git.saurik.com Git - wxWidgets.git/blame_incremental

... / ...

Commit	Line	Data
	1	\section{\class{wxThreadHelper}}\label{wxthreadhelper}
	2
	3	The wxThreadHelper class is a mix-in class that manages a single background
	4	thread. By deriving from wxThreadHelper, a class can implement the thread
	5	code in its own \helpref{wxThreadHelper::Entry}{wxthreadhelperentry} method
	6	and easily share data and synchronization objects between the main thread
	7	and the worker thread. Doing this prevents the awkward passing of pointers
	8	that is needed when the original object in the main thread needs to
	9	synchronize with its worker thread in its own wxThread derived object.
	10
	11	For example, \helpref{wxFrame}{wxframe} may need to make some calculations
	12	in a background thread and then display the results of those calculations in
	13	the main window.
	14
	15	Ordinarily, a \helpref{wxThread}{wxthread} derived object would be created
	16	with the calculation code implemented in
	17	\helpref{wxThread::Entry}{wxthreadentry}. To access the inputs to the
	18	calculation, the frame object would often to pass a pointer to itself to the
	19	thread object. Similiarly, the frame object would hold a pointer to the
	20	thread object. Shared data and synchronization objects could be stored in
	21	either object though the object without the data would have to access the
	22	data through a pointer.
	23
	24	However, with wxThreadHelper, the frame object and the thread object are
	25	treated as the same object. Shared data and synchronization variables are
	26	stored in the single object, eliminating a layer of indirection and the
	27	associated pointers.
	28
	29	\wxheading{Derived from}
	30
	31	None.
	32
	33	\wxheading{Include files}
	34
	35	<wx/thread.h>
	36
	37	\wxheading{See also}
	38
	39	\helpref{wxThread}{wxthread}, \helpref{wxThreadHelperThread}{wxthreadhelperthread}
	40
	41	\latexignore{\rtfignore{\wxheading{Members}}}
	42
	43	\membersection{wxThreadHelper::wxThreadHelper}\label{wxthreadhelperctor}
	44
	45	\func{}{wxThreadHelper}{\void}
	46
	47	This constructor simply initializes a member variable.
	48
	49	\membersection{wxThreadHelper::m\_thread}
	50
	51	\member{wxThread *}{m\_thread}
	52
	53	the actual \helpref{wxThread}{wxthread} object.
	54
	55	\membersection{wxThread::\destruct{wxThreadHelper}}
	56
	57	\func{}{\destruct{wxThreadHelper}}{\void}
	58
	59	The destructor frees the resources associated with the thread.
	60
	61	\membersection{wxThreadHelper::Create}\label{wxthreadhelpercreate}
	62
	63	\func{wxThreadError}{Create}{\param{unsigned int }{stackSize = 0}}
	64
	65	Creates a new thread. The thread object is created in the suspended state, and you
	66	should call \helpref{GetThread()->Run()}{wxthreadhelperthreadrun} to start running
	67	it. You may optionally specify the stack size to be allocated to it (Ignored on
	68	platforms that don't support setting it explicitly, eg. Unix).
	69
	70	\wxheading{Return value}
	71
	72	One of:
	73
	74	\twocolwidtha{7cm}
	75	\begin{twocollist}\itemsep=0pt
	76	\twocolitem{{\bf wxTHREAD\_NO\_ERROR}}{There was no error.}
	77	\twocolitem{{\bf wxTHREAD\_NO\_RESOURCE}}{There were insufficient resources to create a new thread.}
	78	\twocolitem{{\bf wxTHREAD\_RUNNING}}{The thread is already running.}
	79	\end{twocollist}
	80
	81	\membersection{wxThreadHelper::Entry}\label{wxthreadhelperentry}
	82
	83	\func{virtual ExitCode}{Entry}{\void}
	84
	85	This is the entry point of the thread. This function is pure virtual and must
	86	be implemented by any derived class. The thread execution will start here.
	87
	88	The returned value is the thread exit code which is only useful for
	89	joinable threads and is the value returned by
	90	\helpref{GetThread()->Wait()}{wxthreadwait}.
	91
	92	This function is called by wxWindows itself and should never be called
	93	directly.
	94
	95	\membersection{wxThreadHelper::GetThread}\label{wxthreadhelpergetthread}
	96
	97	\func{wxThread *}{GetThread}{\void}
	98
	99	This is a public function that returns the \helpref{wxThread}{wxthread} object
	100	associated with the thread.