book

Python Programming with Design Patterns

by James W. Cooper

December 2021

Intermediate to advanced

352 pages

10h

English

Addison-Wesley Professional

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Book Organization

The tkinter LibraryGitHub
The Class __init__ MethodVariables Inside a ClassCollections of ClassesInheritanceDerived Classes Created with Revised MethodsMultiple InheritanceDrawing a Rectangle and a SquareVisibility of VariablesTypes in PythonSummaryPrograms on GitHub
Importing Fewer NamesCreating an Object-Oriented VersionUsing Message BoxesUsing File DialogsUnderstanding Options for the Pack Layout ManagerUsing the ttk LibrariesResponding to User InputApplying Colors in tkinterCreating Radio ButtonsCommunicating Between ClassesUsing the Grid LayoutCreating CheckbuttonsAdding Menus to WindowsUsing the LabelFrameMoving OnExamples on GitHub
Creating a ListboxUsing a ComboboxThe Treeview WidgetMoving OnExample Code on GitHub
Defining Design PatternsThe Learning ProcessNotes on Object-Oriented ApproachesPython Design PatternsReferences
How a Factory WorksSample CodeThe Two SubclassesBuilding the Simple FactoryFactory Patterns in Math ComputationPrograms on GitHubThought Questions
The Swimmer ClassThe Event ClassesStraight SeedingOur Seeding ProgramOther FactoriesWhen to Use a Factory MethodPrograms on GitHub
A GardenMaker FactoryHow the User Interface WorksConsequences of the Abstract Factory PatternThought QuestionsCode on GitHub
Throwing the ExceptionCreating an Instance of the ClassStatic Classes As Singleton PatternsFinding the Singletons in a Large ProgramOther Consequences of the Singleton PatternSample Code on GitHub
An Investment TrackerCalling the BuildersDisplaying the Selected SecuritiesConsequences of the Builder PatternThought QuestionsSample Code on GitHub
Cloning in PythonUsing the PrototypeConsequences of the Prototype PatternSample Code on GitHub
Moving Data Between ListsMaking an AdapterPrograms on GitHub
Creating the User InterfaceExtending the BridgeConsequences of the Bridge PatternPrograms on GitHub
An Implementation of a CompositeSalary ComputationThe Employee ClassesBuilding the Employee TreePrinting the Employee TreeCreating a Treeview of the CompositeUsing Doubly Linked ListsConsequences of the Composite PatternA Simple CompositeOther Implementation IssuesPrograms on GitHub
Decorating a ButtonUsing a DecoratorUsing Nonvisual DecoratorsThe dataclass DecoratorUsing dataclass with Default ValuesDecorators, Adapters, and CompositesConsequences of the Decorator PatternPrograms on GitHub
Building the Façade ClassesCreating Databases and TablesUsing the SQLite VersionConsequences of the FaçadePrograms on GitHubNotes on MySQLUsing SQLiteReferences
What Are Flyweights?Example CodeCopy-on-Write ObjectsProgram on GitHub
Using the Pillow Image LibraryDisplaying an Image Using PILUsing Threads to Handle Image LoadingLogging from ThreadsCopy-on-WriteComparing Related PatternsPrograms on GitHub
When to Use the ChainSample CodeThe ListboxesProgramming a Help SystemReceiving the Help CommandThe First CaseA Chain or a Tree?Kinds of RequestsConsequences of the Chain of ResponsibilityPrograms on GitHub
When to Use the Command PatternCommand ObjectsA Keyboard ExampleCalling the Command ObjectsBuilding Command ObjectsThe Command PatternConsequences of the Command PatternProviding the Undo FunctionSummaryReferencesPrograms on GitHub
When to Use an InterpreterWhere the Pattern Can Be HelpfulA Simple Report ExampleInterpreting the LanguageHow Parsing WorksThe Console InterfaceThe User InterfaceConsequences of the Interpreter PatternPrograms on GitHub
Why We Use IteratorsIterators in PythonA Fibonacci IteratorFiltered IteratorsThe Iterator GeneratorA Fibonacci IteratorGenerators in ClassesConsequences of the Iterator PatternPrograms on GitHub
An Example SystemInteractions Between ControlsSample CodeMediators and Command ObjectsConsequences of the Mediator PatternSingle Interface MediatorsPrograms on GitHub
When to Use a MementoSample CodeConsequences of the Memento PatternProgram on GitHub
Example Program for Watching Colors ChangeThe Message to the MediaConsequences of the Observer PatternPrograms on GitHub
Sample CodeSwitching Between StatesHow the Mediator Interacts with the StateManagerConsequences of the State PatternState TransitionsProgram on GitHub
Why We Use the Strategy PatternSample CodeThe ContextThe Program CommandsThe Line and Bar Graph StrategiesConsequences of the Strategy PatternPrograms on GitHub
Why We Use Template patternsKinds of Methods in a Template ClassSample CodeThe Triangle Drawing ProgramTemplates and CallbacksSummary and ConsequencesExample Code on GitHub
When to Use the Visitor PatternWorking with the Visitor PatternSample CodeVisiting Several ClassesBosses Are Employees, TooDouble DispatchingTraversing a Series of ClassesConsequences of the Visitor PatternExample Code on GitHub
Data TypesNumeric ConstantsStringsCharacter ConstantsVariablesComplex NumbersInteger DivisionMultiple Equal Signs for InitializationA Simple Python ProgramCompiling and Running This ProgramArithmetic OperatorsCombined Arithmetic and Assignment StatementsComparison OperatorsThe input StatementPEP 8 StandardsString MethodsExamples on GitHub
elif is “else if”Combining ConditionsThe Most Common MistakeLooping Statements in PythonUsing break and continuePython Line LengthThe print FunctionFormatting NumbersFormatting DatesUsing the Python match FunctionReferenceMoving OnSample Code on GitHub
IDLEThonnyPyCharmVisual StudioOther Development EnvironmentsCommand-Line ExecutionCPython, IPython, and Jython
SlicingSlicing StringsChanging List ContentsCopying a ListReading FilesHandling ExceptionsUsing DictionariesUsing TuplesUsing SetsUsing the map FunctionWriting a Complete ProgramUsing List ComprehensionSample Programs on GitHub
Returning a TupleWhere Does the Program Start?SummaryPrograms on GitHub
If You Have Python InstalledCreating an Executable Python ProgramCommand-Line Arguments

Content preview from Python Programming with Design Patterns

27 The State Pattern

The State pattern is used when you want to have an object represent the state of your application and then switch application states by switching objects. For example, you could have an enclosing class switch between a number of related contained classes and then pass method calls on to the current contained class. Design Patterns suggests that the State pattern switch between internal classes in such a way that the enclosing object appears to change its class. In Python, at least, this is a bit of an exaggeration, but the actual purpose to which the classes are put can change significantly.

Many programmers have experienced creating a class that performs slightly different computations or displays different information ...

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Publisher Resources

ISBN: 9780137579921

Python Programming with Design Patterns

by James W. Cooper

27

The State Pattern

Become an O’Reilly member and get unlimited access to this title plus top books and audiobooks from O’Reilly and nearly 200 top publishers, thousands of courses curated by job role, 150+ live events each month,
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27

The State Pattern

Become an O’Reilly member and get unlimited access to this title plus top books and audiobooks from O’Reilly and nearly 200 top publishers, thousands of courses curated by job role, 150+ live events each month,and much more.

You might also like

Python Architecture Patterns

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Publisher Resources

Become an O’Reilly member and get unlimited access to this title plus top books and audiobooks from O’Reilly and nearly 200 top publishers, thousands of courses curated by job role, 150+ live events each month,
and much more.