QProgressBar Class
QProgressBar 提供一个水平或垂直进度条. 更多...
| 头文件: | #include <QProgressBar> |
| qmake: | QT += widgets |
| 基类: | QWidget |
公有类型
| enum | Direction { TopToBottom, BottomToTop } |
属性
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公有函数
| QProgressBar(QWidget *parent = Q_NULLPTR) | |
| ~QProgressBar() | |
| Qt::Alignment | alignment() const |
| QString | format() const |
| bool | invertedAppearance() const |
| bool | isTextVisible() const |
| int | maximum() const |
| int | minimum() const |
| Qt::Orientation | orientation() const |
| void | resetFormat() |
| void | setAlignment(Qt::Alignment alignment) |
| void | setFormat(const QString &format) |
| void | setInvertedAppearance(bool invert) |
| void | setTextDirection(QProgressBar::Direction textDirection) |
| void | setTextVisible(bool visible) |
| virtual QString | text() const |
| QProgressBar::Direction | textDirection() const |
| int | value() const |
重新实现的公有函数
| virtual QSize | minimumSizeHint() const |
| virtual QSize | sizeHint() const |
- 214 个公有函数继承自 QWidget
- 32 个公有函数继承自 QObject
- 14 个公有函数继承自 QPaintDevice
公有槽函数
| void | reset() |
| void | setMaximum(int maximum) |
| void | setMinimum(int minimum) |
| void | setOrientation(Qt::Orientation) |
| void | setRange(int minimum, int maximum) |
| void | setValue(int value) |
信号
| void | valueChanged(int value) |
受保护的函数
| void | initStyleOption(QStyleOptionProgressBar *option) const |
重新实现的受保护函数
| virtual bool | event(QEvent *e) |
| virtual void | paintEvent(QPaintEvent *) |
- 35 个受保护的函数继承自 QWidget
- 9 个受保护的函数继承自 QObject
- 1 个受保护的函数继承自 QPaintDevice
其他继承的成员
- 1 个公有变量继承自 QObject
- 5 个静态公有成员继承自 QWidget
- 10 个静态公有成员继承自 QObject
- 1 个受保护的槽函数继承自 QWidget
- 2 个受保护的变量继承自 QObject
- 1 protected type inherited from QPaintDevice
详细描述
QProgressBar 提供一个水平或垂直进度条.
进度条可以向用户显示操作进度, 表示应用程序仍在运行.
进度条使用 步数 概念. 你可以先设置最小和最大步数, 然后再设置当前步数时, 进度条显示已完成步数的百分比. 百分比的计算方式是 (value() - minimum()) / (maximum() - minimum()).
调用 setMinimum() 和 setMaximum设置最小和最大步数. 调用 setValue()设置当前步数. 调用 reset() 重置当前步数为最小步数.
如果最小和最大步数设置为 0, 进度条显示忙碌指示器. 例如, 使用 QNetworkAccessManager 下载大小未知的资源时, 可以显示忙碌指示器.
 | A progress bar shown in the Macintosh widget style. |
 | A progress bar shown in the Windows Vista widget style. |
 | A progress bar shown in the Fusion widget style. |
参见 QProgressDialog 和 GUI Design Handbook: Progress Indicator.
成员类型
enum QProgressBar::Direction
Specifies the reading direction of the text for vertical progress bars.
| Constant | Value | Description |
|---|---|---|
QProgressBar::TopToBottom | 0 | The text is rotated 90 degrees clockwise. |
QProgressBar::BottomToTop | 1 | The text is rotated 90 degrees counter-clockwise. |
Note that whether or not the text is drawn is dependent on the style. Currently CleanLooks and Plastique draw the text. Mac, Windows and WindowsXP style do not.
This enum was introduced or modified in Qt 4.1.
参见 textDirection.
属性
alignment : Qt::Alignment
This property holds the alignment of the progress bar
访问函数:
| Qt::Alignment | alignment() const |
| void | setAlignment(Qt::Alignment alignment) |
format : QString
This property holds the string used to generate the current text
%p - is replaced by the percentage completed. %v - is replaced by the current value. %m - is replaced by the total number of steps.
The default value is "%p%".
This property was introduced in Qt 4.2.
访问函数:
| QString | format() const |
| void | setFormat(const QString &format) |
| void | resetFormat() |
参见 text().
invertedAppearance : bool
This property holds whether or not a progress bar shows its progress inverted
If this property is true, the progress bar grows in the other direction (e.g. from right to left). By default, the progress bar is not inverted.
This property was introduced in Qt 4.1.
访问函数:
| bool | invertedAppearance() const |
| void | setInvertedAppearance(bool invert) |
参见 orientation and layoutDirection.
maximum : int
This property holds the progress bar's maximum value
When setting this property, the minimum is adjusted if necessary to ensure that the range remains valid. If the current value falls outside the new range, the progress bar is reset with reset().
访问函数:
| int | maximum() const |
| void | setMaximum(int maximum) |
minimum : int
This property holds the progress bar's minimum value
When setting this property, the maximum is adjusted if necessary to ensure that the range remains valid. If the current value falls outside the new range, the progress bar is reset with reset().
访问函数:
| int | minimum() const |
| void | setMinimum(int minimum) |
orientation : Qt::Orientation
This property holds the orientation of the progress bar
The orientation must be Qt::Horizontal (the default) or Qt::Vertical.
This property was introduced in Qt 4.1.
访问函数:
| Qt::Orientation | orientation() const |
| void | setOrientation(Qt::Orientation) |
参见 invertedAppearance and textDirection.
text : const QString
This property holds the descriptive text shown with the progress bar
The text returned is the same as the text displayed in the center (or in some styles, to the left) of the progress bar.
The progress shown in the text may be smaller than the minimum value, indicating that the progress bar is in the "reset" state before any progress is set.
In the default implementation, the text either contains a percentage value that indicates the progress so far, or it is blank because the progress bar is in the reset state.
访问函数:
| virtual QString | text() const |
textDirection : Direction
This property holds the reading direction of the text for vertical progress bars
This property has no impact on horizontal progress bars. By default, the reading direction is QProgressBar::TopToBottom.
This property was introduced in Qt 4.1.
访问函数:
| QProgressBar::Direction | textDirection() const |
| void | setTextDirection(QProgressBar::Direction textDirection) |
参见 orientation and textVisible.
textVisible : bool
This property holds whether the current completed percentage should be displayed
This property may be ignored by the style (e.g., QMacStyle never draws the text).
访问函数:
| bool | isTextVisible() const |
| void | setTextVisible(bool visible) |
参见 textDirection.
value : int
This property holds the progress bar's current value
Attempting to change the current value to one outside the minimum-maximum range has no effect on the current value.
访问函数:
| int | value() const |
| void | setValue(int value) |
Notifier signal:
| void | valueChanged(int value) |
成员函数
QProgressBar::QProgressBar(QWidget *parent = Q_NULLPTR)
Constructs a progress bar with the given parent.
By default, the minimum step value is set to 0, and the maximum to 100.
参见 setRange().
QProgressBar::~QProgressBar()
Destructor.
[virtual protected] bool QProgressBar::event(QEvent *e)
重新实现 QObject::event().
[protected] void QProgressBar::initStyleOption(QStyleOptionProgressBar *option) const
Initialize option with the values from this QProgressBar. This method is useful for subclasses when they need a QStyleOptionProgressBar, but don't want to fill in all the information themselves.
参见 QStyleOption::initFrom().
[virtual] QSize QProgressBar::minimumSizeHint() const
重新实现 QWidget::minimumSizeHint().
[virtual protected] void QProgressBar::paintEvent(QPaintEvent *)
重新实现 QWidget::paintEvent().
[slot] void QProgressBar::reset()
Reset the progress bar. The progress bar "rewinds" and shows no progress.
[slot] void QProgressBar::setRange(int minimum, int maximum)
Sets the progress bar's minimum and maximum values to minimum and maximum respectively.
If maximum is smaller than minimum, minimum becomes the only legal value.
If the current value falls outside the new range, the progress bar is reset with reset().
The QProgressBar can be set to undetermined state by using setRange(0, 0).
[virtual] QSize QProgressBar::sizeHint() const
重新实现 QWidget::sizeHint().
[signal] void QProgressBar::valueChanged(int value)
This signal is emitted when the value shown in the progress bar changes. value is the new value shown by the progress bar.
Note: Notifier signal for property value.