The QTextLength class encapsulates the different types of length used in a QTextDocument . 更多...
头: | #include <QTextLength> |
qmake: | QT += gui |
注意: 此类的所有函数 可重入 .
enum | Type { VariableLength, FixedLength, PercentageLength } |
QTextLength () | |
QTextLength (QTextLength::Type type , qreal value ) | |
qreal | rawValue () const |
QTextLength::Type | type () const |
qreal | value (qreal maximumLength ) const |
QVariant | operator QVariant () const |
bool | operator!= (const QTextLength & other ) const |
bool | operator== (const QTextLength & other ) const |
The QTextLength class encapsulates the different types of length used in a QTextDocument .
When we specify a value for the length of an element in a text document, we often need to provide some other information so that the length is used in the way we expect. For example, when we specify a table width, the value can represent a fixed number of pixels, or it can be a percentage value. This information changes both the meaning of the value and the way it is used.
Generally, this class is used to specify table widths. These can be specified either as a fixed amount of pixels, as a percentage of the containing frame's width, or by a variable width that allows it to take up just the space it requires.
另请参阅 QTextTable .
This enum describes the different types a length object can have.
常量 | 值 | 描述 |
---|---|---|
QTextLength::VariableLength
|
0
|
The width of the object is variable |
QTextLength::FixedLength
|
1
|
The width of the object is fixed |
QTextLength::PercentageLength
|
2
|
The width of the object is in percentage of the maximum width |
另请参阅 type ().
Constructs a new length object which represents a variable size.
Constructs a new length object of the given type and value .
Returns the constraint value that is specific for the type of the length. If the length is QTextLength::PercentageLength then the raw value is in percent, in the range of 0 to 100. If the length is QTextLength::FixedLength then that fixed amount is returned. For variable lengths, zero is returned.
Returns the type of this length object.
另请参阅 QTextLength::Type .
Returns the effective length, constrained by the type of the length object and the specified maximumLength .
另请参阅 type ().
Returns the text length as a QVariant
返回
true
if this text length is different from the
other
text length.
返回
true
if this text length is the same as the
other
text length.