBarWidth() and barWidth() methods to set the width of a bar (useful mostly for scatter plots). Added setMarkerSize() and markerSize() methos.

Chart::WCartesianChart

Use MarkerPenColorRole and MarkerBrushColorRole to override colors for makers on a per data point basis. Added mapFromDevice() and mapToDevice() methods for mapping device coordinates to chart coordinates and vice-versa

C) API Changes:

WSlider

Not really an API change, but the vertical slider is now showing the maximum value at its top side, not its bottom side.

Chart::WAxis

The minimum() and maximum() methods will now return the calculated minimum and maximum value when they are to be automatically calculated based on the data, configured using setAutoLimits()

D) Build changes:

XML_FEATURES

A new configuration option, XML_FEATURES, was added which allows the library to be built without MiniXML (and disabling fatures that require Mini-XML support). This configuration option is likely to be removed again in future versions.

Documentation

A doc directive was added, which uses doxygen and asciidoc tools to generate the reference documentation and tutorial.

Tests

Automated tests were added for non-interactive functionality, and are built by default.

Release 3.0.0 (November 3, 2009)

This release contains mostly bug fixes, build improvements and documentation improvements compared to the latest pre-release (2.99.5).

Most build improvements are related to finding the boost libraries. Previously, Wt used a custom script, since CMake versions < 2.6 did not provide a good enough script for finding boost. Starting with this release, when using CMake 2.6 or later, Wt will use the script that comes with CMake. You can still fall back to the script that comes with Wt, which is still used for older versions of CMake, by defining one of the BOOST_COMPILER or BOOST_VERSION variables.

A) New classes:

B) Main new features in existing classes:

WDialog

It is now possible to have multiple modal dialogs, and nested recursive event loops.

WWidget

The setDisabled() method moved up from WFormWidget to WWidget.

JSlot

The exec() method now passes object and event to the JavaScript event handler.

C) API Changes:

WResource

The handling of changes to the resource has been sanitized. A new method, setChanged() was added which must be called to notify users of the resource that the resource was changed. In addition to the existing generateUrl() which generates a new URL, a method was added which merely returns the existing URL: url(). With these improvements, a resource can effictively be shared by many view widgets and updated with the minimum of bandwidth usage.

Release 2.99.5 (September 1, 2009)

This release contains mostly bug fixes. The previous release (2.99.4) contains some critical bugs that cause mayhem on IE, and a regression with server push.

Release 2.99.4 (August 27, 2009)

!! This release contains bugs that render it unusable on IE !!

This release contains mostly bug fixes and back-end improvements. The most exciting new feature is the addition of a new bootstrap method, which implements progressive enhancements (starting with a plain HTML page, and then upgrading it to an AJAX page if the browser has support), see also the documentation.

A) New classes:

WTableView

This is a simple MVC View class that renders tabular data in the most straight forward way using an HTML table element

B) Main new features in existing classes:

Ext::ToolBar

Added insert() methods.

WApplication

Added an enableAjax() method which notifies the application that a session is being enhanced with AJAX capabilities when using the progressive bootstrap method.

WWidget

Added an enableAjax() method which enhanced the widget with AJAX capabilities when using the progressive bootstrap method.

WCssDecorationStyle

Add support for custom cursors.

WServer

For FastCGI deployments, the proxy process which directs FastCGI requests to the correct session process is now also multi-threaded.

C) API Changes:

The WApplication::notify() behavior changed.

Previously during a request, this method was called multiple times during event propagation and rendering of the application. Now, the method is called exactly once for each request. In this way, it becomes a useful entry point to also manage resource usage during (and inbetween) requests.

Release 2.99.3 (July 24, 2009)

This release contains mostly bug fixes and small feature improvements. The most notable change that might affect existing applications is a simplified internal path API behavior.

A) New classes:

WAbstractItemDelegate and WItemDelegate

WAbstractItemDelegate is a helper class used by WTreeView (and in the future perhaps other view classes) to render contents. The standard implementation, WItemDelegate maintains the default implementation that was previously integrated in WTreeView. The delegate will be responsible for editing features in WTreeView in the future, and in fact, you can already implement a custom item delegate that does editing if you cannot wait for it!

Test/WTestEnvironment

WTestEnvironment is an environment class which is useful for (unit) test-cases: it allows the instantiation of a WApplication so that you may include widgets in unit tests.

B) Main new features in existing classes:

C) API Changes:

change of WApplication::internalPathChanged() semantics.

The old behavior was that a single internal path change caused by the user (e.g. by moving forward/backword through his browser history) would cause repetitive invocations of internalPathChanged() with different arguments. The underlying idea was that this would make it easier to have the handling of internal path changes distributed over different objects. It caused however more problems than it solved. The new behavior is now that it is invoked exactly one time, and the argument is simply the new internal path.

Release 2.99.2 (May 29, 2009)

This release contains mostly build improvements, bug fixes, and API cleanups.

A) New classes:

Http/Client

Client is a utility class to bootstrap a new Wt application.

B) Main new features in existing classes:

Ext::FormField

Add setFocus() method.

Ext::ToolBar

Added an addStretch() method (contributed by David Galicia).

Http::Response

Added a continuation() method.

WCheckBox

Add support for tri-state checkboxes. These are also supported by item models and WTreeView.

WDialog

Support for non-modal dialogs and interactive moving.

WFormWidget

New methods setReadOnly() and isReadOnly().

WGridLayout

Support a row stretch value of -1, which is like 0 but will still manage the height of cells (allowing their contents to fill the entire cell).

WPaintDevice

Support update rendering (not erasing the current canvas) using paint flags.

C) API Changes:

WFileUpload::isUploaded() was deprecated

The name was not covering its actual behavior: instead of checking whether a file has been uploaded, it returns whether true when a call to upload() is not needed. You should replace any call to isUploaded() with the new method !canUpload() (note the inversion!.

Release 2.99.1 (Mar 20, 2009)

This release contains only build improvements, bug fixes, and API cleanups.

Release 2.99.0 (Mar 4, 2009)

This release is a preview for Wt 3.0.0. Many things have changed both in the internals and the API. This is the first release that provides several API changes which are not backward compatible (some of which were post-poned until now). Please read the following notes carefully, especially sections C) and D), to understand what changes to expect and how to adapt existing applications.

Support for the C++ boost library < 1.35 has been dropped: Wt now requires at least boost >= 1.35.0.

A) New classes:

WFlags

WFlags is a utility class that provides a type-safe ORing of enum flags. It is used everywhere in the Wt API where previously an int was used to allow enums to be ORed together.

WGoogleMap

This is a widget, contributed by Richard Ulrich, that displays a Google map.

Http::Request, Http::Response, Http::ResponseContinuation and Http::UploadedFile

These are utility classes which model an HTTP request and response and that are used in the new WResource API.

B) Main new features in existing classes:

WApplication::enableUpdates()

Server-initiated updates (aka "server push") has been reimplemented and now works reliably in all situations, including in the presence of intermediate proxies. The dependency on the 3rd party JS orbited library has been removed and replaced with a simple XHR-based solution.

WButtonGroup

Various methods were added: id's may be associated with a specific radio buttons, which may be used to identify a particular button.

WDatePicker

Is now easier to use because of a sensible default constructor that also creates the line edit using a WDateValidator, and creates the icon which is associated with the popup.

WFileResource

Uses the continuation support in the new WResource API to transmit the file in chunks.

WLength

WLength::Auto was added, is a synonym for WLength()

WSuggestionPopup

Is now also an MVC View widget, reading its data from a WAbstractItemModel

WTable

New method setHeaderCount() to specify the number of first rows or columns that should be rendered as an HTML table header (<th>).

WWidget

New virtual method rerender() which allows a widget to prepare itself before rendering (and defer internal changes until that time). A widget may ask to be rerendered using askRerender()

Widget no longer inherits from WResource, but instead inherits directly from WObject. It was simply a bad idea, and not useful for anything.

C) Changes that break existing applications:

1) Signals are no longer public members

Instead, they are now accessor member functions: e.g. WInteractWidget::clicked has been renamed to WInteractWidget::clicked(). This has as major benefit that signals can be created on-demand, which leads to drastically lower memory usage and signifcant speedups especially on embedded systems.

The change requires that everywhere in your code where you access a signal, you will need to change to add parentheses. For consistency, you may also want to use the same convention for your own widget classes that define signals.

2) WResource

The API has been redesigned and greatly simplified. If you are implementing your own resources, then you will need to redesign your implementation. The new API is simpler (requires only one virtual method to be implemented) and more powerful, providing support for continuations to serve large resources without blocking a thread or requiring large memory usage.

In addition, resources have better thread-safety: they are now by default reentrant (requests for a single resource may be handled concurrently) and they are protected from concurrently being destroyed by the main event loop.

3) WValidator

The signature for the virtual validate() method was changed: parameter pos which was ignored anyway has been removed.

4) WEnvironment

The methods getArgument() and arguments() were renamed to respectively getParameter() and getParameterMap(). The signature for getParameter() is also different as it returns a pointer to a string, which is 0 when the parameter is not defined, instead of the olde behaviour of throwing an exception. There is a new method that allows to read all values for a parameter, getParameterValues()

5) WModelIndex

The 20-byte SHA1 hash based internal pointer has been removed again as the object increase and overhead could not be justified.

D) Deprecated API that was removed:

WApplication::applicationName()

Use WApplication::internalPath() instead.

WApplication::setState()

Use WApplication::setInternalPath() instead.

WApplication::state()

Use WApplication::internalPath() instead.

WApplication::stateChanged

Use WApplication::internalPathChanged() instead.

WRegExpValidator::WRegExpValidator(const boost::regex&)

Use the WRegExpValidator(const WString&) constructor instead.

WPainterPath::drawArc(..., width, height, ...)

An elliptical arc segment could not be support on all devices.

WTable::numRows()

Use WTable::rowCount().

WTable::numColumns()

Use WTable::columnCount() instead.

WText::setFormatting() and WText::formatting()

Use WText::setTextFormat() and WText::textFormat() instead.

Release 2.2.3 (Jan 26, 2009)

This release is a maintenance release, with mostly bug fixes and feature improvements.

A) Main new features in existing classes:

WAbstractItemModel:

const char * data in boost::any is now also supported.

WAbstractProxyModel:

Implemented toRawIndex() and fromRawIndex() so that indexes can be recovered when the model's layout is changed, if the underlying model provides implementations for toRawIndex() and fromRawIndex().

WComboBox:

Also supports StyleClassRole data role for items

WDialog:

New method setTitleBarEnabled() to disable the default title bar.

WMenu:

New method removeItem(), only works when rendered as a list.

WTabWidget:

New method removeTab().

WTreeView:

• New method setColumn1Fixed() to fix the first column while scrolling horizontally through the other columns.
• New method setColumnFormat() to control formatting of data.
• New method setColumnBorder() to set the internal column border color.
• New method setColumnResizeEnabled() to disable resize handles.
• The view now also reacts correctly to insertion and removal of model columns.

B) New examples

gitmodel:

An example that demonstrates how to implement a custom abstract item model.

treeview-dragdrop:

An example that demonstrates drag and drop support in WTreeView.

C) Changes that break backward compatibility

WApplication:

useStyleSheet() only supports a subset of IE condition strings, since the string is now parsed by Wt rather than by IE (when dynamically loading stylesheets, the comment-syntax does not work reliably).

Release 2.2.2 (Dec 1, 2008)

As of now, we will also be listing noteworthy new API features, even if they are no concern for backwards compatibility.

A) New classes:

WPopupMenu, WPopupMenuItem:

A popup menu, which you would typically use to present a context menu.

WAbstractProxyModel, WSortFilterProxyModel:

Proxy models, which present data from a source model in a different way.

WLoadingIndicator, WDefaultLoadingIndicator, WOverlayLoadingIndicator:

Customizable loading indicators.

B) Main new features in existing classes:

WTreeView, WAbstractItemModel:

The WAbstractItemModel interface was extended to allow handling of drag & drop events, and WTreeView now is able to start dragging and handle dropping of item selections and other data.

JSignal:

You can now pass the original (keyboard/mouse) JavaScript event as a parameter to custom signals.

WTreeView:

access mouse event in itemClicked, doubleClicked and mouseWentDown signals.

WServer:

Support for widget-set mode, allowing a Wt application to be embedded in an existing web page/application.

C) Changes that break backward compatibility

This release does not contain changes that break existing applications.

Release 2.2.1 (Nov 3, 2008)

This release is as usually a mix of bug fixes, improvements and new features.

We have made a significant change to the MVC system, which will break existing program code in case you have implemented your own models (i.e. deriving from WAbstractItemModel) or views widgets (i.e. components that listen to model changes).

The WAbstractItemModel interface was changed to support hierarchical models. This means that most methods will now take an extra parameter that specifies the parent WModelIndex, and also all signals have now this extra parameter. Because the parameter has a default value of WModelIndex() which corresponds to the top level parent, the API is largely backwards compatible when merely using the model. It is only those classes that reimplement the interface, or listen to signal events, that are affected.

The immediate benefit of the new WAbstracItemModel interface is that it allows us to implement View widgets like the new WTreeView widget.

Release 2.2.0 (Sept 12, 2008)

This release has a rather substantial rewrite (and simplification) of Wt's bootstrapping process. In the past, Wt used a frameset trick to be able to load the AJAX-based skeleton when JavaScript was available. Isntead, now, the entire AJAX-based stuff is loaded directly into the bootstrap page. A benefit of the new approach is that we avoid iframe tricks, which have been deprecated from strict HTML and XHTML. But, it was in fact motivated in the first place to support all major browsers for a new internal path API. This new API allows to fully support URL changes and bookmarks in a unified way (i.e. it works equally when the browser supports AJAX, no JavaScript, or is a bot such as google bot).

As a consequence, this release contains the following changes that may break your application:

• WMenu::enableBrowserHistory() and WMenu::browserHistoryId() have been removed, use the new methods WMenu::setInternalPathEnabled() and WMenu::setInternalBasePath()
• WMenuItem has been reorganized, and if you have specialized WMenuItem you will need to adapt your reimplementation to the new virtual interface. In the new interface, you need to reimplement WMenuItem::createItemWidget() and WMenuItem::updateItemWidget() allowing you to react to item changes (internal path or text). The default implementation now always uses a WAnchor.
• WApplication::setState(), WApplication::state() and WApplication::stateChanged have been deprecated. It is stronly advised that you use the new internal path API instead. This does require you to treat different parts of the state as a file hierarchy. See the WApplication::setInternalPath() documentation.

The following methods have been deprecated (but are still supported):

• WTable::numRows() has been renamed to WTable::rowCount().
• WTable::numColumns() has been renamed to WTable::columnCount().

Release 2.1.5 (July 25, 2008)

Wt now installs its include files in a Wt/ subdirectory. You may want to change your build files to pick up this new include directory, or, change your code to scope the include files to look like #include<Wt/WLineEdit> instead of #include<WLineEdit>

This release contains the following changes that may break your application:

• WText will validate XHTML text when it is set to the widget. The old behaviour was to validate only before rendering. The change was needed to be able to react to XML parse errors. As a consequence if you are creating a WText with text that is not valid XML, followed by a call setFormatting(WText::PlainFormatting), you should change this now to use the new WText constructor which takes the TextFormat as a new argument: new WText(text, Wt::PlainText, parentWidget)
• WContainerWidget::setLayout(WLayout *layout, bool fitWidth, bool fitHeight) has been replaced with the more generic WContainerWidget::setLayout(WLayout *layout, int alignment).

The following methods and enumerations have been deprecated (but are still supported):

• enum WText::Formatting has been renamed to Wt::TextFormat. The old values map as follows on new values:
  • WText::XHTMLFormatting becomes Wt::XHTMLText;
  • WText::XHTMLUnsafeFormatting becomes Wt::XHTMLUnsafeText
  • WText::PlainFormatting becomes Wt::PlainText
• WText::setFormatting() has been renamed to WText::setTextFormat() and WText::formatting() has been renamed to WText::textFormat().

Release 2.1.4 (July 4, 2008)

The following has changed for building Wt:

• The CMake variable CONFIGURATION (which defaulted to /etc/wt/wt_config.xml) is no longer used, but instead there is now a CONFIGDIR (/etc/wt/) which is used to store configuration files.

The following has changed in the wt_config.xml file:

• The <valgrind-path> setting for the FCGI connector may now be a command-line including arguments

This release should not contain changes that may break your application.

Release 2.1.3 (May 20, 2008)

This release should not contain changes that may break your application.

Release 2.1.2 (April 14, 2008)

The following changes may break your application build:

• WTreeNode::expanded() has been renamed to WTreeNode::isExpanded().

Release 2.1.1 (April 10, 2008)

This release should not break any of your applications, but we did deprecate some methods and enumeration types. You are advised to migrate to the replacements methods since we will discontinue support for the older ones in the future.

The following methods and enumerations have been deprecated:

• enum SelectionUnit has been renamed to SelectionBehavior. The old values map as follows on new values: CellSelection becomes SelectItems; RowSelection becomes SelectRows.
• WWidget::setOffset(int sides, WLength) is deprecated, and the new method is WWidget::setOffsets(WLength, int sides): the argument order has been switched to be consistent with the method signature of setMargin() and setPadding().
• WResource::suggestFilename() has been renamed to WResource::suggestFileName().

The following changes affect run-time behaviour:

• WTreeNode now supports a policy for when to show a child count indication. The old behaviour was to always show the child count. Now, by default this option is disabled. Use WTreeNode::setChildCountPolicy(Enabled) to get the old behaviour back, if you wish.

Release 2.1.0

The library dependencies have changed slightly.

To build Wt 2.1.0, you need:

• CMake 2.4 or later
• boost 1.34.1 (boost 1.33.1 might should still work, but is not recommended)
• asio 0.3.9: either the boost or non-boost version (only for the http connector)
• optionally, openssl for HTTPS support (only for the http connector)
• optionally, libz for gzip compression support (only for the http connector)
• fcgi library, including C++ bindings (libfcgi++)(only for the fcgi connector)

Furthermore, the Wt::Ext library has been upgraded and now wraps around the extjs 2.x library, instead of extjs 1.x.

Some API changes may need a porting effort:

• Ext::ProgressDialog: doesn't show by default, you need to call show() to show the dialog.
• Ext::ContentPanel, Ext::BorderLayout have been removed. They have been replaced with a stand-alone layout system, that may manage contents in an Ext::Container. The layout system provides WBorderLayout and several other layout managers.
• WSignalMapper has been expanded to allow mapping of signals with an extra argument, which is passed to the mapped signal. Because of this, the signature of the class has been expanded with an extra template argument. If you have forward declarations to WSignalMapper, you will need to modify these too (or simply include WSignalMapper).
• WAnchor: no longer uses a WLabel internally, and the label-releated methods have been removed.

Release 2.0.5

• WDialog (and WMessageBox) usage changed, and is now more like Qt. When you are not using WDialog::exec() or WMessageBox::show(...), then you must explictly show() the dialog to show it. You can now also hide() the dialog if you want.
• Moved several enums from within classes to the Wt namespace. This is likely to break your code at compile time when you are using one. The fix is to remove the class scope from the enum type or value.
  • WScrollArea::Orientation -> Wt::Orientation
  • WMenu::Orientation -> Wt::Orientation
  • WMessageBox::StandardButton -> Wt::StandardButton
  • WMessageBox::Icon -> Wt::Icon

Release 2.0.4

This release adds a few new features:

• WComboBox (and WSelectionBox) now use a WAbstractItemModel in a more flexible model/view system.
• Stylesheets may be browser-conditional (by Patrick Fischer)
• wthttpd may serve custom error pages (by Patrick Fischer)
• WResource can now access HTTP GET or POST query arguments. This will break your code (at compile time) if you have implemented your own WResource, since the signature of the streamResourceData() method has been changed to pass the arguments map as a second parameter.

Release 2.0.1

This release fixes some build-related problems, as well as smaller bugs. The main improvement in this release is related to use of Wt in resource-constrained embedded systems.

The most visible change is that the dependency on the Xerces C++ XML library was dropped in favour of the much smaller Mini-XML library. The draw-back is a reduction of supported character encodings to only UTF8 and UTF16, next to the default locale character encoding (which is typically an 8-bit flavour).

When using the built-in httpd, you can now disable support for SSL at compile time, freeing a number of SSL-related dependencies.

In the API, more comparison operators (== and !=) were added to WString, and a WViewWidget was added for simple MVC widgets (with the main purpose to reduce session-state at the server).

Release 2.0.0

This release contains numerous changes which are likely to cause some porting effort for Wt 1.1.x applications to work properly.

If you are upgrading from a 1.99.x release, you will notice that some of these notes have actually evolved, especially with respect to WString and unicode support.

Here is a list of changes with respect to Wt 1.1.x that are likely to require your attention, and some tips on how to do the porting.

1) Namespace Wt

All Wt classes are now inside the namespace Wt.

To handle this change, you will need to:

• Wrap forward declarations to Wt widgets in header files inside a Wt namespace, or #include <WFwdDeclarations>
• and scope all Wt classes with Wt::,
• or import the Wt namespace: using namespace Wt;

2) WString

Previously, most widgets offered double methods that either used a std::string for literal text, or a WMessage for localized text.

In the new release, widgets use Wt::WString for both literal and localized text. WString offers unicode support for both literal as well as localized text. To create a literal string, simply assign or construct a Wt::WString from that string. The strings supported or both narrow and wide C and C++ strings. UTF8 encoded narrow strings may also be converted. To create a localized string, use one of the static methods WString::tr(const std::string key) and WWidget::tr(const std::string key).

To help with legacy code, WMessage is now a typedef for WString, but is deprecated and should not be used in new code. Unfortunately, the constructors WMessage(const char *text) and WMessage(const std::string text), changed meaning! While previously they took a key to construct a localized message, they now take a literal text (the exact opposite!), since they are in fact plain WString() constructors. As a consequence your application will display key values instead of resolving those values (but will not break entirely).

The new approach offers the benefit of only requiring one method signature for both literal and localizable text. This not only simplifies our work, but more importantly by using WString for displayed text in the API of your own widgets, localization (including the automatic language switching) comes automatically and is decided on by the user of your widget.

Fortunately, there is a straightforward trick to handle most consequences of this change:

• Replace WMessage(...) with tr(...),
• add .value() when using the result of functions such as WText::text(),
• change your own classes to use WString wherever they expect some text that will be displayed, instead of std::string or WMessage.

3) Wide string API

Since Wt 2.0.0, the API for Wt has been changed to use WString instead of C++ narrow strings. WString supports both narrow and wide strings, and provides conversion between both. It does not provide string operations, however, and instead acts as a string container. You should convert to a C++ string type to perform operations. You should also not use WString outside of the user interface part of your application.

4) No more wmain()

Previously, the Wt library implemented the main(int argc, char **argv) function, and called a wmain() function which created the WApplication instance.

Wt 2.0.0 allows multiple applications to run within a single process. Therefore, the WApplication::exec() approach was no longer feasible. The new approach requires that:

• your main function should look like this:

  int main(int argc, char **argv)
  {
    return Wt::WRun(argc, argv, &createApplication);
  }
  

• where createApplication is a function of the following signature:

  Wt::WApplication *createApplication(const Wt::WEnvironment& env)
  {
    // return a new application object.
  }
  

5) Configuration in /etc/wt/wt_config.xml

Wt 2.0.0 uses a configuration file for a number of settings that could previously be configured at build time of the library, or in the API. The latter functions are:

• WApplication::setMaximumRquestSize()
• WApplication::setIdleTimeout()

6) Removed obsolete classes

Wt 2.0.0 removed a number of classes that were still in the widget tree, but have been obsoleted by more flexible classes:

• WAbstractTab, WButtonTab, and WTabWidget are obsoleted by the more flexible WMenu.

7) Deprecate boost::regex from WRegExpValidator API

The constructor and methods that takes a boost::regex object in the WRegExpValidator API have been deprecated, to remove the dependency on boost from the public API. You should consider the std::string based construtor and method instead.

8) WObject::emit() has been removed.

Since Wt 1.99.1, we have removed WObject::emit() function. Instead, you may simply call the signal with its arguments, or use the explicit emit method (recommended).

To adapt your code, you should:

• Replace all emit(MySignal(...)) with MySignal(...) or MySignal.emit(...)

9) WResource::streamResourceData() signature has changed.

Since Wt 2.0.0, WResource::streamResourceData() returns a boolean value which indicates if all data has been streamed. If you have reimplemented WResource for your applications, you must update the signature and return true.

The change is relevant only within the new server-push support that is now in Wt 2.0.0. This allows you to continuously append to the content of a resource.

10) Rename of WJavascriptSlot to JSlot.

Release 1.1.7

Release 1.1.6

Release 1.1.5

Release 1.1.4

• The dependency for libxml++ (and its large number of dependencies) has been dropped, and replaced by Xerces-C++ (which has no further dependencies).
• Wt programs need to link against libwtfcgi.so, instead of libwt.so. In the future Wt will also support different web-connnector systems besides FastCGI.
• The signatures of wmain() and WApplication constructor have changed: new signatures are:
  • int wmain(const WEnvironment& env)
  • WApplication::WApplication(const WEnvironment& env)

Other changes:

• Support for unicode is implemented, but perhaps needs more testing by non-Western people ? Only UTF-8 is supported currently.
• Addition of a WTimer class -- see mission example.
• Many bug fixes which should make Wt more robust against illegal CGI requests (which are ignored), and now Wt should exit cleanly in more (all?) circumstances.
• Addition of feed-back for pending AJAX requests (does not work yet on IE).
• Support for style sheets is improved: now inline decoration styles will override style sheet styles. See hangman or treelist examples.
• The browser can be redirected to a new page. This is useful when the application is terminated -- or to change during the application from HTTP to HTTPS and back.
• WValidationStatus API has changed -- less complicated now.