QSpinBox allows the user to choose a value by clicking the up/down buttons or pressing up/down on the keyboard to increase/decrease the value currently displayed. The user can also type the value in manually. The spin box supports integer values but can be extended to use different strings with
textFromValue() and .
Every time the value changes
valueChanged() and signals, the former providing a int and the latter a
QString . The signal provides the value with both
suffix() . The current value can be fetched with
value() and set with
Clicking the up/down buttons or using the keyboard accelerator’s up and down arrows will increase or decrease the current value in steps of size
singleStep() . If you want to change this behaviour you can reimplement the virtual function
stepBy() . The minimum and maximum value and the step size can be set using one of the constructors, and can be changed later with
Most spin boxes are directional, but
QSpinBox can also operate as a circular spin box, i.e. if the range is 0-99 and the current value is 99, clicking “up” will give 0 if
wrapping() is set to true. Use
setWrapping() if you want circular behavior.
The displayed value can be prepended and appended with arbitrary strings indicating, for example, currency or the unit of measurement. See
setSuffix() . The text in the spin box is retrieved with
text() (which includes any
suffix() ), or with
cleanText() (which has no
prefix() , no
suffix() and no leading or trailing whitespace).
suffix() , and
specialValueText() don’t provide enough control, you subclass
QSpinBox and reimplement and
textFromValue() . For example, here’s the code for a custom spin box that allows the user to enter icon sizes (e.g., “32 x 32”):
def valueFromText(self, text): regExp = QRegExp(tr("(\\d+)(\\s*[xx]\\s*\\d+)?")) if regExp.exactMatch(text): return regExp.cap(1).toInt() else: return 0 def textFromValue(self, value): return self.tr("%1 x %1").arg(value)
See the Icons example for the full source code.
Constructs a spin box with 0 as minimum value and 99 as maximum value, a step value of 1. The value is initially set to 0. It is parented to
- Return type
base – int
min – int
max – int
Convenience function to set the
maximum values with a single function call.
is equivalent to:
Sets the step type for the spin box to
stepType, which is single step or adaptive decimal step.
Adaptive decimal step means that the step size will continuously be adjusted to one power of ten below the current
value . So when the value is 1100, the step is set to 100, so stepping up once increases it to 1200. For 1200 stepping up takes it to 1300. For negative values, stepping down from -1100 goes to -1200.
Step direction is taken into account to handle edges cases, so that stepping down from 100 takes the value to 99 instead of 90. Thus a step up followed by a step down – or vice versa – always lands on the starting value; 99 -> 100 -> 99.
arg__1 – str
val – int
- Return type
This virtual function is used by the spin box whenever it needs to display the given
value. The default implementation returns a string containing
value printed in the standard way using
locale() .toString(), but with the thousand separator removed unless
setGroupSeparatorShown() is set. Reimplementations may return anything. (See the example in the detailed description.)
If you reimplement this, you may also need to reimplement and
arg__1 – int
text – str
- Return type
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