warning_callback property

DocumentBase.warning_callback property

Called during various document processing procedures when an issue is detected that might result in data or formatting fidelity loss.

@property
def warning_callback(self) -> aspose.words.IWarningCallback:
    ...

@warning_callback.setter
def warning_callback(self, value: aspose.words.IWarningCallback):
    ...

Remarks

Document may generate warnings at any stage of its existence, so it’s important to setup warning callback as early as possible to avoid the warnings loss. E.g. such properties as Document.page_count actually build the document layout which is used later for rendering, and the layout warnings may be lost if warning callback is specified just for the rendering calls later.

Examples

Shows how to use the IWarningCallback interface to monitor font substitution warnings.

doc = aw.Document()
builder = aw.DocumentBuilder(doc=doc)
builder.font.name = 'Times New Roman'
builder.writeln('Hello world!')
callback = self.FontSubstitutionWarningCollector()
doc.warning_callback = callback
# Store the current collection of font sources, which will be the default font source for every document
# for which we do not specify a different font source.
original_font_sources = aw.fonts.FontSettings.default_instance.get_fonts_sources()
# For testing purposes, we will set Aspose.Words to look for fonts only in a folder that does not exist.
aw.fonts.FontSettings.default_instance.set_fonts_folder('', False)
# When rendering the document, there will be no place to find the "Times New Roman" font.
# This will cause a font substitution warning, which our callback will detect.
doc.save(file_name=ARTIFACTS_DIR + 'FontSettings.SubstitutionWarning.pdf')
aw.fonts.FontSettings.default_instance.set_fonts_sources(sources=original_font_sources)
self.assertEqual(1, callback.font_substitution_warnings.count)
self.assertTrue(callback.font_substitution_warnings[0].warning_type == aw.WarningType.FONT_SUBSTITUTION)
self.assertTrue(callback.font_substitution_warnings[0].description == "Font 'Times New Roman' has not been found. Using 'Fanwood' font instead. Reason: first available font.")

Shows how to set the property for finding the closest match for a missing font from the available font sources.

# Open a document that contains text formatted with a font that does not exist in any of our font sources.
doc = aw.Document(file_name=MY_DIR + 'Missing font.docx')
# Assign a callback for handling font substitution warnings.
warning_collector = aw.WarningInfoCollection()
doc.warning_callback = warning_collector
# Set a default font name and enable font substitution.
font_settings = aw.fonts.FontSettings()
font_settings.substitution_settings.default_font_substitution.default_font_name = 'Arial'
font_settings.substitution_settings.font_info_substitution.enabled = True
# Original font metrics should be used after font substitution.
doc.layout_options.keep_original_font_metrics = True
# We will get a font substitution warning if we save a document with a missing font.
doc.font_settings = font_settings
doc.save(file_name=ARTIFACTS_DIR + 'FontSettings.EnableFontSubstitution.pdf')
for info in warning_collector:
    if info.warning_type == aw.WarningType.FONT_SUBSTITUTION:
        print(info.description)

Shows how to use the IWarningCallback interface to monitor font substitution warnings (FontSubstitutionWarningCollector).

class FontSubstitutionWarningCollector(aw.IWarningCallback):

    def __init__(self):
        self.font_substitution_warnings = aw.WarningInfoCollection()

    def warning(self, info):
        if info.warning_type == aw.WarningType.FONT_SUBSTITUTION:
            self.font_substitution_warnings.warning(info)

warning_callback property

DocumentBase.warning_callback property

Remarks

Examples

See Also