Qt Slot Derived Class

Register here: http://gg.gg/x796d
The QSensor class represents a single hardware sensor. More..
*Qt Slot Derived Class C
*Qt No Such Slot In Derived Class
*Qt Slot Derived Class Example
*Qt Slot Derived Classic
*Qt Slot Derived Classes Header:#include <QSensor> qmake: QT += sensors Since: Qt 5.1 Inherits:QObject Inherited By:
QAccelerometer, QAltimeter, QAmbientLightSensor, QAmbientTemperatureSensor, QCompass, QDistanceSensor, QGyroscope, QHolsterSensor, QHumiditySensor, QIRProximitySensor, QLidSensor, QLightSensor, QMagnetometer, QOrientationSensor, QPressureSensor, QProximitySensor, QRotationSensor, QTapSensor, and QTiltSensor
QObject is the most basic class in Qt. Most of classes in Qt inherit from this class. QObject provides some very powerful capabilities like: object name: you can set a name, as a string, to an object and search for objects by names. Parenting system (described in the following section) signals and slots (described in the next chapter) event. Make sure the QOBJECT macro is present in the definition of all QObject-derived classes. Make sure you declare your QObject-derived classes in your header files ONLY. Make sure all of your header files are listed in your.pro file in the HEADERS= list. Run qmake every time you add QOBJECT to one of your classes or modify your.pro file. Sometimes it is even desirable to have the signal private. This is the case for example in QAbstractItemModel, where otherwise, developers tend to emit signal from the derived class which is not what the API wants. There used to be a pre-processor trick that made signals private but it broke the new connection syntax. We bake cookies in your browser for a better experience. Using this site means that you consent.
This class was introduced in Qt 5.1.Public Types enum AxesOrientationMode { FixedOrientation, AutomaticOrientation, UserOrientation } enum Feature { Buffering, AlwaysOn, SkipDuplicates, GeoValues, FieldOfView, …, AxesOrientation }Properties
*active : bool
*alwaysOn : bool
*availableDataRates : const qrangelist
*axesOrientationMode : AxesOrientationMode
*bufferSize : int
*busy : const bool
*connectedToBackend : const bool
*currentOrientation : const int
*dataRate : int
*description : const QString
*efficientBufferSize : const int
*error : const int
*identifier : QByteArray
*maxBufferSize : const int
*outputRange : int
*outputRanges : const qoutputrangelist
*reading : QSensorReading* const
*skipDuplicates : bool
*type : const QByteArray
*userOrientation : intPublic FunctionsQSensor(const QByteArray &type, QObject *parent = Q_NULLPTR) virtual ~QSensor() void addFilter(QSensorFilter *filter) qrangelist availableDataRates() const QSensor::AxesOrientationMode axesOrientationMode() const int bufferSize() const bool connectToBackend() int currentOrientation() const int dataRate() const QString description() const int efficientBufferSize() const int error() const QList<QSensorFilter *> filters() const QByteArray identifier() const bool isActive() const bool isAlwaysOn() const bool isBusy() const bool isConnectedToBackend() const bool isFeatureSupported(QSensor::Feature feature) const int maxBufferSize() const int outputRange() const qoutputrangelist outputRanges() const QSensorReading *reading() const void removeFilter(QSensorFilter *filter) void setActive(bool active) void setAlwaysOn(bool alwaysOn) void setAxesOrientationMode(QSensor::AxesOrientationMode axesOrientationMode) void setBufferSize(int bufferSize) void setCurrentOrientation(int currentOrientation) void setDataRate(int rate) void setEfficientBufferSize(int efficientBufferSize) void setIdentifier(const QByteArray &identifier) void setMaxBufferSize(int maxBufferSize) void setOutputRange(int index) void setSkipDuplicates(bool skipDuplicates) void setUserOrientation(int userOrientation) bool skipDuplicates() const QByteArray type() const int userOrientation() constPublic SlotsSignals void activeChanged() void alwaysOnChanged() void availableSensorsChanged() void axesOrientationModeChanged(QSensor::AxesOrientationMode axesOrientationMode) void bufferSizeChanged(int bufferSize) void busyChanged() void currentOrientationChanged(int currentOrientation) void dataRateChanged() void efficientBufferSizeChanged(int efficientBufferSize) void maxBufferSizeChanged(int maxBufferSize) void readingChanged() void sensorError(int error) void skipDuplicatesChanged(bool skipDuplicates) void userOrientationChanged(int userOrientation)Static Public Members QByteArray defaultSensorForType(const QByteArray &type) QList<QByteArray> sensorTypes() QList<QByteArray> sensorsForType(const QByteArray &type)Related Non-Members typedef qoutputrangelist typedef qrange typedef qrangelistDetailed Description
The life cycle of a sensor is typically:
*Create a sub-class of QSensor on the stack or heap.
*Setup as required by the application.
*Start receiving values.
*Sensor data is used by the application.
*Stop receiving values.
The sensor data is delivered via QSensorReading and its sub-classes.Orientation
Some sensors react to screen orientation changes, such as QAccelerometer, QMagnetometer and QRotationSensor. These are so called orientable sensors. For orientable sensors, QSensor supports changing the reporting of the reading values based on the orientation of the screen.
For orientable sensors, the axesOrientationMode property controls how the orientation affects the reading values.
In the default mode, QSensor::FixedOrientation, the reading values remain unaffected by the orientation. In the QSensor::AutomaticOrientation mode, the reading values are automatically rotated by taking the current screen orientation into account. And finally, in the QSensor::UserOrientation mode, the reading values are rotated according to a user-specified orientation.
The functionality of this is only available if it is supported by the backend and if the sensor is orientable, which can be checked by calling QSensor::isFeatureSupported() with the QSensor::AxesOrientation flag.
The orientation values here are always of the screen orientation, not the device orientation. The screen orientation is the orientation of the GUI. For example when rotating a device by 90 degrees counter-clockwise, the screen orientation compensates for that by rotating 90 degrees clockwise, to the effect that the GUI is still facing upright after the device has been rotated. Note that applications can lock the screen orientation, for example to force portrait or landscape mode. For locked orientations, orientable sensors will not react with reading changes if the device orientation is changed, as orientable sensors react to screen orientation changes only. This makes sense, as the purpose of orientable sensors is to keep the sensor orientation in sync with the screen orientation.
The orientation values range from 0 to 270 degrees. The orientation is applied in clockwise direction, e.g. an orientation value of 90 degrees means that the screen has been rotated 90 degress to the right from its origin position, to compensate a device rotation of 90 degrees to the left.
See also QSensorReading.Member Type Documentationenum QSensor::AxesOrientationMode
Describes how reading values are affected by the screen orientation.ConstantValueDescriptionQSensor::FixedOrientation0No automatic rotation is applied to the reading values.QSensor::AutomaticOrientation1The reading values are automatically rotated based on the screen orientation.QSensor::UserOrientation2The reading values are rotated based on the angle of the userOrientation property.
This enum was introduced or modified in Qt 5.1.
See also QSensor::axesOrientationMode.enum QSensor::Feature
Lists optional features a backend might support.
The features common to all sensor types are:ConstantValueDescriptionQSensor::Buffering0The backend supports buffering of readings, controlled by the QSensor::bufferSize property.QSensor::AlwaysOn1The backend supports changing the policy on whether to suspend when idle, controlled by the QSensor::alwaysOn property.QSensor::SkipDuplicates5The backend supports skipping of same or very similar successive readings. This can be enabled by setting the QSensor::skipDuplicates property to true.
The features of QMagnetometer are:ConstantValueDescriptionQSensor::GeoValues2The backend supports returning geo values, which can be controlled with the QMagnetometer::returnGeoValues property.
The features of QLightSensor are:ConstantValueDescriptionQSensor::FieldOfView3The backend specifies its field of view, which can be read from the QLightSensor::fieldOfView property.
The features of QAccelerometer are:ConstantValueDescriptionQSensor::AccelerationMode4The backend supports switching the acceleration mode of the acceleromter with the QAccelerometer::accelerationMode property.
The features of QPressureSensor are:ConstantValueDescriptionQSensor::PressureSensorTemperature7The backend provides the pressure sensor’s die temperature
The features of all orientable sensors are:ConstantValueDescriptionQSensor::AxesOrientation6The backend supports changing the axes orientation from the default of QSensor::FixedOrientation to something else.
This enum was introduced or modified in Qt 5.0.
See also QSensor::isFeatureSupported().Property Documentationactive : bool
This property holds a value to indicate if the sensor is active.
This is true if the sensor is active (returning values). This is false otherwise.
Note that setting this value to true will not have an immediate effect. Instead, the sensor will be started once the event loop has been reached.
Access functions: bool isActive() const void setActive(bool active)
Notifier signal:alwaysOn : bool
This property holds a value to indicate if the sensor should remain running when the screen is off.
Some platforms have a policy of suspending sensors when the screen turns off. Setting this property to true will ensure the sensor continues to run.
Access functions: bool isAlwaysOn() const void setAlwaysOn(bool alwaysOn)
Notifier signal:availableDataRates : const qrangelist
This property holds the data rates that the sensor supports.
This is a list of the data rates that the sensor supports. Measured in Hertz.
Entries in the list can represent discrete rates or a continuous range of rates. A discrete rate is noted by having both values the same.
See the sensor_explorer example for an example of how to interpret and use this information.
Note that this information is not mandatory as not all sensors have a rate at which they run. In such cases, the list will be empty.
Access functions: qrangelist availableDataRates() const
See also QSensor::dataRate and qrangelist.axesOrientationMode : AxesOrientationMode
This property holds the mode that affects how the screen orientation changes reading values.
When set to FixedOrientation, which is the default mode, no automatic rotation is applied to the reading. This is the only mode available for backends that do not support the QSensor::AxesOrientation feature.
When set to AutomaticOrientation, the reading values are automatically rotated when the screen orientation changes. In effect, the screen orientation is canceled out.
As an example, assume the device is rotated by 180 degrees and therefore the screen orientation also is rotated by 180 degrees from the native orientation. Without automatic axes orientation, the reading values would now be changed: Both the X and the Y values would be negated, forcing an application developer to manually cancel out the negation in application code. Automatic axes orientation does this automatically, in this mode the X and Y values would be the same as with the default screen orientation.
This automatic rotation of the axes is handy is some usecases, for example in a bubble level application that measures how level a surface is by looking at the X axis value of an accelerometer. When the device and screen orientation change by 90 degrees, an application developer does not need to change anything, he can continue using the X axis value even though the device is rotated. Without automatic axes orientation, the application developer would need to look at the Y values instead, thereby adding code to the application that reads from a different axis depending on the screen orientation.
The UserOrientation mode is quite similar to AutomaticOrientation, only that the screen orientation is manually controlled instead of automatically determined. The angle of the userOrientation property is then used for rotating the reading values.
Since the rotation of the reading values is based on the screen orientation, Z values will never change, as the Z axis is perpendicular to the screen. As screen orientation changes in 90 degree steps, rotating the reading values is also done in steps of 90 degrees.
This property is only used for orientable sensors.
This property was introduced in Qt 5.1.
Access functions: QSensor::AxesOrientationMode axesOrientationMode() const void setAxesOrientationMode(QSensor::AxesOrientationMode axesOrientationMode)
Notifier signal: void axesOrientationModeChanged(QSensor::AxesOrientationMode axesOrientationMode)bufferSize : int
This property holds the size of the buffer. By default, the buffer size is 1, which means no buffering. If the maximum buffer size is 1, then buffering is not supported by the sensor.
Setting bufferSize greater than maxBufferSize will cause maxBufferSize to be used.
Buffering is turned on when bufferSize is greater than 1. The sensor will collect the requested number of samples and deliver them all to the application at one time. They will be delivered to the application as a burst of changed readings so it is particularly important that the application processes each reading immediately or saves the values somewhere else.
If stop() is called when buffering is on-going, the partial buffer is not delivered.
When the sensor is started with buffering option, values are collected from that moment onwards. There is no pre-existing buffer that can be utilized.
Some backends only support enabling or disabling the buffer and do not give control over the size. In this case, the maxBufferSize and efficientBufferSize properties might not be set at all, even though buffering is supported. Setting the bufferSize property to any value greater than 1 will enable buffering. After the sensor has been started, the bufferSize property will be set to the actual value by the backend.
Access functions: int bufferSize() const void setBufferSize(int bufferSize)
Notifier signal:
See also QSensor::maxBufferSize and QSensor::efficientBufferSize.busy : const bool
This property holds a value to indicate if the sensor is busy.
Some sensors may be on the system but unavailable for use. This function will return true if the sensor is busy. You will not be able to start() the sensor.
Note that this function does not return true if you are using the sensor, only if another process is using the sensor.
Access functions: bool isBusy() const
See also busyChanged().connectedToBackend : const bool
This property holds a value indicating if the sensor has connected to a backend.
A sensor that has not been connected to a backend cannot do anything useful.
Call the connectToBackend() method to force the sensor to connect to a backend immediately. This is automatically called if you call start() so you only need to do this if you need access to sensor properties (ie. to poll the sensor’s meta-data before you use it).
Access functions:currentOrientation : const int
This property holds the current orientation that is used for rotating the reading values.
This might not be the same as the screen orientation. For example, in the FixedOrientation mode, the reading values are not rotated, and therefore the property is 0.
In the UserOrientation mode, the readings are rotated based on the userOrientation property, and therefore this property is equal to the userOrientation property.
In the AutomaticOrientation mode, the readings are rotated based on the screen orientation, and therefore this property will be equal to the current screen orientation.
This property is set by the backend and only valid for orientable sensors.
This property was introduced in Qt 5.1.
Access functions: int currentOrientation() const
Poker table positions lojack. Notifier signal: void currentOrientationChanged(int currentOrientation)dataRate : int
This property holds the data rate that the sensor should be run at.
Measured in Hertz.
The data rate is the maximum frequency at which the sensor can detect changes.
Setting this property is not portable and can cause conflicts with other applications. Check with the sensor backend and platform documentation for any policy regarding multiple applications requesting a data rate.
The default value (0) means that the app does not care what the data rate is. Applications should consider using a timer-based poll of the current value or ensure that the code that processes values can run very quickly as the platform may provide updates hundreds of times each second.
This should be set before calling start() because the sensor may not notice changes to this value while it is running.
Note that there is no mechanism to determine the current data rate in use by the platform.
Access functions:
Notifier signal: void dataRateChanged()
See also QSensor::availableDataRates.description : const QString
This property holds a descriptive string for the sensor.
Access functions:efficientBufferSize : const int
The property holds the most efficient buffer size. Normally this is 1 (which means no particular size is most efficient). Some sensor drivers have a FIFO buffer which makes it more efficient to deliver the FIFO’s size worth of readings at one time.
Access functions: int efficientBufferSize() const
Notifier signal: void efficientBufferSizeChanged(int efficientBufferSize)
See also QSensor::bufferSize and QSensor::maxBufferSize.error : const int
This property holds the last error code set on the sensor.
Note that error codes are sensor-specific.
Access functions:
Notifier signal: void sensorError(int error)identifier : QByteArray
This property holds the backend identifier for the sensor.
Note that the identifier is filled out automatically when the sensor is connected to a backend. If you want to connect a specific backend, you should call setIdentifier() before connectToBackend().
Access functions: QByteArray identifier() const void setIdentifier(const QByteArray &identifier)maxBufferSize : const int
The property holds the maximum buffer size.
Note that this may be 1, in which case the sensor does not support any form of buffering. In that case, isFeatureSupported(QSensor::Buffering) will also return false.
Access functions:
Notifier signal: void maxBufferSizeChanged(int maxBufferSize)
See also QSensor::bufferSize and QSensor::efficientBufferSize.outputRange : int
This property holds the output range in use by the sensor.
Thi

https://diarynote-jp.indered.space