Find item in QApplication by only the objectname

Question

i want to find any object by a objectname string name inside of the QApplication

Something like

QApplication.instance().findByClassName(\"codeEditor         


        

Answer 1

In Python, this can be done for any class using the gc module. It provides a method for retrieving the references of all objects tracked by the garbage-collector. This is obviously a quite inefficient approach, but it does (almost) guarantee that any type of object can be found.

Here's a function to get a list of all QObject instances either by class-name or object-name:

def getObjects(name, cls=True):
    objects = []
    for obj in gc.get_objects():
        if (isinstance(obj, QtCore.QObject) and
            ((cls and obj.inherits(name)) or
             (not cls and obj.objectName() == name))):
            objects.append(obj)
    return objects

This is only really a debugging tool, though - for a large application, there could easily be several hundred thousand objects to check.

If you only need objects which are subclasses of QWidget, use this function:

def getWidgets(name, cls=True):
    widgets = []
    for widget in QtGui.QApplication.allWidgets():
        if ((cls and widget.inherits(name)) or
            (not cls and widget.objectName() == name)):
            widgets.append(widget)
    return widgets

PS:

If you want to find all objects which are subclasses of QObject, this can only be achieved if you can somehow ensure that all the instances in your application have a valid parent (which, by definition, must also be a QObject). With that in place, you can then use root_object.findChildren(QObject) to get the full list. It is also possible to use findChild or findChildren to search for individual objects by object-name (optionally using a regular-expression, if desirable).