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A few doc fixes to BApplication and BHandler.

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* Since <em> is used for parameters we can't use it for emphasis.
* Add \a in a few places it was missing to indicate a parameter.
* Change \a to a \c in one instance, param -> constant.
* Lots of whitespace fixes, most just deleting leading tabs.
* Don't indent code blocks, they should be flush to left since any
  indentation is preserved in the output.
This commit is contained in:
John Scipione 2013-01-30 19:18:30 -05:00
parent a3c5efd2e9
commit ce5b408f1f
2 changed files with 92 additions and 89 deletions
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9
docs/user/app/Application.dox
View File

@ -387,10 +387,10 @@ main()
/*!
\fn BWindow* BApplication::WindowAt(int32 index) const
\brief Returns the BWindow object at the specified index in the
\brief Returns the BWindow object at the specified \a index in the
application's window list.
If index is out of range, this function returns \c NULL.
If \a index is out of range, this function returns \c NULL.
\warning Locking the BApplication object doesn't lock the window list.
@ -520,7 +520,8 @@ main()
If the \a rate is set to 0 then the \c B_PULSE messages are not sent.
The pulse rate can be no faster than once per 100,000 microseconds or so.
\param rate The rate \a B_PULSE messages are sent to the application.
\param rate The rate at which \c B_PULSE messages are sent to the
application.
*/

172
docs/user/app/Handler.dox
View File

@ -26,7 +26,7 @@
/*!
\def B_OBSERVE_ORIGINAL_WHAT
\brief Constant for a message data field in observer messages.
If you have called one of the flavors of BHandler::StartWachting(), and
you receive a notification, sometimes there can be send a BMessage to go
with that notification. The message you receive is a copy of that message,
@ -52,17 +52,17 @@
\class BHandler
\ingroup app
\brief Handles messages that are passed on by a BLooper.
The BHandler class implements two important pieces of functionality. It
provides the foundations for <b>handling messages</b>, and it serves as a
<b>state machine</b> that sends out notifications of the state changes.
The most common use of this class is to <b>handle messages</b>. Handlers
can be tied to loopers, which are the objects that send and receive
messages. As soon as a message is received, the looper passes through its
list of associated handlers and tries them in a certain order until the
message is handled, or the options are exhausted.
You should know that a looper is a subclass of a handler, and as such,
loopers can be self-contained and do not need additional handlers. In many
cases, this construction will suffice. You will simply subclass the looper,
@ -74,18 +74,18 @@
messages such as clicks are received, the window loops the handlers until
there is a handler that is at the screen position the click was in. It is
not unlikely that you will some day want to use this functionality of the
API.
API.
If your handler is limited to a certain type of messages, you can set a
filter that the looper will apply to your message before passing it on to
your overridden MessageReceived() method. The BMessageFilter class provides
the framework for the flexible filtering options, and using AddFilter() you
can apply filters to this handler. Note that a filter object should only be
applied to one handler. They cannot be shared.
For more information on the handling chain, have a look at the
documentation of the BLooper class.
Using BHandler as a <b>state machine</b> is a second area of functionality.
Since handlers process messages, and perform actions associated with those,
they are the center of keeping track on the current state of things within
@ -93,7 +93,7 @@
parts of your application, you could perform this manually by sending
messages to the interested components, or you can use the more flexible
approach with observers.
Observers watch a certain state. A handler can track one or more different
states. Each state is represented by a four byte constant - just like the
\c what property of a message. Using the StartWatching() methods, you can
@ -105,7 +105,7 @@
that you want to be send to the observers. This data is in the form of the
very flexible BMessage, as such you are almost free to pass anything you
want.
Whenever SendNotices() is called, all interested observers will receive a
message of the \a B_OBSERVER_NOTICE_CHANGE type. Please note that the
constant that is associated with the state itself is not transmitted. If
@ -121,7 +121,7 @@
/*!
\fn BHandler::BHandler(const char* name = NULL)
\brief Construct a new handler with a \a name.
The newly constructed handler is not associated with a looper until you
explicitly request this to happen. To associate this handler with a looper,
use BLooper::AddHandler().
@ -131,11 +131,11 @@
/*!
\fn BHandler::~BHandler()
\brief Free the filters of this handler, as well as the list of observers.
This method does not remove the handler from the looper to which this
handler is associated. You should do this yourself, using
BLooper::RemoveHandler().
\warning This constructor does no type check whatsoever. Since you can pass
any BMessage, you should - if you are not sure about the exact type -
use the Instantiate() method, which does check the type.
@ -145,7 +145,7 @@
/*!
\fn BArchivable *BHandler::Instantiate(BMessage *data)
\brief Static method to instantiate a handler from an archived message.
\return A pointer to the instantiated handler, or \c NULL if the \a data
is not a valid archived BHandler object.
\see BHandler(BMessage* data)
@ -156,18 +156,19 @@
/*!
\name Archiving
BHandler inherits the BArchivable class, and as such implements support for
archiving and unarchiving handlers.
*/
//! @{
/*!
\fn BHandler::BHandler(BMessage* data)
\brief Construct a handler from an archived message.
This \a data has to be created using the BHandler::Archive() method.
Note that only the name is stored. The filters, the associated looper and
the observers are not stored, and should be manually added when you are
@ -178,10 +179,10 @@
/*!
\fn status_t BHandler::Archive(BMessage *data, bool deep) const
\brief Archive a handler to a message
Currently, only the name is archived. The filters, the associated looper
and the observers are not stored.
\param data The message to archive the object in.
\param deep This parameter is ignored, as BHandler does not have children.
\retval B_OK Archiving succeeded.
@ -279,19 +280,19 @@ ShowImageApp::MessageReceived(BMessage *message)
/*!
\fn void BHandler::SetNextHandler(BHandler *handler)
\brief Set the next handler in the chain that the message is passed on to
if this handler cannot process it.
if this \a handler cannot process it.
This method has three requirements:
-# This handler should belong to a looper.
-# This \a handler should belong to a looper.
-# The looper needs to be locked. See LockLooper().
-# The \a handler that you pass must be associated with the same looper.
Failure to meet any of these requirements will result in your application
crashing.
By default, the handlers are chained in order that they were associated to
a looper with BLooper::AddHander().
\see NextHandler()
*/
@ -316,19 +317,19 @@ ShowImageApp::MessageReceived(BMessage *message)
//! @{
/*!
\fn void BHandler::AddFilter(BMessageFilter *filter)
\brief Add a filter as a prerequisite to this handler.
If the handler is associated with a looper, this looper needs to be locked
in order for this operation to succeed.
Note that the filter is not copied, rather a pointer to the filter is
stored. As such, you need to make sure that the filter object exists as
long as it is added to this handler.
\see RemoveFilter(), SetFilterList()
*/
@ -336,16 +337,16 @@ ShowImageApp::MessageReceived(BMessage *message)
/*!
\fn bool BHandler::RemoveFilter(BMessageFilter *filter)
\brief Remove a filter from the filter list.
If the handler is associated with a looper, this looper needs to be locked
in order for this operation to succeed.
Note that the filter is not deleted, merely removed from the list. You need
to take care of the memory yourself.
\retval true The filter was in the filter list and is removed.
\retval false The filter was not found in the filter list.
\see AddFilter(), FilterList()
*/
@ -356,7 +357,7 @@ ShowImageApp::MessageReceived(BMessage *message)
If the handler is associated with a looper, this looper needs to be locked
in order for this operation to succeed.
The internal list will be replaced with the new list of \a filters. All the
existing filters will be \b deleted.
@ -367,11 +368,11 @@ ShowImageApp::MessageReceived(BMessage *message)
/*!
\fn BList *BHandler::FilterList()
\brief Return a pointer to the list of filters.
\return A pointer to the list of filters. Do not manipulate the list of
filters directly, but use the methods provided by this class, in order
to maintain internal consistency.
\see AddFilter(), RemoveFilter(), SetFilterList().
*/
@ -384,22 +385,22 @@ ShowImageApp::MessageReceived(BMessage *message)
/*!
\name Locking
This class provides some utility functions to look the looper associated
with this handler.
*/
//! @{
/*!
\fn bool BHandler::LockLooper()
\brief Lock the looper associated with this handler.
\retval true The looper is locked.
\retval false There was an error acquiring the lock.
\see LockLooperWithTimeout(), UnlockLooper()
*/
@ -407,16 +408,16 @@ ShowImageApp::MessageReceived(BMessage *message)
/*!
\fn status_t BHandler::LockLooperWithTimeout(bigtime_t timeout)
\brief Lock the looper associated with this handler, with a time out value.
\param timeout The time to wait for acquiring the lock in microseconds. You
may also use B_INFINITE_TIMEOUT, in which this method will wait as long
as it takes to acquire the lock.
\retval B_OK Locking succeeded.
\retval B_BAD_VALUE This handler is not associated with a looper (anymore).
\retval B_TIMED_OUT The time specified in \a timeout has passed without
locking the looper.
\see LockLooper(), UnlockLooper()
*/
@ -463,16 +464,16 @@ ShowImageApp::MessageReceived(BMessage *message)
/*!
\name Observing
Handlers can function as state machines, which emit messages to observers
when the state changes. Use the following methods to subscribe to these
notifications.
Note that there is a semantic difference between the two StartWatching()
methods. The overloaded method that accepts a BHandler, expects as
argument an \a observer that watches <em>this handler</em>. The method that
argument an \a observer that watches this handler. The method that
accepts a BMessenger, expects a \a target that emits the state changes
<em>to this handler</em>.
to this handler.
*/
@ -483,25 +484,26 @@ ShowImageApp::MessageReceived(BMessage *message)
\fn status_t BHandler::StartWatching(BMessenger target, uint32 what)
\brief Subscribe this handler to watch a specific state change of a
\a target.
Use this method to subscribe messengers to watch state changes in <em>this
handler</em>. This means that also observers from other teams can be
Use this method to subscribe messengers to watch state changes in this
handler, this also means that observers from other teams can be
subscribed.
\code
// Handler B watches Handler A
BHandler A, B;
BMessenger messengerA(&A)
B.StartWatching(messengerA, kNetworkConnection);
// Handler B watches Handler A
BHandler A, B;
BMessenger messengerA(&A)
B.StartWatching(messengerA, kNetworkConnection);
\endcode
\param target The messenger from which the notifications would be
received.
\param what The state that needs to be watched.
\return During the call of this method, a notification will be transmitted
using the \a target. If this works, then this method will return
\c B_OK.
\see StartWatchingAll(BMessenger), StopWatching(BMessenger, uint32)
*/
@ -509,10 +511,10 @@ ShowImageApp::MessageReceived(BMessage *message)
/*!
\fn status_t BHandler::StartWatchingAll(BMessenger target)
\brief Subscribe this handler to watch a \a target for all events.
This method performs the same task as StartWatching(BMessenger, uint32),
but it will subscribe to all the state changes the \a target knows.
\see StartWatching(BMessenger, uint32), StopWatchingAll(BMessenger)
*/
@ -520,10 +522,10 @@ ShowImageApp::MessageReceived(BMessage *message)
/*!
\fn status_t BHandler::StopWatching(BMessenger target, uint32 what)
\brief Unsubscribe this handler from watching a specific state.
This method will unsubscribe this handler from watching a specific event
in a \a target.
\see StartWatching(BMessenger, uint32)
*/
@ -531,9 +533,9 @@ ShowImageApp::MessageReceived(BMessage *message)
/*!
\fn status_t BHandler::StopWatchingAll(BMessenger target)
\brief Unsubscribe this handler from watching all states.
This method will unsubscribe the \a target from watching all state changes.
\see StartWatchingAll(BMessenger)
*/
@ -541,39 +543,39 @@ ShowImageApp::MessageReceived(BMessage *message)
/*!
\fn status_t BHandler::StartWatching(BHandler* observer, uint32 what)
\brief Subscribe an \a observer for a specific state change of this handler.
Use this method to subscribe observers to watch this handler. State changes
of this handler that match the \a what argment, will be sent.
of this handler that match the \a what argument, will be sent.
\code
// Handler B wants to observe Handler A
BHandler A, B;
A.StartWatching(&B, kNetworkConnection);
// Handler B wants to observe Handler A
BHandler A, B;
A.StartWatching(&B, kNetworkConnection);
\endcode
Since pointers to handlers can only
exist in the local namespace, have a look at
StartWatching(BMessenger, uint32) for inter-team watching.
\param observer The observer for this handler.
\param what The state that needs to be watched.
\return During the call of this method, a notification will be transmitted
using the \a observer. If this works, then this method will return
\c B_OK.
\see StartWatchingAll(BHandler*), StopWatching(BHandler*, uint32)
*/
/*!
\fn status_t BHandler::StartWatchingAll(BHandler* observer)
\brief Subscribe an \a observer for a all state changes.
\brief Subscribe an \a observer for a all state changes.
This method performs the same task as StartWatching(BHandler, uint32),
but it will subscribe the \a observer to all the state changes this handler
tracks.
\see StartWatching(BHandler*, uint32), StopWatchingAll(BHandler*)
*/
@ -591,9 +593,9 @@ ShowImageApp::MessageReceived(BMessage *message)
/*!
\fn status_t BHandler::StopWatchingAll(BHandler* handler)
\brief Unsubscribe an observer from watching all states.
This method will unsubscribe the \a handler from watching all state changes.
\see StartWatchingAll(BHandler*)
*/
@ -606,6 +608,7 @@ ShowImageApp::MessageReceived(BMessage *message)
/*!
\name Emitting State Changes
If your handler functions as a state machine, and it has observers (which
subscribed using the StartWatching() method), you can emit these state
changes.
@ -613,12 +616,12 @@ ShowImageApp::MessageReceived(BMessage *message)
//! @{
/*!
\fn void BHandler::SendNotices(uint32 what, const BMessage *msg)
\brief Emit a state change to the observers.
The actual state (specified by \a what) will not be transmitted. This is
merely for internal bookkeeping. It is not entirely unimaginable that you
still want to inform the observers of what actually took place. You can
@ -626,13 +629,13 @@ ShowImageApp::MessageReceived(BMessage *message)
message will be copied and slightly altered: the \c what member of the
message will be \c B_OBSERVER_NOTICE_CHANGE, and the \c what constant you
specified will be stored in the #B_OBSERVE_ORIGINAL_WHAT label.
\param what The identifier of the state.
\param msg Any data associated with the state change. You retain ownership
of this data, so make sure you dispose it when you are done.
*/
/*!
\fn bool BHandler::IsWatched() const
\brief Check if there are any observers watching this handler.
@ -640,4 +643,3 @@ ShowImageApp::MessageReceived(BMessage *message)
//! @}