Inherited by: QGLPixelBuffer, QGLFramebufferObject, QPrinter, QSvgGenerator, QPicture, QPixmap, QImage, QBitmap, QWidget, QDesktopWidget, QHelpSearchResultWidget, QHelpSearchQueryWidget, QComboBox, QCalendarWidget, QAbstractButton, QPushButton, QCommandLinkButton, QCheckBox, QWizardPage, QWebInspector, QLineEdit, QSvgWidget, Phonon.VolumeSlider, Phonon.VideoPlayer, Phonon.SeekSlider, QWorkspace, QToolButton, QFrame, QToolBox, QAbstractScrollArea, QGraphicsView, QDeclarativeView, QAbstractItemView, QTreeView, QHelpContentWidget, QTreeWidget, QHeaderView, QTableView, QTableWidget, QColumnView, QListView, QUndoView, QListWidget, QHelpIndexWidget, QToolBar, QRubberBand, QTabWidget, QStatusBar, QTabBar, Phonon.EffectWidget, QStackedWidget, QSplitterHandle, QAbstractSlider, QSlider, QDial, QSplitter, QAbstractSpinBox, QDateTimeEdit, QTimeEdit, QDateEdit, QSplashScreen, QDoubleSpinBox, QSpinBox, QSizeGrip, QScrollBar, QScrollArea, QRadioButton, QProgressBar, QDialog, QAbstractPrintDialog, QPrintDialog, QAbstractPageSetupDialog, QPageSetupDialog, QFileDialog, QWizard, QProgressDialog, QPrintPreviewDialog, QFontDialog, QMessageBox, QInputDialog, QErrorMessage, QColorDialog, QPrintPreviewWidget, QPlainTextEdit, QTextEdit, QTextBrowser, QMenuBar, QMenu, QMdiSubWindow, QMdiArea, QMainWindow, QLCDNumber, QLabel, QGroupBox, QFontComboBox, QFocusFrame, QDockWidget, QGLWidget, QDialogButtonBox, QWebView
The PySide.QtGui.QPaintDevice class is the base class of objects that can be painted.
A paint device is an abstraction of a two-dimensional space that can be drawn using a PySide.QtGui.QPainter . Its default coordinate system has its origin located at the top-left position. X increases to the right and Y increases downwards. The unit is one pixel.
The drawing capabilities of PySide.QtGui.QPaintDevice are currently implemented by the PySide.QtGui.QWidget , PySide.QtGui.QImage , PySide.QtGui.QPixmap , PySide.QtOpenGL.QGLPixelBuffer , PySide.QtGui.QPicture , and PySide.QtGui.QPrinter subclasses.
To implement support for a new backend, you must derive from PySide.QtGui.QPaintDevice and reimplement the virtual PySide.QtGui.QPaintDevice.paintEngine() function to tell PySide.QtGui.QPainter which paint engine should be used to draw on this particular device. Note that you also must create a corresponding paint engine to be able to draw on the device, i.e derive from PySide.QtGui.QPaintEngine and reimplement its virtual functions.
Warning
Qt requires that a PySide.QtGui.QApplication object exists before any paint devices can be created. Paint devices access window system resources, and these resources are not initialized before an application object is created.
The PySide.QtGui.QPaintDevice class provides several functions returning the various device metrics: The PySide.QtGui.QPaintDevice.depth() function returns its bit depth (number of bit planes). The PySide.QtGui.QPaintDevice.height() function returns its height in default coordinate system units (e.g. pixels for PySide.QtGui.QPixmap and PySide.QtGui.QWidget ) while PySide.QtGui.QPaintDevice.heightMM() returns the height of the device in millimeters. Similiarily, the PySide.QtGui.QPaintDevice.width() and PySide.QtGui.QPaintDevice.widthMM() functions return the width of the device in default coordinate system units and in millimeters, respectively. Alternatively, the protected PySide.QtGui.QPaintDevice.metric() function can be used to retrieve the metric information by specifying the desired QPaintDevice.PaintDeviceMetric as argument.
The PySide.QtGui.QPaintDevice.logicalDpiX() and PySide.QtGui.QPaintDevice.logicalDpiY() functions return the horizontal and vertical resolution of the device in dots per inch. The PySide.QtGui.QPaintDevice.physicalDpiX() and PySide.QtGui.QPaintDevice.physicalDpiY() functions also return the resolution of the device in dots per inch, but note that if the logical and physical resolution differ, the corresponding PySide.QtGui.QPaintEngine must handle the mapping. Finally, the PySide.QtGui.QPaintDevice.colorCount() function returns the number of different colors available for the paint device.
See also
PySide.QtGui.QPaintEngine PySide.QtGui.QPainter Coordinate System Paint System
Constructs a paint device. This constructor can be invoked only from subclasses of PySide.QtGui.QPaintDevice .
Describes the various metrics of a paint device.
Constant | Description |
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QPaintDevice.PdmWidth | The width of the paint device in default coordinate system units (e.g. pixels for PySide.QtGui.QPixmap and PySide.QtGui.QWidget ). See also PySide.QtGui.QPaintDevice.width() . |
QPaintDevice.PdmHeight | The height of the paint device in default coordinate system units (e.g. pixels for PySide.QtGui.QPixmap and PySide.QtGui.QWidget ). See also PySide.QtGui.QPaintDevice.height() . |
QPaintDevice.PdmWidthMM | The width of the paint device in millimeters. See also PySide.QtGui.QPaintDevice.widthMM() . |
QPaintDevice.PdmHeightMM | The height of the paint device in millimeters. See also PySide.QtGui.QPaintDevice.heightMM() . |
QPaintDevice.PdmNumColors | The number of different colors available for the paint device. See also PySide.QtGui.QPaintDevice.colorCount() . |
QPaintDevice.PdmDepth | The bit depth (number of bit planes) of the paint device. See also PySide.QtGui.QPaintDevice.depth() . |
QPaintDevice.PdmDpiX | The horizontal resolution of the device in dots per inch. See also PySide.QtGui.QPaintDevice.logicalDpiX() . |
QPaintDevice.PdmDpiY | The vertical resolution of the device in dots per inch. See also PySide.QtGui.QPaintDevice.logicalDpiY() . |
QPaintDevice.PdmPhysicalDpiX | The horizontal resolution of the device in dots per inch. See also PySide.QtGui.QPaintDevice.physicalDpiX() . |
QPaintDevice.PdmPhysicalDpiY | The vertical resolution of the device in dots per inch. See also PySide.QtGui.QPaintDevice.physicalDpiY() . |
See also
Return type: | PySide.QtCore.int |
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Returns the number of different colors available for the paint device. Since this value is an int, it will not be sufficient to represent the number of colors on 32 bit displays, in this case INT_MAX is returned instead.
Return type: | PySide.QtCore.int |
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Returns the bit depth (number of bit planes) of the paint device.
Return type: | PySide.QtCore.int |
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Returns the device type identifier, which is QInternal.Widget if the device is a PySide.QtGui.QWidget , QInternal.Pixmap if it’s a PySide.QtGui.QPixmap , QInternal.Printer if it’s a PySide.QtGui.QPrinter , QInternal.Picture if it’s a PySide.QtGui.QPicture , or QInternal.UnknownDevice in other cases.
Return type: | PySide.QtCore.int |
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Returns the height of the paint device in default coordinate system units (e.g. pixels for PySide.QtGui.QPixmap and PySide.QtGui.QWidget ).
See also
Return type: | PySide.QtCore.int |
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Returns the height of the paint device in millimeters. Due to platform limitations it may not be possible to use this function to determine the actual physical size of a widget on the screen.
See also
Return type: | PySide.QtCore.int |
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Returns the horizontal resolution of the device in dots per inch, which is used when computing font sizes. For X11, this is usually the same as could be computed from PySide.QtGui.QPaintDevice.widthMM() .
Note that if the PySide.QtGui.QPaintDevice.logicalDpiX() doesn’t equal the PySide.QtGui.QPaintDevice.physicalDpiX() , the corresponding PySide.QtGui.QPaintEngine must handle the resolution mapping.
Return type: | PySide.QtCore.int |
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Returns the vertical resolution of the device in dots per inch, which is used when computing font sizes. For X11, this is usually the same as could be computed from PySide.QtGui.QPaintDevice.heightMM() .
Note that if the PySide.QtGui.QPaintDevice.logicalDpiY() doesn’t equal the PySide.QtGui.QPaintDevice.physicalDpiY() , the corresponding PySide.QtGui.QPaintEngine must handle the resolution mapping.
Parameters: | metric – PySide.QtGui.QPaintDevice.PaintDeviceMetric |
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Return type: | PySide.QtCore.int |
Returns the metric information for the given paint device metric .
See also
QPaintDevice.PaintDeviceMetric
Return type: | PySide.QtCore.int |
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Use PySide.QtGui.QPaintDevice.colorCount() instead.
Returns the number of different colors available for the paint device. Since this value is an int, it will not be sufficient to represent the number of colors on 32 bit displays, in this case INT_MAX is returned instead.
Return type: | PySide.QtGui.QPaintEngine |
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Returns a pointer to the paint engine used for drawing on the device.
Return type: | PySide.QtCore.bool |
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Returns true if the device is currently being painted on, i.e. someone has called QPainter.begin() but not yet called QPainter.end() for this device; otherwise returns false.
See also
Return type: | PySide.QtCore.int |
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Returns the horizontal resolution of the device in dots per inch. For example, when printing, this resolution refers to the physical printer’s resolution. The logical DPI on the other hand, refers to the resolution used by the actual paint engine.
Note that if the PySide.QtGui.QPaintDevice.physicalDpiX() doesn’t equal the PySide.QtGui.QPaintDevice.logicalDpiX() , the corresponding PySide.QtGui.QPaintEngine must handle the resolution mapping.
Return type: | PySide.QtCore.int |
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Returns the horizontal resolution of the device in dots per inch. For example, when printing, this resolution refers to the physical printer’s resolution. The logical DPI on the other hand, refers to the resolution used by the actual paint engine.
Note that if the PySide.QtGui.QPaintDevice.physicalDpiY() doesn’t equal the PySide.QtGui.QPaintDevice.logicalDpiY() , the corresponding PySide.QtGui.QPaintEngine must handle the resolution mapping.
Return type: | PySide.QtCore.int |
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Returns the width of the paint device in default coordinate system units (e.g. pixels for PySide.QtGui.QPixmap and PySide.QtGui.QWidget ).
See also
Return type: | PySide.QtCore.int |
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Returns the width of the paint device in millimeters. Due to platform limitations it may not be possible to use this function to determine the actual physical size of a widget on the screen.
See also