Exploring the Value Space with vsexplorer
The vsexplorer tool is provided for diagnosing issues with the Value Space. Many services write values into the value space so that they are accessible to Qt Extended libraries, applications, themes, etc.
The vsexplorer tool can be used to inspect the contents of the value space on a device, to make temporary modifications, and to watch for changes in specific value space items.
When run from the command-line normally, it launches an interpreter environment that can accept commands. The commands are very similar to using a Unix-style command-prompt, as shown in the current example:
$ vsexplorer
/ > ls
Hardware/
Accessories/
Documents/
Network/
UI/
Telephony/
MediaServer/
System/
AudioManager/
Communications/
/ > cd Telephony
/Telephony > ls
Status/
/Telephony > cd Status
/Telephony/Status > ls
CallDivert/ 'false' (bool)
Roaming/ 'false' (bool)
SimToolkitAvailable/ 'false' (bool)
RegistrationState/ 'Home' (QString)
OperatorCountry/ '' (QString)
SMSMemoryFull/ '0' (int)
CellModemAvailable/ 'true' (bool)
ModemStatus/ 'Ready' (QString)
PlaneModeAvailable/ 'Yes' (QString)
VoIP/
CellLocation/ '' (QString)
NetworkRegistered/ 'true' (bool)
OperatorName/ 'Qt Extended Comm' (QString)
/Telephony > exit
$ _
The tool prints the current value space directory, starting at the root. The user can use cd to change into a new directory, and ls to list the directory's contents. If the directory contains item values, their values will be listed. You can always return to the root of the value space by typing cd /. The exit command exits from the vsexplorer interpreter.
Commands
The following commands are available in vsexplorer:
| Command | Description |
|---|
| help, ? | Print help on the available commands. |
| exit, quit | Exit from vsexplorer. |
| cd name | Change into the value space directory called name. |
| ls | List the contents of the current value space directory. |
| ls name | List the contents of the value space directory called name. |
| set name value | Set the value space item called name to value. This can be used from vsexplorer to make temporary changes to the value space for testing other applications. The changes will be removed when vsexplorer exits. |
| clear name | Clear the value space item called name. This will remove any previous values that were set on name using the set command. This cannot be used to clear values that were set by other applications. |
| subscribe, sub | Subscribe to change notifications on the current directory. Whenever a service in Qt Extended makes a change to this directory or one of its subdirectories, a message Changed: name will be printed for the directory that was subscribed to. The user can then use ls to inspect the new values. |
| unsubscribe, unsub | Unsubscribe from change notifications on the current directory. |
| subscriptions | Print the current list of change notification subscriptions. |
| write name value | Send a request to the application that controls the value space item name to change it to value. This does not actually set the value, but asks the owning application to set it. The application is free to ignore the request. This feature is not used very often in Qt Extended. The set command is more likely to be useful. |
| remove name | Send a request to the application that controls the value space item name to remove it from the value space. This does not actually remove the value, but asks the owning application to remove it. The application is free to ignore the request. This feature is not used very often in Qt Extended. The clear command is more likely to be useful. |
| watch name | Watch for requests to change the value space item name. Requests that come from write and remove commands will activate such a watch. This feature is not used very often in Qt Extended. The subscribe command is more likely to be useful. |
| unwatch name | Remove a watch for requests to change the value space item name. This feature is not used very often in Qt Extended. The unsubscribe command is more likely to be useful. |
| watchers | Print the current list of watchers that were installed with the watch command. |
| suppress | Toggle the suppression state for messages printed by watchers that were installed with the watch command. The watchers will remain installed, but the normal messages that they print will be suppressed until another suppress command is seen. |
Dump Mode
The vsexplorer tool can be run in a second mode where it dumps the entire contents of the value space instead of entering the interpreter. This dump mode is activated by typing vsexplorer -d. The following is an example of dumping all values under /Telephony/Status and writing it to the file status.out:
$ vsexplorer -d | grep /Telephony/Status >status.out
