Source code for qarbon.qt.gui.pixmapwidget

# ----------------------------------------------------------------------------
# This file is part of qarbon (http://qarbon.rtfd.org/)
#
# Copyright (c) 2013 European Synchrotron Radiation Facility, Grenoble, France
#
# Distributed under the terms of the GNU Lesser General Public License,
# either version 3 of the License, or (at your option) any later version.
# See LICENSE.txt for more info.
# ----------------------------------------------------------------------------

"""A widget that displays an image (pixmap).

You can adjust properties like the aligment inside the widget space, aspect
ratio and transformation mode (quality).

Example::

    from qarbon.external.qt import QtGui
    from qarbon.qt.gui.application import Application
    from qarbon.qt.gui.icon import Pixmap
    from qarbon.qt.gui.pixmapwidget import PixmapWidget

    app = Application()
    panel = QtGui.QWidget()
    layout = QtGui.QGridLayout()
    panel.setLayout(layout)
    img = PixmapWidget()
    layout.addWidget(img)

    img.setPixmap(Pixmap(":/led/led_red_on.png"))
    img.show()
    app.exec_()
"""

__all__ = ["PixmapWidget"]

from qarbon.external.qt import QtCore, QtGui


[docs]class PixmapWidget(QtGui.QWidget): """This widget displays an image (pixmap). By default the pixmap is scaled to the widget size and the aspect ratio is kept. The default alignment of the pixmap inside the widget space is horizontal left, vertical center.""" DefaultAlignment = QtCore.Qt.AlignLeft | QtCore.Qt.AlignVCenter DefaultAspectRatioMode = QtCore.Qt.KeepAspectRatio DefaultTransformationMode = QtCore.Qt.SmoothTransformation #: Signal emited when pixmap source changes pixmapChanged = QtCore.Signal() def __init__(self, parent=None): self._pixmap = QtGui.QPixmap() self._pixmapDrawn = None self._alignment = self.DefaultAlignment self._pixmapAspectRatioMode = self.DefaultAspectRatioMode self._pixmapTransformationMode = self.DefaultTransformationMode QtGui.QWidget.__init__(self, parent) def _getPixmap(self): if self._pixmapDrawn is None: self._pixmapDrawn = self.recalculatePixmap() return self._pixmapDrawn
[docs] def recalculatePixmap(self): origPixmap = self._pixmap if origPixmap.isNull(): return origPixmap return origPixmap.scaled(self.size(), self._pixmapAspectRatioMode, self._pixmapTransformationMode)
def _setDirty(self): self._pixmapDrawn = None
[docs] def paintEvent(self, paintEvent): """Overwrite the paintEvent from QWidget to draw the pixmap""" pixmap = self._getPixmap() w, h = self.width(), self.height() painter = QtGui.QPainter(self) painter.setRenderHint(QtGui.QPainter.Antialiasing) pw, ph = pixmap.width(), pixmap.height() align = self._alignment hAlign = align & QtCore.Qt.AlignHorizontal_Mask vAlign = align & QtCore.Qt.AlignVertical_Mask x, y = 0, 0 if hAlign & QtCore.Qt.AlignHCenter: x = (w - pw) / 2 elif hAlign & QtCore.Qt.AlignRight: x = w - pw if vAlign & QtCore.Qt.AlignVCenter: y = (h - ph) / 2 elif vAlign & QtCore.Qt.AlignBottom: y = h - ph x, y = max(0, x), max(0, y) painter.drawPixmap(x, y, pixmap)
[docs] def resizeEvent(self, event): self._setDirty() return QtGui.QWidget.resizeEvent(self, event)
[docs] def sizeHint(self): return self._pixmap.size() #-------------------------------------------------------------------------- # QT property definition #--------------------------------------------------------------------------
[docs] def getPixmap(self): """Returns the pixmap.Returns None if no pixmap is set. :return: the current pixmap :rtype: QtGui.QPixmap""" return self._pixmap
[docs] def setPixmap(self, pixmap): """Sets the pixmap for this widget. Setting it to None disables pixmap :param pixmap: the new pixmap :type pixmap: QtGui.QPixmap""" # make sure to make a copy because of bug in PyQt 4.4. This is actually # not copying the internal bitmap, just the qpixmap, so there is no # performance penalty here self._pixmap = QtGui.QPixmap(pixmap) self._setDirty() self.update() self.pixmapChanged.emit()
[docs] def resetPixmap(self): """Resets the pixmap for this widget.""" self.setPixmap(QtGui.QPixmap())
[docs] def getAspectRatioMode(self): """Returns the aspect ratio to apply when drawing the pixmap. :return: the current aspect ratio :rtype: QtCore.Qt.AspectRatioMode""" return self._pixmapAspectRatioMode
[docs] def setAspectRatioMode(self, aspect): """Sets the aspect ratio mode to apply when drawing the pixmap. :param pixmap: the new aspect ratio mode :type pixmap: QtCore.Qt.AspectRatioMode""" self._pixmapAspectRatioMode = aspect self._setDirty() self.update()
[docs] def resetAspectRatioMode(self): """Resets the aspect ratio mode to KeepAspectRatio""" self.setAspectRatioMode(self.DefaultAspectRatioMode)
[docs] def getTransformationMode(self): """Returns the transformation mode to apply when drawing the pixmap. :return: the current transformation mode :rtype: QtCore.Qt.TransformationMode""" return self._pixmapTransformationMode
[docs] def setTransformationMode(self, transformation): """Sets the transformation mode to apply when drawing the pixmap. :param pixmap: the new transformation mode :type pixmap: QtCore.Qt.TransformationMode""" self._pixmapTransformationMode = transformation self._setDirty() self.update()
[docs] def resetTransformationMode(self): """Resets the transformation mode to SmoothTransformation""" self.setTransformationMode(self.DefaultTransformationMode)
[docs] def getAlignment(self): """Returns the alignment to apply when drawing the pixmap. :return: the current alignment :rtype: QtCore.Qt.Alignment""" return self._alignment
[docs] def setAlignment(self, alignment): """Sets the alignment to apply when drawing the pixmap. :param pixmap: the new alignment :type pixmap: QtCore.Qt.Alignment""" self._alignment = alignment self.update()
[docs] def resetAlignment(self): """Resets the transformation mode to QtCore.Qt.AlignLeft | QtCore.Qt.AlignVCenter""" self.setAlignment(self.DefaultAlignment) #: This property holds the widget's pixmap #: #: **Access functions:** #: #: * :meth:`PixmapWidget.getPixmap` #: * :meth:`PixmapWidget.setPixmap` #: * :meth:`PixmapWidget.resetPixmap`
pixmap = QtCore.Property("QPixmap", getPixmap, setPixmap, resetPixmap, doc="the widget's pixmap") #: This property holds the widget's pixmap aspect ratio mode #: #: **Access functions:** #: #: * :meth:`PixmapWidget.getAspectRatioMode` #: * :meth:`PixmapWidget.setAspectRatioMode` #: * :meth:`PixmapWidget.resetAspectRatioMode` aspectRatioMode = QtCore.Property("Qt::AspectRatioMode", getAspectRatioMode, setAspectRatioMode, resetAspectRatioMode, doc="the widget's pixmap aspect ratio "\ "mode") #: This property holds the widget's pixmap transformation mode #: #: **Access functions:** #: #: * :meth:`PixmapWidget.getTransformationMode` #: * :meth:`PixmapWidget.setTransformationMode` #: * :meth:`PixmapWidget.resetTransformationMode` transformationMode = QtCore.Property("Qt::TransformationMode", getTransformationMode, setTransformationMode, resetTransformationMode, doc="the widget's pixmap "\ "transformation mode") #: This property holds the widget's pixmap alignment #: #: **Access functions:** #: #: * :meth:`PixmapWidget.getAlignment` #: * :meth:`PixmapWidget.setAlignment` #: * :meth:`PixmapWidget.resetAlignment` alignment = QtCore.Property("Qt::Alignment", getAlignment, setAlignment, resetAlignment, doc="the widget's pixmap alignment")
def main(): import sys import qarbon.config from qarbon.qt.gui.application import Application app = Application() M = 2 class QPixmapWidgetTestPanel(QtGui.QWidget): def __init__(self, parent=None): QtGui.QWidget.__init__(self, parent) panel_l = QtGui.QVBoxLayout() self.setLayout(panel_l) panel_l.setContentsMargins(M, M, M, M) panel_l.setSpacing(M) w = PixmapWidget() display_panel = QtGui.QGroupBox("Pixmap Widget Display") display_l = QtGui.QHBoxLayout() display_l.setContentsMargins(M, M, M, M) display_l.setSpacing(M) display_panel.setLayout(display_l) display_l.addWidget(w, 1) control_panel = QtGui.QGroupBox("Control Panel") control_l = QtGui.QFormLayout() control_l.setContentsMargins(M, M, M, M) control_l.setSpacing(M) control_panel.setLayout(control_l) pixmap_widget = QtGui.QLineEdit() ratio_widget = QtGui.QComboBox() transformation_widget = QtGui.QComboBox() halign_widget = QtGui.QComboBox() valign_widget = QtGui.QComboBox() control_l.addRow("pixmap:", pixmap_widget) control_l.addRow("Aspect ratio mode:", ratio_widget) control_l.addRow("Transformation mode:", transformation_widget) control_l.addRow("Horiz. alignment:", halign_widget) control_l.addRow("Vert. alignment:", valign_widget) panel_l.addWidget(display_panel, 1) panel_l.addWidget(control_panel, 0) ratio_widget.addItems(["Ignore", "Keep", "Keep by expanding"]) transformation_widget.addItem("Fast", QtCore.Qt.FastTransformation) transformation_widget.addItem("Smooth", QtCore.Qt.SmoothTransformation) halign_widget.addItem("Left", QtCore.Qt.AlignLeft) halign_widget.addItem("Center", QtCore.Qt.AlignHCenter) halign_widget.addItem("Right", QtCore.Qt.AlignRight) valign_widget.addItem("Top", QtCore.Qt.AlignTop) valign_widget.addItem("Center", QtCore.Qt.AlignVCenter) valign_widget.addItem("Bottom", QtCore.Qt.AlignBottom) pixmap_widget.textChanged.connect(self.changePixmap) ratio_widget.currentIndexChanged.connect(self.changeAspectRatio) halign_widget.currentIndexChanged.connect(self.changeAlignment) valign_widget.currentIndexChanged.connect(self.changeAlignment) self.w = w self.w_pixmap = pixmap_widget self.w_aspect_ratio = ratio_widget self.w_transformation = transformation_widget self.w_halign = halign_widget self.w_valign = valign_widget pixmap_widget.setText(qarbon.config.NAMESPACE + \ ":/led/led_red_on.png") ratio_widget.setCurrentIndex(1) transformation_widget.setCurrentIndex(1) halign_widget.setCurrentIndex(0) valign_widget.setCurrentIndex(1) def changePixmap(self, name): self.w.pixmap = QtGui.QPixmap(name) def changeAspectRatio(self, i): v = QtCore.Qt.IgnoreAspectRatio if i == 1: v = QtCore.Qt.KeepAspectRatio elif i == 2: v = QtCore.Qt.KeepAspectRatioByExpanding self.w.setAspectRatioMode(v) def changeTransformationMode(self, i): v = QtCore.Qt.FastTransformation if i == 1: v = QtCore.Qt.SmoothTransformation self.w.setTransformationMode(v) def changeAlignment(self, i): halign = self.w_halign.itemData(self.w_halign.currentIndex()) valign = self.w_valign.itemData(self.w_valign.currentIndex()) self.w.alignment = halign | valign panel = QtGui.QWidget() layout = QtGui.QGridLayout() panel.setLayout(layout) layout.setContentsMargins(M, M, M, M) layout.setSpacing(M) p1 = QPixmapWidgetTestPanel() layout.addWidget(p1, 0, 0) panel.show() sys.exit(app.exec_()) if __name__ == "__main__": main()