QLCDNumber 小部件显示带有类似 LCD 数字的数字。 更多...
头: | #include <QLCDNumber> |
CMake: |
find_package(Qt6 COMPONENTS Widgets REQUIRED)
target_link_libraries(mytarget PRIVATE Qt6::Widgets) |
qmake: | QT += widgets |
继承: | QFrame |
enum | Mode { Hex, Dec, Oct, Bin } |
enum | SegmentStyle { Outline, Filled, Flat } |
|
|
QLCDNumber (uint numDigits , QWidget * parent = nullptr) | |
QLCDNumber (QWidget * parent = nullptr) | |
virtual | ~QLCDNumber () |
bool | checkOverflow (double num ) const |
bool | checkOverflow (int num ) const |
int | digitCount () const |
int | intValue () const |
QLCDNumber::Mode | mode () const |
QLCDNumber::SegmentStyle | segmentStyle () const |
void | setDigitCount (int numDigits ) |
void | setMode (QLCDNumber::Mode) |
void | setSegmentStyle (QLCDNumber::SegmentStyle) |
bool | smallDecimalPoint () const |
double | value () const |
virtual QSize | sizeHint () const override |
void | display (double num ) |
void | display (int num ) |
void | display (const QString & s ) |
void | setBinMode () |
void | setDecMode () |
void | setHexMode () |
void | setOctMode () |
void | setSmallDecimalPoint (bool) |
void | overflow () |
virtual bool | event (QEvent * e ) override |
virtual void | paintEvent (QPaintEvent *) override |
It can display a number in just about any size. It can display decimal, hexadecimal, octal or binary numbers. It is easy to connect to data sources using the display () slot, which is overloaded to take any of five argument types.
There are also slots to change the base with setMode () and the decimal point with setSmallDecimalPoint ().
QLCDNumber emits the overflow () signal when it is asked to display something beyond its range. The range is set by setDigitCount (),但 setSmallDecimalPoint () also influences it. If the display is set to hexadecimal, octal or binary, the integer equivalent of the value is displayed.
These digits and other symbols can be shown: 0/O, 1, 2, 3, 4, 5/S, 6, 7, 8, 9/g, minus, decimal point, A, B, C, D, E, F, h, H, L, o, P, r, u, U, Y, colon, degree sign (which is specified as single quote in the string) and space. QLCDNumber substitutes spaces for illegal characters.
It is not possible to retrieve the contents of a QLCDNumber object, although you can retrieve the numeric value with value (). If you really need the text, we recommend that you connect the signals that feed the display () slot to another slot as well and store the value there.
Incidentally, QLCDNumber is the very oldest part of Qt, tracing its roots back to a BASIC program on the Sinclair Spectrum .
另请参阅 QLabel , QFrame , 数字时钟范例 ,和 俄罗斯方块范例 .
This type determines how numbers are shown.
常量 | 值 | 描述 |
---|---|---|
QLCDNumber::Hex
|
0
|
Hexadecimal |
QLCDNumber::Dec
|
1
|
Decimal |
QLCDNumber::Oct
|
2
|
Octal |
QLCDNumber::Bin
|
3
|
Binary |
If the display is set to hexadecimal, octal or binary, the integer equivalent of the value is displayed.
This type determines the visual appearance of the QLCDNumber 小部件。
常量 | 值 | 描述 |
---|---|---|
QLCDNumber::Outline
|
0
|
gives raised segments filled with the background color. |
QLCDNumber::Filled
|
1
|
gives raised segments filled with the windowText color. |
QLCDNumber::Flat
|
2
|
gives flat segments filled with the windowText color. |
This property holds the current number of digits displayed
Corresponds to the current number of digits. If QLCDNumber::smallDecimalPoint is false, the decimal point occupies one digit position.
By default, this property contains a value of 5.
访问函数:
int | digitCount () const |
void | setDigitCount (int numDigits ) |
另请参阅 smallDecimalPoint .
This property holds the displayed value rounded to the nearest integer
This property corresponds to the nearest integer to the current value displayed by the LCDNumber. This is the value used for hexadecimal, octal and binary modes.
If the displayed value is not a number, the property has a value of 0.
默认情况下,此特性包含 0 值。
访问函数:
int | intValue () const |
void | display (const QString & s ) |
void | display (int num ) |
void | display (double num ) |
This property holds the current display mode (number base)
Corresponds to the current display mode, which is one of
Bin
,
Oct
,
Dec
(the default) and
Hex
.
Dec
mode can display floating point values, the other modes display the integer equivalent.
访问函数:
QLCDNumber::Mode | mode () const |
void | setMode (QLCDNumber::Mode) |
另请参阅 smallDecimalPoint (), setHexMode (), setDecMode (), setOctMode (),和 setBinMode ().
This property holds the style of the LCDNumber
Style | 结果 |
---|---|
Outline
|
Produces raised segments filled with the background color |
Filled
(this is the default).
|
Produces raised segments filled with the foreground color. |
Flat
|
Produces flat segments filled with the foreground color. |
Outline
and
Filled
will additionally use
QPalette::light
() 和
QPalette::dark
() for shadow effects.
访问函数:
QLCDNumber::SegmentStyle | segmentStyle () const |
void | setSegmentStyle (QLCDNumber::SegmentStyle) |
This property holds the style of the decimal point
If true the decimal point is drawn between two digit positions. Otherwise it occupies a digit position of its own, i.e. is drawn in a digit position. The default is false.
The inter-digit space is made slightly wider when the decimal point is drawn between the digits.
访问函数:
bool | smallDecimalPoint () const |
void | setSmallDecimalPoint (bool) |
另请参阅 mode .
This property holds the displayed value
This property corresponds to the current value displayed by the LCDNumber.
If the displayed value is not a number, the property has a value of 0.
默认情况下,此特性包含 0 值。
访问函数:
double | value () const |
void | display (const QString & s ) |
void | display (int num ) |
void | display (double num ) |
Constructs an LCD number, sets the number of digits to
numDigits
, the base to decimal, the decimal point mode to 'small' and the frame style to a raised box. The
segmentStyle
() 被设为
Filled
.
parent 自变量会被传递给 QFrame 构造函数。
另请参阅 setDigitCount () 和 setSmallDecimalPoint ().
Constructs an LCD number, sets the number of digits to 5, the base to decimal, the decimal point mode to 'small' and the frame style to a raised box. The
segmentStyle
() 被设为
Outline
.
parent 自变量会被传递给 QFrame 构造函数。
另请参阅 setDigitCount () 和 setSmallDecimalPoint ().
[slot]
void
QLCDNumber::
display
(
double
num
)
这是重载函数。
Displays the number num .
注意: Setter 函数对于特性 intValue . Setter function for property value .
[slot]
void
QLCDNumber::
display
(
int
num
)
这是重载函数。
Displays the number num .
注意: Setter 函数对于特性 intValue . Setter function for property value .
[slot]
void
QLCDNumber::
display
(const
QString
&
s
)
Displays the number represented by the string s .
This version of the function disregards mode () 和 smallDecimalPoint ().
These digits and other symbols can be shown: 0/O, 1, 2, 3, 4, 5/S, 6, 7, 8, 9/g, minus, decimal point, A, B, C, D, E, F, h, H, L, o, P, r, u, U, Y, colon, degree sign (which is specified as single quote in the string) and space. QLCDNumber substitutes spaces for illegal characters.
注意: Setter 函数对于特性 intValue . Setter function for property value .
[signal]
void
QLCDNumber::
overflow
()
此信号被发射每当 QLCDNumber is asked to display a too-large number or a too-long string.
It is never emitted by setDigitCount ().
[slot]
void
QLCDNumber::
setBinMode
()
调用 setMode (Bin). Provided for convenience (e.g. for connecting buttons to it).
另请参阅 setMode (), setHexMode (), setDecMode (), setOctMode (),和 mode ().
[slot]
void
QLCDNumber::
setDecMode
()
调用 setMode (Dec). Provided for convenience (e.g. for connecting buttons to it).
另请参阅 setMode (), setHexMode (), setOctMode (), setBinMode (),和 mode ().
[slot]
void
QLCDNumber::
setHexMode
()
调用 setMode (Hex). Provided for convenience (e.g. for connecting buttons to it).
另请参阅 setMode (), setDecMode (), setOctMode (), setBinMode (),和 mode ().
[slot]
void
QLCDNumber::
setOctMode
()
调用 setMode (Oct). Provided for convenience (e.g. for connecting buttons to it).
另请参阅 setMode (), setHexMode (), setDecMode (), setBinMode (),和 mode ().
[virtual]
QLCDNumber::
~QLCDNumber
()
Destroys the LCD number.
返回
true
if
num
is too big to be displayed in its entirety; otherwise returns
false
.
另请参阅 display (), digitCount (),和 smallDecimalPoint ().
这是重载函数。
返回
true
if
num
is too big to be displayed in its entirety; otherwise returns
false
.
另请参阅 display (), digitCount (),和 smallDecimalPoint ().
Returns the current number of digits.
注意: Getter function for property digitCount.
另请参阅 setDigitCount ().
[override virtual protected]
bool
QLCDNumber::
event
(
QEvent
*
e
)
重实现: QFrame::event (QEvent *e).
[override virtual protected]
void
QLCDNumber::
paintEvent
(
QPaintEvent
*)
重实现: QFrame::paintEvent (QPaintEvent *).
Sets the current number of digits to numDigits . Must be in the range 0..99.
注意: Setter 函数对于特性 digitCount .
另请参阅 digitCount ().
[override virtual]
QSize
QLCDNumber::
sizeHint
() const
重实现: QFrame::sizeHint () const.