[lttv.git] / tags / LinuxTraceToolkitViewer-0.10.0-pre-115102007 / doc / developer / developer_guide / html / x81.html

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>3.4. How to request background computation</A
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>&#13;You will also notice the presence of a request_background_data() called in the
constructor. This function, in eventhooks.c, does verify for the presence of the
state information that could be precomputed by the main window background
computation. If it has not been precomputed, we ask for a computation and show
partial data. We also register a hook that will be called (notified) by the main
window when the requested data will become ready, so the viewer can update
itself with the new data. If no partial information would have made sense in a
particular viewer, one could choose to shown a "waiting for computation" message
while waiting for the notification. See lttvwindow/lttvwindowtraces.h for the API
of the background requests.
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76	NAME="AEN81"
77	>3.4. How to request background computation</A
78	></H1
79	><P
80	> You will also notice the presence of a request_background_data() called in the
81	constructor. This function, in eventhooks.c, does verify for the presence of the
82	state information that could be precomputed by the main window background
83	computation. If it has not been precomputed, we ask for a computation and show
84	partial data. We also register a hook that will be called (notified) by the main
85	window when the requested data will become ready, so the viewer can update
86	itself with the new data. If no partial information would have made sense in a
87	particular viewer, one could choose to shown a "waiting for computation" message
88	while waiting for the notification. See lttvwindow/lttvwindowtraces.h for the API
89	of the background requests.
90	</P
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136	>The dynamic part of a module : the viewer</TD
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