QResource¶
Synopsis¶
Functions¶
def
absoluteFilePath
()def
children
()def
data
()def
fileName
()def
isCompressed
()def
isDir
()def
isFile
()def
isValid
()def
lastModified
()def
locale
()def
setFileName
(file)def
setLocale
(locale)def
size
()
Static functions¶
def
addSearchPath
(path)def
registerResource
(rccFilename[, resourceRoot=”“])def
registerResourceData
(rccData[, resourceRoot=”“])def
searchPaths
()def
unregisterResource
(rccFilename[, resourceRoot=”“])def
unregisterResourceData
(rccData[, resourceRoot=”“])
Detailed Description¶
QResource
is an object that represents a set of data (and possibly children) relating to a single resource entity.QResource
gives direct access to the bytes in their raw format. In this way direct access allows reading data without buffer copying or indirection. Indirection is often useful when interacting with the resource entity as if it is a file, this can be achieved withQFile
. The data and children behind aQResource
are normally compiled into an application/library, but it is also possible to load a resource at runtime. When loaded at run time the resource file will be loaded as one big set of data and then given out in pieces via references into the resource tree.A
QResource
can either be loaded with an absolute path, either treated as a file system rooted with a/
character, or in resource notation rooted with a:
character. A relative resource can also be opened which will be found in the list of paths returned bysearchPaths()
.A
QResource
that is representing a file will have data backing it, this data can possibly be compressed, in which caseqUncompress()
must be used to access the real data; this happens implicitly when accessed through aQFile
. AQResource
that is representing a directory will have only children and no data.
Dynamic Resource Loading¶
A resource can be left out of an application’s binary and loaded when it is needed at run-time by using the
registerResource()
function. The resource file passed intoregisterResource()
must be a binary resource as created by rcc. Further information about binary resources can be found in The Qt Resource System documentation.This can often be useful when loading a large set of application icons that may change based on a setting, or that can be edited by a user and later recreated. The resource is immediately loaded into memory, either as a result of a single file read operation, or as a memory mapped file.
This approach can prove to be a significant performance gain as only a single file will be loaded, and pieces of data will be given out via the path requested in
setFileName()
.The
unregisterResource()
function removes a reference to a particular file. If there areQResource
objects that currently reference resources related to the unregistered file, they will continue to be valid but the resource file itself will be removed from the resource roots, and thus no furtherQResource
can be created pointing into this resource data. The resource itself will be unmapped from memory when the lastQResource
that points to it is destroyed.See also
-
class
QResource
([file=""[, locale=QLocale()]])¶ - param locale
- param file
unicode
Constructs a
QResource
pointing tofile
.locale
is used to load a specific localization of a resource data.See also
-
PySide2.QtCore.QResource.
absoluteFilePath
()¶ - Return type
unicode
Returns the real path that this
QResource
represents, if the resource was found via thesearchPaths()
it will be indicated in the path.See also
-
static
PySide2.QtCore.QResource.
addSearchPath
(path)¶ - Parameters
path – unicode
Use
addSearchPath()
with a prefix instead.Adds
path
to the search paths searched in to find resources that are not specified with an absolute path. Thepath
must be an absolute path (start with/
).The default search path is to search only in the root (
:/
). The last path added will be consulted first upon nextQResource
creation.
-
PySide2.QtCore.QResource.
children
()¶ - Return type
list of strings
Returns a list of all resources in this directory, if the resource represents a file the list will be empty.
See also
-
PySide2.QtCore.QResource.
data
()¶ - Return type
PyObject
Returns a read only buffer object pointing to the segment of data that this resource represents. If the resource is compressed the data returns is compressed and qUncompress() must be used to access the data. If the resource is a directory None is returned.
-
PySide2.QtCore.QResource.
fileName
()¶ - Return type
unicode
Returns the full path to the file that this
QResource
represents as it was passed.See also
-
PySide2.QtCore.QResource.
isCompressed
()¶ - Return type
bool
Returns
true
if the resource represents a file and the data backing it is in a compressed format, false otherwise.
-
PySide2.QtCore.QResource.
isDir
()¶ - Return type
bool
Returns
true
if the resource represents a directory and thus may havechildren()
in it, false if it represents a file.See also
-
PySide2.QtCore.QResource.
isFile
()¶ - Return type
bool
Returns
true
if the resource represents a file and thus has data backing it, false if it represents a directory.See also
-
PySide2.QtCore.QResource.
isValid
()¶ - Return type
bool
Returns
true
if the resource really exists in the resource hierarchy, false otherwise.
-
PySide2.QtCore.QResource.
lastModified
()¶ - Return type
Returns the date and time when the file was last modified before packaging into a resource.
-
PySide2.QtCore.QResource.
locale
()¶ - Return type
Returns the locale used to locate the data for the
QResource
.See also
-
static
PySide2.QtCore.QResource.
registerResource
(rccFilename[, resourceRoot=""])¶ - Parameters
rccFilename – unicode
resourceRoot – unicode
- Return type
bool
-
static
PySide2.QtCore.QResource.
registerResourceData
(rccData[, resourceRoot=""])¶ - Parameters
rccData –
uchar
resourceRoot – unicode
- Return type
bool
-
static
PySide2.QtCore.QResource.
searchPaths
()¶ - Return type
list of strings
Use
searchPaths()
instead.Returns the current search path list. This list is consulted when creating a relative resource.
See also
-
PySide2.QtCore.QResource.
setFileName
(file)¶ - Parameters
file – unicode
Sets a
QResource
to point tofile
.file
can either be absolute, in which case it is opened directly, if relative then the file will be tried to be found insearchPaths()
.See also
-
PySide2.QtCore.QResource.
setLocale
(locale)¶ - Parameters
locale –
QLocale
Sets a
QResource
to only load the localization of resource to forlocale
. If a resource for the specific locale is not found then the C locale is used.See also
-
PySide2.QtCore.QResource.
size
()¶ - Return type
qint64
Returns the size of the data backing the resource.
-
static
PySide2.QtCore.QResource.
unregisterResource
(rccFilename[, resourceRoot=""])¶ - Parameters
rccFilename – unicode
resourceRoot – unicode
- Return type
bool
-
static
PySide2.QtCore.QResource.
unregisterResourceData
(rccData[, resourceRoot=""])¶ - Parameters
rccData –
uchar
resourceRoot – unicode
- Return type
bool
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