The QTapReading class represents one reading from the tap sensor. 更多...
头: | #include <QTapReading> |
qmake: | QT += sensors |
Since: | Qt 5.1 |
继承: | QSensorReading |
enum | TapDirection { Undefined, X, Y, Z, ..., Z_Both } |
bool | isDoubleTap () const |
void | setDoubleTap (bool doubleTap ) |
void | setTapDirection (TapDirection tapDirection ) |
TapDirection | tapDirection () const |
The QTapReading class represents one reading from the tap sensor.
The tap sensor registers tap events along the 3 axes that originate from the phone. The axes are arranged as follows.
By default it returns only double tap events. The QTapSensor::returnDoubleTapEvents property must be set to false to return individual tap events.
The tap direction is indicated using flags. Applications should check for the presence of a particular flag as multiple flags may be set at once.
The X, Y and Z flags allow an app to check for taps along an axis without caring about the direction.
if (reading->tapDirection()&QTapReading::X) { ... }
The *_Pos and *_Neg flags allow checking for taps in a specific direction. Note that some devices cannot determine the direction of a tap and will set both the _Pos and _Neg flag for the detected axis. Previous versions of the API did not allow this. Applications that check for the _Pos and _Neg flags as values should be updated so they can work with all devices.
例如,若有代码像
if (reading->tapDirection() == QTapReading::X_Pos) { ... }
可以把它重写成
if (reading->tapDirection()&QTapReading::X_Pos) { ... }
常量 | 值 | 描述 |
---|---|---|
QTapReading::Undefined
|
0
|
This value means that the direction is unknown. |
QTapReading::X
|
0x0001
|
This flag is set if the tap was along the X axis. |
QTapReading::Y
|
0x0002
|
This flag is set if the tap was along the Y axis. |
QTapReading::Z
|
0x0004
|
This flag is set if the tap was along the Z axis. |
QTapReading::X_Pos
|
0x0011
|
This flag is set if the tap was towards the positive X direction. |
QTapReading::Y_Pos
|
0x0022
|
This flag is set if the tap was towards the positive Y direction. |
QTapReading::Z_Pos
|
0x0044
|
This flag is set if the tap was towards the positive Z direction. |
QTapReading::X_Neg
|
0x0101
|
This flag is set if the tap was towards the negative X direction. |
QTapReading::Y_Neg
|
0x0202
|
This flag is set if the tap was towards the negative Y direction. |
QTapReading::Z_Neg
|
0x0404
|
This flag is set if the tap was towards the negative Z direction. |
QTapReading::X_Both
|
0x0111
|
相当于
X_Pos|X_Neg
. Returned by devices that cannot detect the direction of a tap.
|
QTapReading::Y_Both
|
0x0222
|
相当于
Y_Pos|Y_Neg
. Returned by devices that cannot detect the direction of a tap.
|
QTapReading::Z_Both
|
0x0444
|
相当于
Z_Pos|Z_Neg
. Returned by devices that cannot detect the direction of a tap.
|
This property holds a value indicating if there was a single or double tap.
访问函数:
bool | isDoubleTap () const |
另请参阅 QTapReading Units .
This property holds the direction of the tap.
访问函数:
TapDirection | tapDirection () const |
另请参阅 QTapReading Units .
Sets the double tap status of the reading to doubleTap .
另请参阅 isDoubleTap ().
Sets the tap direction to tapDirection .
另请参阅 tapDirection ().