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The QAbstractSlider class provides an integer value within a range. More...
Inherits QWidget.
Inherited by QDial, QScrollBar and QSlider.
The QAbstractSlider class provides an integer value within a range.
The class is designed as a common super class for widgets like QScrollBar, QSlider and QDial.
Here are the main properties of the class:
Unity (1) may be viewed as a third step size. setValue() lets you set the current value to any integer in the allowed range, not just minimum() + n * singleStep() for integer values of n. Some widgets may allow the user to set any value at all; others may just provide multiples of singleStep() or pageStep().
QAbstractSlider emits a comprehensive set of signals:
| Signal | Emitted when |
|---|---|
| valueChanged() | the value has changed. The tracking determines whether this signal is emitted during user interaction. |
| sliderPressed() | the user starts to drag the slider. |
| sliderMoved() | the user drags the slider. |
| sliderReleased() | the user releases the slider. |
| actionTriggered() | a slider action was triggerd. |
| rangeChanged() | a the range has changed. |
QAbstractSlider provides a virtual sliderChange() function that is well suited for updating the on-screen representation of sliders. By calling triggerAction(), subclasses trigger slider actions. Two helper functions QStyle.sliderPositionFromValue() and QStyle.sliderValueFromPosition() help subclasses and styles to map screen coordinates to logical range values.
| Constant | Value |
|---|---|
| QAbstractSlider.SliderNoAction | 0 |
| QAbstractSlider.SliderSingleStepAdd | 1 |
| QAbstractSlider.SliderSingleStepSub | 2 |
| QAbstractSlider.SliderPageStepAdd | 3 |
| QAbstractSlider.SliderPageStepSub | 4 |
| QAbstractSlider.SliderToMinimum | 5 |
| QAbstractSlider.SliderToMaximum | 6 |
| QAbstractSlider.SliderMove | 7 |
| Constant | Value |
|---|---|
| QAbstractSlider.SliderRangeChange | 0 |
| QAbstractSlider.SliderOrientationChange | 1 |
| QAbstractSlider.SliderStepsChange | 2 |
| QAbstractSlider.SliderValueChange | 3 |
The parent argument, if not None, causes self to be owned by Qt instead of PyQt.
Constructs an abstract slider.
The parent argument is sent to the QWidget constructor.
The minimum defaults to 0, the maximum to 99, with a singleStep size of 1 and a pageStep size of 10, and an initial value of 0.
Reimplemented from QWidget.changeEvent().
Reimplemented from QObject.event().
Reimplemented from QWidget.keyPressEvent().
Returns the current repeat action.
See also setRepeatAction().
This method is also a Qt slot with the C++ signature void setOrientation( ::Qt::Orientation).
Sets the slider's minimum to min and its maximum to max.
If max is smaller than min, min becomes the only legal value.
Sets action action to be triggered repetitively in intervals of repeatTime, after an initial delay of thresholdTime.
See also triggerAction() and repeatAction().
This method is also a Qt slot with the C++ signature void setValue(int).
Reimplement this virtual function to track slider changes such as SliderRangeChange, SliderOrientationChange, SliderStepsChange, or SliderValueChange. The default implementation only updates the display and ignores the change parameter.
Reimplemented from QObject.timerEvent().
Triggers a slider action. Possible actions are SliderSingleStepAdd, SliderSingleStepSub, SliderPageStepAdd, SliderPageStepSub, SliderToMinimum, SliderToMaximum, and SliderMove.
See also actionTriggered().
Reimplemented from QWidget.wheelEvent().
This is the default overload of this signal.
This signal is emitted when the slider action action is triggered. Actions are SliderSingleStepAdd, SliderSingleStepSub, SliderPageStepAdd, SliderPageStepSub, SliderToMinimum, SliderToMaximum, and SliderMove.
When the signal is emitted, the sliderPosition has been adjusted according to the action, but the value has not yet been propagated (meaning the valueChanged() signal was not yet emitted), and the visual display has not been updated. In slots connected to this signal you can thus safely adjust any action by calling setSliderPosition() yourself, based on both the action and the slider's value.
See also triggerAction().
This is the default overload of this signal.
This signal is emitted when the slider range has changed, with min being the new minimum, and max being the new maximum.
This is the default overload of this signal.
This signal is emitted when sliderDown is true and the slider moves. This usually happens when the user is dragging the slider. The value is the new slider position.
This signal is emitted even when tracking is turned off.
See also setTracking(), valueChanged(), isSliderDown(), sliderPressed(), and sliderReleased().
This is the default overload of this signal.
This signal is emitted when the user presses the slider with the mouse, or programmatically when setSliderDown(true) is called.
See also sliderReleased(), sliderMoved(), and isSliderDown().
This is the default overload of this signal.
This signal is emitted when the user releases the slider with the mouse, or programmatically when setSliderDown(false) is called.
See also sliderPressed(), sliderMoved(), and sliderDown.
This is the default overload of this signal.
This signal is emitted when the slider value has changed, with the new slider value as argument.
| PyQt 4.12.1 for X11 | Copyright © Riverbank Computing Ltd and The Qt Company 2015 | Qt 4.8.7 |