本文整理汇总了Python中qtpy.QtGui.QPixmap.isNull方法的典型用法代码示例。如果您正苦于以下问题：Python QPixmap.isNull方法的具体用法？Python QPixmap.isNull怎么用？Python QPixmap.isNull使用的例子？那么恭喜您, 这里精选的方法代码示例或许可以为您提供帮助。您也可以进一步了解该方法所在类qtpy.QtGui.QPixmap的用法示例。
在下文中一共展示了QPixmap.isNull方法的1个代码示例，这些例子默认根据受欢迎程度排序。您可以为喜欢或者感觉有用的代码点赞，您的评价将有助于系统推荐出更棒的Python代码示例。
示例1: imageFiles
# 需要导入模块: from qtpy.QtGui import QPixmap [as 别名]
# 或者: from qtpy.QtGui.QPixmap import isNull [as 别名]
def imageFiles(self, new_files):
"""
JSON-formatted dictionary keyed on states (integers), with filenames
of the image file to display for the state.
Parameters
----------
new_files : str
"""
self._state_images_string = str(new_files)
try:
new_file_dict = json.loads(self._state_images_string)
except Exception:
self._state_images = {}
return
self._sizeHint = QSize(0, 0)
for (state, filename) in new_file_dict.items():
if is_pydm_app():
try:
file_path = self.app.get_path(filename)
except Exception as e:
logger.exception("Couldn't get file with path %s", filename)
file_path = filename
else:
file_path = filename
# First, lets try SVG. We have to try SVG first, otherwise
# QPixmap will happily load the SVG and turn it into a raster image.
# Really annoying: We have to try to load the file as SVG,
# and we expect it will fail often (because many images aren't SVG).
# Qt prints a warning message to stdout any time SVG loading fails.
# So we have to temporarily silence Qt warning messages here.
qInstallMessageHandler(self.qt_message_handler)
svg = QSvgRenderer()
svg.repaintNeeded.connect(self.update)
if svg.load(file_path):
self._state_images[int(state)] = (filename, svg)
self._sizeHint = self._sizeHint.expandedTo(svg.defaultSize())
qInstallMessageHandler(None)
continue
qInstallMessageHandler(None)
# SVG didn't work, lets try QPixmap
image = QPixmap(file_path)
if not image.isNull():
self._state_images[int(state)] = (filename, image)
self._sizeHint = self._sizeHint.expandedTo(image.size())
continue
# If we get this far, the file specified could not be loaded at all.
logger.error("Could not load image: {}".format(filename))
self._state_images[int(state)] = (filename, None)