diff --git a/.idea/codeStyles/codeStyleConfig.xml b/.idea/codeStyles/codeStyleConfig.xml deleted file mode 100644 index a55e7a1..0000000 --- a/.idea/codeStyles/codeStyleConfig.xml +++ /dev/null @@ -1,5 +0,0 @@ - - - - \ No newline at end of file diff --git a/.idea/libraries/Dart_SDK.xml b/.idea/libraries/Dart_SDK.xml deleted file mode 100644 index 2255dbd..0000000 --- a/.idea/libraries/Dart_SDK.xml +++ /dev/null @@ -1,26 +0,0 @@ - - - - - - - - - - - - - - - - - - - - - - - - - - \ No newline at end of file diff --git a/.idea/misc.xml b/.idea/misc.xml deleted file mode 100644 index 639900d..0000000 --- a/.idea/misc.xml +++ /dev/null @@ -1,6 +0,0 @@ - - - - - - \ No newline at end of file diff --git a/.idea/modules.xml b/.idea/modules.xml deleted file mode 100644 index d08c8ed..0000000 --- a/.idea/modules.xml +++ /dev/null @@ -1,8 +0,0 @@ - - - - - - - - \ No newline at end of file diff --git a/.idea/vcs.xml b/.idea/vcs.xml deleted file mode 100644 index 94a25f7..0000000 --- a/.idea/vcs.xml +++ /dev/null @@ -1,6 +0,0 @@ - - - - - - \ No newline at end of file diff --git a/02_built_in_data_types.dart b/02_built_in_data_types.dart index 5f1e485..c7880fa 100644 --- a/02_built_in_data_types.dart +++ b/02_built_in_data_types.dart @@ -1,27 +1,27 @@ +// ignore_for_file: unused_local_variable void main(List arguments) { + // Numbers: int + int score = 23; + var count = 23; // It is inferred as integer automatically by compiler + int hexValue = 0xEADEBAEE; - // Numbers: int - int score = 23; - var count = 23; // It is inferred as integer automatically by compiler - int hexValue = 0xEADEBAEE; + // Numbers: double + double percentage = 93.4; + var percent = 82.533; + double exponents = 1.42e5; - // Numbers: double - double percentage = 93.4; - var percent = 82.533; - double exponents = 1.42e5; + // Strings + String name = "Henry"; + var company = "Google"; - // Strings - String name = "Henry"; - var company = "Google"; + // Boolean + bool isValid = true; + var isAlive = false; - // Boolean - bool isValid = true; - var isAlive = false; + print(score); + print(exponents); - print(score); - print(exponents); - - // NOTE: All data types in Dart are Objects. - // Therefore, their initial value is by default 'null' + // NOTE: All data types in Dart are Objects. + // Therefore, their initial value is by default 'null' } diff --git a/03_string_and_string_interpolation.dart b/03_string_and_string_interpolation.dart index 3132427..fb3814d 100644 --- a/03_string_and_string_interpolation.dart +++ b/03_string_and_string_interpolation.dart @@ -1,32 +1,30 @@ +// ignore_for_file: unused_local_variable void main() { + // Literals + var isCool = true; + int x = 2; + "John"; + 4.5; - // Literals - var isCool = true; - int x = 2; - "John"; - 4.5; + // Various ways to define String Literals in Dart + String s1 = 'Single'; + String s2 = "Double"; + String s3 = 'It\'s easy'; + String s4 = "It's easy"; - // Various ways to define String Literals in Dart - String s1 = 'Single'; - String s2 = "Double"; - String s3 = 'It\'s easy'; - String s4 = "It's easy"; + String s5 = 'This is going to be a very long String. ' + 'This is just a sample String demo in Dart Programming Language'; - String s5 = 'This is going to be a very long String. ' - 'This is just a sample String demo in Dart Programming Language'; + // String Interpolation : Use ["My name is $name"] instead of ["My name is " + name] + String name = "Kevin"; + print("My name is $name"); + print("The number of characters in String Kevin is ${name.length}"); - // String Interpolation : Use ["My name is $name"] instead of ["My name is " + name] - String name = "Kevin"; + int l = 20; + int b = 10; - print("My name is $name"); - print("The number of characters in String Kevin is ${name.length}"); - - - int l = 20; - int b = 10; - - print("The sum of $l and $b is ${l + b}"); - print("The area of rectangle with length $l and breadth $b is ${l * b}"); + print("The sum of $l and $b is ${l + b}"); + print("The area of rectangle with length $l and breadth $b is ${l * b}"); } diff --git a/04_constants.dart b/04_constants.dart index f171c16..9063da9 100644 --- a/04_constants.dart +++ b/04_constants.dart @@ -1,19 +1,18 @@ +// ignore_for_file: unused_local_variable void main() { + // final + final cityName = 'Mumbai'; + // name = 'Peter'; // Throws an error - // final - final cityName = 'Mumbai'; - // name = 'Peter'; // Throws an error + final String countryName = 'India'; - final String countryName = 'India'; - - // const - const PI = 3.14; - const double gravity = 9.8; + // const + const PI = 3.14; + const double gravity = 9.8; } class Circle { - - final color = 'Red'; - static const PI = 3.14; + final color = 'Red'; + static const PI = 3.14; } diff --git a/06_conditional_expressions.dart b/06_conditional_expressions.dart index c0f3751..c790688 100644 --- a/06_conditional_expressions.dart +++ b/06_conditional_expressions.dart @@ -1,26 +1,22 @@ - void main() { + // Conditional Expressions - // Conditional Expressions - - // 1. condition ? exp1 : exp2 - // If condition is true, evaluates expr1 (and returns its value); - // otherwise, evaluates and returns the value of expr2. - - int a = 2; - int b = 3; - - int smallNumber = a < b ? a : b; - print("$smallNumber is smaller"); + // 1. condition ? exp1 : exp2 + // If condition is true, evaluates expr1 (and returns its value); + // otherwise, evaluates and returns the value of expr2. + int a = 2; + int b = 3; + int smallNumber = a < b ? a : b; + print("$smallNumber is smaller"); - // 2. exp1 ?? exp2 - // If expr1 is non-null, returns its value; otherwise, evaluates and - // returns the value of expr2. + // 2. exp1 ?? exp2 + // If expr1 is non-null, returns its value; otherwise, evaluates and + // returns the value of expr2. - String name = null; + var name = null; - String nameToPrint = name ?? "Guest User"; - print(nameToPrint); + String nameToPrint = name ?? "Guest User"; + print(nameToPrint); } diff --git a/07_switch_and_case.dart b/07_switch_and_case.dart index ce90445..c144c91 100644 --- a/07_switch_and_case.dart +++ b/07_switch_and_case.dart @@ -1,28 +1,26 @@ - void main() { + // Switch Case Statements: Applicable for only 'int' and 'String' - // Switch Case Statements: Applicable for only 'int' and 'String' - - String grade = 'A'; + String grade = 'A'; - switch (grade) { + switch (grade) { + case 'A': + print("Excellent grade of A"); + break; - case 'A': - print("Excellent grade of A"); - break; + case 'B': + print("Very Good !"); + break; - case 'B': - print("Very Good !"); - break; + case 'C': + print("Good enough. But work hard"); + break; - case 'C': - print("Good enough. But work hard"); - break; + case 'F': + print("You have failed"); + break; - case 'F': - print("You have failed"); - break; - default: - print("Invalid Grade"); - } + default: + print("Invalid Grade"); + } } diff --git a/08_for_loop.dart b/08_for_loop.dart index 01e767a..78af10e 100644 --- a/08_for_loop.dart +++ b/08_for_loop.dart @@ -1,22 +1,20 @@ - void main() { + // FOR Loop - // FOR Loop - - // WAP to find the even numbers between 1 to 10 - - for (int i = 1; i <= 10; i++) { - - if ( i % 2 == 0) { - print(i); - } - } + // WAP to find the even numbers between 1 to 10 + for (int i = 1; i <= 10; i++) { + if (i % 2 == 0) { + print(i.toString() + ' par'); + } else { + print(i.toString() + ' impar'); + } + } - // for ..in loop - List planetList = ["Mercury", "Venus", "Earth", "Mars"]; + // for ..in loop + List planetList = ["Mercury", "Venus", "Earth", "Mars"]; - for (String planet in planetList) { - print(planet); - } + for (String planet in planetList) { + print(planet); + } } diff --git a/09_while_loop.dart b/09_while_loop.dart index 9f91313..af187af 100644 --- a/09_while_loop.dart +++ b/09_while_loop.dart @@ -1,16 +1,14 @@ - void main() { - - // WHILE Loop - // WAP to find the even numbers between 1 to 10 - - var i = 1; - while (i <= 10) { - - if (i % 2 == 0) { - print(i); - } - - i++; - } + // WHILE Loop + // WAP to find the even numbers between 1 to 10 + + var i = 0; + print('hello ws'); + while (i <= 500) { + print(i); + if (i % 2 == 0) { + print(i); + } + i += 18; + } } diff --git a/11_break_keyword.dart b/11_break_keyword.dart index ab9b16c..a5c5dd9 100644 --- a/11_break_keyword.dart +++ b/11_break_keyword.dart @@ -1,18 +1,17 @@ - void main() { + // BREAK keyword + // Using Labels + // Nested FOR Loop - // BREAK keyword - // Using Labels - // Nested FOR Loop - - myOuterLoop: for (int i = 1; i <= 3; i++) { - - innerLoop: for (int j = 1; j <= 3; j++) { - print("$i $j"); + myOuterLoop: + for (int i = 1; i <= 3; i++) { + for (int j = 1; j <= 3; j++) { + print("$i $j"); - if (i == 2 && j == 2) { - break myOuterLoop; - } - } - } + if (i == 2 && j == 2) { + print('breaking'); + break myOuterLoop; + } + } + } } diff --git a/12_continue_keyword.dart b/12_continue_keyword.dart index 51fda52..a901b13 100644 --- a/12_continue_keyword.dart +++ b/12_continue_keyword.dart @@ -1,17 +1,17 @@ +// ignore_for_file: unused_label void main() { + // CONTINUE keyword + // Using Labels - // CONTINUE keyword - // Using Labels - - myLoop: for (int i = 1; i <= 3; i++) { - - myInnerLoop: for (int j = 1; j <= 3; j++) { - - if (i == 2 && j == 2) { - continue myLoop; - } - print("$i $j"); - } - } + myLoop: + for (int i = 1; i <= 3; i++) { + myInnerLoop: + for (int j = 1; j <= 3; j++) { + if (i == 2 && j == 2) { + continue myLoop; + } + print("$i $j"); + } + } } diff --git a/13_functions.dart b/13_functions.dart index e7c0322..3ebfd0c 100644 --- a/13_functions.dart +++ b/13_functions.dart @@ -1,27 +1,21 @@ - - // OBJECTIVES // 1. Define a Function // 2. Pass parameters to a Function // 3. Return value from a Function // 4. Test that by default a Function returns null -void main() { - - findPerimeter(4, 2); - - int rectArea = getArea(10, 5); - print("The area is $rectArea"); -} - -void findPerimeter(int length, int breadth) { - - int perimeter = 2 * (length + breadth); - print("The perimeter is $perimeter"); +findPerimeter(int length, int breadth) { + int perimeter = 2 * (length + breadth); + print("The perimeter is $perimeter"); } int getArea(int length, int breadth) { + int area = length * breadth; + return area; +} - int area = length * breadth; - return area; +void main() { + findPerimeter(4, 2); + print('o perimetro eh ${findPerimeter(8, 50)}'); + print("The area is ${getArea(10, 5)}"); } diff --git a/14_function_expression.dart b/14_function_expression.dart index 2200ed5..79171aa 100644 --- a/14_function_expression.dart +++ b/14_function_expression.dart @@ -1,14 +1,15 @@ // OBJECTIVE: Expression in Function: SHORT HAND SYNTAX void main() { + findPerimeter(4, 2); - findPerimeter(4, 2); - - int rectArea = getArea(10, 5); - print("The area is $rectArea"); + int rectArea = getArea(10, 5); + print("The area is $rectArea"); + print('the perimeter is ${findPerimeter(5, 5)}'); } -void findPerimeter(int length, int breadth) => print("The perimeter is ${2 * (length + breadth)}"); +findPerimeter(int length, int breadth) => + print("The perimeter is ${2 * (length + breadth)}"); int getArea(int length, int breadth) => length * breadth; diff --git a/15_optional_positional_params.dart b/15_optional_positional_params.dart index 74d81b8..484c374 100644 --- a/15_optional_positional_params.dart +++ b/15_optional_positional_params.dart @@ -1,28 +1,23 @@ - // 1. Required Parameters // 2. Optional Positional Parameters void main() { + printCities("New York", "New Delhi", "Sydney"); + print(""); - printCities("New York", "New Delhi", "Sydney"); - print(""); - - printCountries("USA"); // You can skip the Optional Positional Parameters - + printCountries("USA"); // You can skip the Optional Positional Parameters } // Required Parameters void printCities(String name1, String name2, String name3) { - - print("Name 1 is $name1"); - print("Name 2 is $name2"); - print("Name 3 is $name3"); + print("Name 1 is $name1"); + print("Name 2 is $name2"); + print("Name 3 is $name3"); } // Optional Positional Parameters -void printCountries(String name1, [String name2, String name3]) { - - print("Name 1 is $name1"); - print("Name 2 is $name2"); - print("Name 3 is $name3"); +void printCountries(String name1, [name2, name3]) { + print("Name 1 is $name1"); + print("Name 2 is $name2"); + print("Name 3 is $name3"); } diff --git a/16_named_parameters.dart b/16_named_parameters.dart index 24dd43e..e48b9d5 100644 --- a/16_named_parameters.dart +++ b/16_named_parameters.dart @@ -1,19 +1,17 @@ - // Optional Named Parameters void main() { - findVolume(10, breadth: 5, height: 20); - print(""); + findVolume(10, breadth: 5, height: 20); + print(""); - findVolume(10, height: 20, breadth: 5); // Sequence doesn't matter in Named Parameter + findVolume(10, + height: 20, breadth: 5); // Sequence doesn't matter in Named Parameter } +void findVolume(int length, {breadth, height}) { + print("Length is $length"); + print("Breadth is $breadth"); + print("Height is $height"); -int findVolume(int length, {int breadth, int height}) { - - print("Length is $length"); - print("Breadth is $breadth"); - print("Height is $height"); - - print("Volume is ${length * breadth * height}"); + print("Volume is ${length * breadth * height}"); } diff --git a/17_default_parameters.dart b/17_default_parameters.dart index 122f30c..5cfd467 100644 --- a/17_default_parameters.dart +++ b/17_default_parameters.dart @@ -1,23 +1,22 @@ - // Optional Default Parameters void main() { + findVolume(10); // Default value comes into action + print(""); - findVolume(10); // Default value comes into action - print(""); - - findVolume(10, breadth: 5, height: 30); // Overrides the old value with new one - print(""); + findVolume(10, + breadth: 5, height: 30); // Overrides the old value with new one + print(""); - findVolume(10, height: 30, breadth: 5); // Making use of Named Parameters with Default values + findVolume(10, + height: 30, + breadth: 5); // Making use of Named Parameters with Default values } +void findVolume(int length, {int breadth = 2, int height = 20}) { + print("Lenght is $length"); + print("Breadth is $breadth"); + print("Height is $height"); -int findVolume(int length, {int breadth = 2, int height = 20}) { - - print("Lenght is $length"); - print("Breadth is $breadth"); - print("Height is $height"); - - print("Volume is ${length * breadth * height}"); + print("Volume is ${length * breadth * height}"); } diff --git a/18_exception_handling.dart b/18_exception_handling.dart index 6f3b486..a67afe4 100644 --- a/18_exception_handling.dart +++ b/18_exception_handling.dart @@ -1,4 +1,3 @@ - // OBJECTIVE: Exception Handling // 1. ON Clause // 2. Catch Clause with Exception Object @@ -7,65 +6,68 @@ // 5. Create our own Custom Exception void main() { + print("CASE 1"); + // CASE 1: When you know the exception to be thrown, use ON Clause + try { + int result = 12 ~/ 0; + print("The result is $result"); + } on UnsupportedError { + print("Cannot divide by Zero"); + } - print("CASE 1"); - // CASE 1: When you know the exception to be thrown, use ON Clause - try { - int result = 12 ~/ 0; - print("The result is $result"); - } on IntegerDivisionByZeroException { - print("Cannot divide by Zero"); - } - - print(""); print("CASE 2"); - // CASE 2: When you do not know the exception use CATCH Clause - try { - int result = 12 ~/ 0; - print("The result is $result"); - } catch (e) { - print("The exception thrown is $e"); - } + print(""); + print("CASE 2"); + // CASE 2: When you do not know the exception use CATCH Clause + try { + int result = 12 ~/ 0; + print("The result is $result"); + } catch (e) { + print("The exception thrown is $e"); + } - print(""); print("CASE 3"); - // CASE 3: Using STACK TRACE to know the events occurred before Exception was thrown - try { - int result = 12 ~/ 0; - print("The result is $result"); - } catch (e, s) { - print("The exception thrown is $e"); - print("STACK TRACE \n $s"); - } + print(""); + print("CASE 3"); + // CASE 3: Using STACK TRACE to know the events occurred before Exception was thrown + try { + int result = 12 ~/ 0; + print("The result is $result"); + } catch (e, s) { + print("The exception thrown is $e"); + print("STACK TRACE \n $s"); + } - print(""); print("CASE 4"); - // CASE 4: Whether there is an Exception or not, FINALLY Clause is always Executed - try { - int result = 12 ~/ 3; - print("The result is $result"); - } catch (e) { - print("The exception thrown is $e"); - } finally { - print("This is FINALLY Clause and is always executed."); - } + print(""); + print("CASE 4"); + // CASE 4: Whether there is an Exception or not, FINALLY Clause is always Executed + try { + int result = 12 ~/ 3; + print("The result is $result"); + } catch (e) { + print("The exception thrown is $e"); + } finally { + print("This is FINALLY Clause and is always executed."); + } - print(""); print("CASE 5"); - // CASE 5: Custom Exception - try { - depositMoney(-200); - } catch (e) { - print(e.errorMessage()); - } finally { - // Code - } + print(""); + print("CASE 5"); + // CASE 5: Custom Exception + try { + depositMoney(-200); + } catch (e) { + print(e); + } finally { + // Code + } } class DepositException implements Exception { - String errorMessage() { - return "You cannot enter amount less than 0"; - } + String errorMessage() { + return "You cannot enter amount less than 0"; + } } void depositMoney(int amount) { - if (amount < 0) { - throw new DepositException(); - } + if (amount < 0) { + throw new DepositException(); + } } diff --git a/19_class_and_objects.dart b/19_class_and_objects.dart index 086ccab..ea62865 100644 --- a/19_class_and_objects.dart +++ b/19_class_and_objects.dart @@ -1,31 +1,30 @@ void main() { + var student1 = Student(); // One Object, student1 is reference variable + student1.id = 23; + student1.name = "Peter"; + print("id ${student1.id} linked to student ${student1.name}"); - var student1 = Student(); // One Object, student1 is reference variable - student1.id = 23; - student1.name = "Peter"; - print("${student1.id} and ${student1.name}"); + student1.study(); + student1.sleep(); - student1.study(); - student1.sleep(); - - var student2 = Student(); // One Object, student2 is reference variable - student2.id = 45; - student2.name = "Sam"; - print("${student2.id} and ${student2.name}"); - student2.study(); - student2.sleep(); + var student2 = Student(); // One Object, student2 is reference variable + student2.id = 45; + student2.name = "Sam"; + print("${student2.id} and ${student2.name}"); + student2.study(); + student2.sleep(); } // Define states (properties) and behavior of a Student class Student { - int id = -1; // Instance or Field Variable, default value is -1 - String name; // Instance or Field Variable, default value is null + int? id; // Instance or Field Variable, default value is -1 + String? name; // Instance or Field Variable, default value is null - void study() { - print("${this.name} is now studying"); - } + void study() { + print("${this.name} is now studying"); + } - void sleep() { - print("${this.name} is now sleeping"); - } + void sleep() { + print("${this.name} is now sleeping"); + } } diff --git a/20_constructors.dart b/20_constructors.dart index d39ac4a..111a886 100644 --- a/20_constructors.dart +++ b/20_constructors.dart @@ -1,4 +1,3 @@ - // Objectives // 1. Default Constructor // 2. Parameterized Constructor @@ -6,48 +5,54 @@ // 4. Constant Constructor void main() { + var student1 = + Student(23, "Peter"); // One Object, student1 is reference variable + print("${student1.id} and ${student1.name}"); - var student1 = Student(23, "Peter"); // One Object, student1 is reference variable - print("${student1.id} and ${student1.name}"); - - student1.study(); - student1.sleep(); - - var student2 = Student(45, "Sam"); // One Object, student2 is reference variable - print("${student2.id} and ${student2.name}"); + student1.study(); + student1.sleep(); - student2.study(); - student2.sleep(); + var student2 = + Student(45, "Sam"); // One Object, student2 is reference variable + print("${student2.id} and ${student2.name}"); + student2.study(); + student2.sleep(); - var student3 = Student.myCustomConstructor(); // One object, student3 is a reference variable - student3.id = 54; - student3.name = "Rahul"; - print("${student3.id} and ${student3.name}"); + var student3 = Student + .myCustomConstructor(); // One object, student3 is a reference variable + student3.id = 54; + student3.name = "Rahul"; + print("${student3.id} and ${student3.name}"); + var student4 = Student.myAnotherNamedConstructor(87, "Paul"); + print("${student4.id} and ${student4.name}"); - var student4 = Student.myAnotherNamedConstructor(87, "Paul"); - print("${student4.id} and ${student4.name}"); + var student5 = Student.myCustomConstructor(); + print("${student5.id} and ${student5.name}"); } // Define states (properties) and behavior of a Student class Student { - int id = -1; - String name; + int id = -1; + String? name = 'NonName'; - Student(this.id, this.name); // Parameterised Constructor + Student(this.id, this.name); // Parameterised Constructor - Student.myCustomConstructor() { // Named Constructor - print("This is my custom constructor"); - } + Student.myCustomConstructor() { + // Named Constructor + this.id; + this.name; + print("This is my custom constructor"); + } - Student.myAnotherNamedConstructor(this.id, this.name); // Named Constructor + Student.myAnotherNamedConstructor(this.id, this.name); // Named Constructor - void study() { - print("${this.name} is now studying"); - } + void study() { + print("${this.name} is now studying"); + } - void sleep() { - print("${this.name} is now sleeping"); - } + void sleep() { + print("${this.name} is now sleeping"); + } } diff --git a/21_getters_setters.dart b/21_getters_setters.dart index 1d28de5..6c0864b 100644 --- a/21_getters_setters.dart +++ b/21_getters_setters.dart @@ -1,27 +1,24 @@ - // Objectives // 1. Default Getter and Setter // 2. Custom Getter and Setter // 3. Private Instance Variable void main() { - var student = Student(); - student.name = "Peter"; // Calling default Setter to set value - print(student.name); // Calling default Getter to get value + student.name = "Peter"; // Calling default Setter to set value + print(student.name); // Calling default Getter to get value - student.percentage = 438.0; // Calling Custom Setter to set value - print(student.percentage); // Calling Custom Getter to get value + student.percentage = 438.0; // Calling Custom Setter to set value + print(student.percentage); // Calling Custom Getter to get value } class Student { + String? name; // Instance Variable with default Getter and Setter - String name; // Instance Variable with default Getter and Setter - - double _percent; // Private Instance Variable for its own library + late double _percent; // Private Instance Variable for its own library // Instance variable with Custom Setter - void set percentage(double marksSecured) => _percent = (marksSecured / 500) * 100; + void set percentage(double insertedNumber) => _percent = (insertedNumber * 2); // Instance variable with Custom Getter double get percentage => _percent; } diff --git a/22_inheritance.dart b/22_inheritance.dart index d1ed8f0..73c0b2c 100644 --- a/22_inheritance.dart +++ b/22_inheritance.dart @@ -1,49 +1,48 @@ - // Objectives // 1. Exploring Inheritance void main() { - - var dog = Dog(); - dog.breed = "Labrador"; - dog.color = "Black"; - dog.bark(); - dog.eat(); - - var cat = Cat(); - cat.color = "White"; - cat.age = 6; - cat.eat(); - cat.meow(); - - var animal = Animal(); - animal.color = "brown"; - animal.eat(); + var dog = Dog(); + dog.breed = "Labrador"; + dog.color = "Black"; + dog.bark(); + dog.eat(); + + var cat = Cat(); + cat.color = "White"; + cat.age = 6; + cat.eat(); + cat.meow(); + + var animal = Animal(); + animal.color = "brown"; + animal.eat(); } class Animal { + String? color; - String color; - - void eat() { - print("Eat !"); - } + void eat() { + print("Eat !"); + } } -class Dog extends Animal { // Dog is Child class or sub class, Animal is super or parent class +class Dog extends Animal { + // Dog is Child class or sub class, Animal is super or parent class - String breed; + String? breed; - void bark() { - print("Bark !"); - } + void bark() { + print("Bark !"); + } } -class Cat extends Animal { // Cat is Child class or sub class, Animal is super or parent class +class Cat extends Animal { + // Cat is Child class or sub class, Animal is super or parent class - int age; + int? age = 0; - void meow() { - print("Meow !"); - } + void meow() { + print("Meow !"); + } } diff --git a/23_method_overriding.dart b/23_method_overriding.dart index 99011d6..b5c6beb 100644 --- a/23_method_overriding.dart +++ b/23_method_overriding.dart @@ -1,38 +1,36 @@ - // Objectives // 1. Exploring Method Overriding void main() { - - var dog = Dog(); - dog.eat(); - - print(dog.color); + var dog = Dog('mastiff', 'yellow'); + dog.eat(); + dog.bark(); } class Animal { + String color = "brown"; - String color = "brown"; - - void eat() { - print("Animal is eating !"); - } + void eat() { + print("Animal $color is eating !"); + } } class Dog extends Animal { - - String breed; - - String color = "Black"; // Property Overriding - - void bark() { - print("Bark !"); - } - - // Method Overriding - void eat() { - print("Dog is eating !"); - super.eat(); - print("More food to eat"); - } + String color = "Black"; // Property Overriding + String? breed; + + Dog(this.breed, this.color); // constructor + + void bark() { + print("Bark !"); + } + + // Method Overriding + @override + void eat() { + // overrides Animal 'eat' function + print("Dog breed $breed color $color eating !"); + super.eat(); + print("More food to eat"); + } } diff --git a/24_inheritance_with_constructors.dart b/24_inheritance_with_constructors.dart index deae98a..3481eb1 100644 --- a/24_inheritance_with_constructors.dart +++ b/24_inheritance_with_constructors.dart @@ -1,46 +1,44 @@ - // Objectives // 1. Inheritance with Default Constructor and Parameterised Constructor // 2. Inheritance with Named Constructor -void main() { +// ignore_for_file: unused_local_variable - var dog1 = Dog("Labrador", "Black"); +void main() { + var dog1 = Dog("Labrador", "Black"); - print(""); + print(""); - var dog2 = Dog("Pug", "Brown"); + var dog2 = Dog("Pug", "Brown"); - print(""); + print(""); - var dog3 = Dog.myNamedConstructor("German Shepherd", "Black-Brown"); + var dog3 = Dog.myNamedConstructor("German Shepherd", "Black-Brown"); } class Animal { + String color; - String color; - - Animal(String color) { - this.color = color; - print("Animal class constructor"); - } + Animal(this.color) { + print("Animal class constructor"); + } - Animal.myAnimalNamedConstrctor(String color) { - print("Animal class named constructor"); - } + Animal.myAnimalNamedConstructor(this.color) { + print("Animal class named constructor $color"); + } } class Dog extends Animal { - - String breed; - - Dog(String breed, String color) : super(color) { - this.breed = breed; - print("Dog class constructor"); - } - - Dog.myNamedConstructor(String breed, String color) : super.myAnimalNamedConstrctor(color) { - this.breed = breed; - print("Dog class Named Constructor"); - } + String breed; + + Dog(this.breed, String color) : super(color) { + this.breed = breed; + print("Dog $breed class $color constructor"); + } + + Dog.myNamedConstructor(this.breed, String color) + : super.myAnimalNamedConstructor(color) { + this.breed = breed; + print("Dog $color class $breed Named Constructor"); + } } diff --git a/25_abstract_class_method.dart b/25_abstract_class_method.dart index 181a2f3..3dc406c 100644 --- a/25_abstract_class_method.dart +++ b/25_abstract_class_method.dart @@ -1,43 +1,37 @@ - // Objectives // 1. Abstract Method // 2. Abstract Class void main() { - // var shape = Shape(); // Error. Cannot instantiate Abstract Class - var rectangle = Rectangle(); - rectangle.draw(); + var rectangle = Rectangle(); + rectangle.draw(); - var circle = Circle(); - circle.draw(); + var circle = Circle(); + circle.draw(); } abstract class Shape { + // Define your Instance variable if needed + int x = 0; + int y = 0; - // Define your Instance variable if needed - int x; - int y; - - void draw(); // Abstract Method + void draw(); // Abstract Method - void myNormalFunction() { - // Some code - } + void myNormalFunction() { + // Some code + } } - class Rectangle extends Shape { - - void draw() { - print("Drawing Rectangle....."); - } + void draw() { + print("Drawing Rectangle....."); + } } class Circle extends Shape { - - void draw() { - print("Drawing Circle....."); - } + void draw() { + print("Drawing Circle....."); + } } diff --git a/26_interface.dart b/26_interface.dart index 2a2df42..673284c 100644 --- a/26_interface.dart +++ b/26_interface.dart @@ -1,46 +1,41 @@ - // Objectives // 1. Interface void main() { - - var tv = Television(); - tv.volumeUp(); - tv.volumeDown(); + var tv = Television(); + tv.volumeUp(); + tv.volumeDown(); + tv.justAnotherMethod(); } -class Remote { - - void volumeUp() { - print("______Volume Up from Remote_______"); - } +abstract class Remote { + void volumeUp() { + print("______Volume Up from Remote_______"); + } - void volumeDown() { - print("______Volume Down from Remote_______"); - } + void volumeDown() { + print("______Volume Down from Remote_______"); + } } class AnotherClass { - - void justAnotherMethod(){ - // Code - } - + void justAnotherMethod() { + // Code + } } // Here Remote and AnotherClass acts as Interface class Television implements Remote, AnotherClass { - - void volumeUp() { + void volumeUp() { // super.volumeUp(); // Not allowed to call super while implementing a class as Interface - print("______Volume Up in Television_______"); - } + print("______Volume Up in Television_______"); + } - void volumeDown() { - print("______Volume Down in Television_______"); - } + void volumeDown() { + print("______Volume Down in Television_______"); + } - void justAnotherMethod() { - print("Some code"); - } + void justAnotherMethod() { + print("Some code"); + } } diff --git a/27_static_method_variable.dart b/27_static_method_variable.dart index 0d3f2ce..b856c1b 100644 --- a/27_static_method_variable.dart +++ b/27_static_method_variable.dart @@ -1,20 +1,19 @@ - // Objectives // 1. Static Methods and Variables -void main() { +// ignore_for_file: unused_local_variable - var circle1 = Circle(); +void main() { + var circle1 = Circle(); // circle1.pi; // 4 bytes - var circle2 = Circle(); + var circle2 = Circle(); // circle2.pi; // 4 bytes - // 8 bytes // waste of extra 4 bytes - - Circle.pi; // 4 bytes - Circle.pi; // No more memory will be allocated . + // 8 bytes // waste of extra 4 bytes + Circle.pi; // 4 bytes + Circle.pi; // No more memory will be allocated . // circle.calculateArea(); @@ -24,22 +23,21 @@ void main() { } class Circle { + static const double pi = 3.14; + static int maxRadius = 5; - static const double pi = 3.14; - static int maxRadius = 5; - - String color; + String? color; - static void calculateArea() { - print("Some code to calculate area of Circle"); + static void calculateArea() { + print("Some code to calculate area of Circle"); // myNormalFunction(); // Not allowed to call instance functions // this.color; // You cannot use 'this' keyword and even cannot access Instance variables - } - - void myNormalFunction() { - calculateArea(); - this.color = "Red"; - print(pi); - print(maxRadius); - } + } + + void myNormalFunction() { + calculateArea(); + this.color = "Red"; + print(pi); + print(maxRadius); + } } diff --git a/31_list_fixed_length.dart b/31_list_fixed_length.dart index 3dd9581..b6b5191 100644 --- a/31_list_fixed_length.dart +++ b/31_list_fixed_length.dart @@ -1,40 +1,40 @@ - // Objectives // 1. Fixed-length list void main() { + // Elements: N N N N N + // Index: 0 1 2 3 4 - // Elements: N N N N N - // Index: 0 1 2 3 4 - - List numbersList = List(5); // Fixed-length list - numbersList[0] = 73; // Insert operation - numbersList[1] = 64; - numbersList[3] = 21; - numbersList[4] = 12; + List numbersList = List.empty(); // Fixed-length list + numbersList[0] = 73; // Insert operation + numbersList[1] = 64; + numbersList[3] = 21; + numbersList[4] = 12; - numbersList[0] = 99; // Update operation - numbersList[1] = null;// Delete operation + numbersList[0] = 99; // Update operation + numbersList[1] = null; // Delete operation - print(numbersList[0]); - print("\n"); + print(numbersList[0]); + print("\n"); // numbersList.remove(73); // Not supported in fixed-length list // numbersList.add(24); // Not supported in fixed-length list // numbersList.removeAt(3); // Not supported in fixed-length list // numbersList.clear(); // Not supported in fixed-length list - for (int element in numbersList) { // Using Individual Element (Objects) - print(element); - } + for (int? element in numbersList) { + // Using Individual Element (Objects) + print(element); + } - print("\n"); + print("\n"); - numbersList.forEach((element) => print(element)); // Using Lambda + numbersList.forEach((element) => print(element)); // Using Lambda - print("\n"); + print("\n"); - for (int i = 0; i < numbersList.length; i++) { // Using Index - print(numbersList[i]); - } + for (int i = 0; i < numbersList.length; i++) { + // Using Index + print(numbersList[i]); + } } diff --git a/32_list_growable.dart b/32_list_growable.dart index f52a009..507322a 100644 --- a/32_list_growable.dart +++ b/32_list_growable.dart @@ -1,46 +1,49 @@ - // Objectives // 1. Growable list void main() { - // Elements: N 21 12 - // Index: 0 1 2 - - List countries = ["USA", "INDIA", "CHINA"]; // Growable List : METHOD 1 - countries.add("Nepal"); - countries.add("Japan"); - - - List numbersList = List(); // Growable List: METHOD 2 - numbersList.add(73); // Insert Operation - numbersList.add(64); - numbersList.add(21); - numbersList.add(12); - - numbersList[0] = 99; // Update operation - numbersList[1] = null; // Delete operation - - print(numbersList[0]); - - numbersList.remove(99); - numbersList.add(24); - numbersList.removeAt(3); + // Elements: N 21 12 + // Index: 0 1 2 + + List countries = [ + "USA", + "INDIA", + "CHINA" + ]; // Growable List : METHOD 1 + countries.add("Nepal"); + countries.add("Japan"); + + List numbersList = List.empty(); // Growable List: METHOD 2 + numbersList.add(73); // Insert Operation + numbersList.add(64); + numbersList.add(21); + numbersList.add(12); + + numbersList[0] = 99; // Update operation + numbersList[1] = null; // Delete operation + + print(numbersList[0]); + + numbersList.remove(99); + numbersList.add(24); + numbersList.removeAt(3); // numbersList.clear(); - print("\n"); - - for (int element in numbersList) { // Using Individual Element ( Objects ) - print(element); - } + print("\n"); - print("\n"); + for (int? element in numbersList) { + // Using Individual Element ( Objects ) + print(element); + } - numbersList.forEach((element) => print(element)); // Using Lambda + print("\n"); - print("\n"); + numbersList.forEach((element) => print(element)); // Using Lambda - for (int i = 0; i < numbersList.length; i++) { // Using Index - print(numbersList[i]); - } + print("\n"); + for (int i = 0; i < numbersList.length; i++) { + // Using Index + print(numbersList[i]); + } } diff --git a/33_maps_and_hashmap.dart b/33_maps_and_hashmap.dart index eaf15ba..71272a6 100644 --- a/33_maps_and_hashmap.dart +++ b/33_maps_and_hashmap.dart @@ -1,46 +1,49 @@ - // Objectives // 1. Maps // --> KEY has to be unique // --> VALUE can be duplicate -void main() { - - Map countryDialingCode = { // Method 1: Using Literal - "USA": 1, - "INDIA": 91, - "PAKISTAN": 92 - }; - +// ignore_for_file: unused_local_variable - Map fruits = Map(); // Method 2: Using Constructor - fruits["apple"] = "red"; - fruits["banana"] = "yellow"; - fruits["guava"] = "green"; - - fruits.containsKey("apple"); // returns true if the KEY is present in Map - fruits.update("apple", (value) => "green"); // Update the VALUE for the given KEY - fruits.remove("apple"); // removes KEY and it's VALUE and returns the VALUE - fruits.isEmpty; // returns true if the Map is empty - fruits.length; // returns number of elements in Map +void main() { + Map countryDialingCode = { + // Method 1: Using Literal + "USA": 1, + "INDIA": 91, + "PAKISTAN": 92 + }; + + Map fruits = Map(); // Method 2: Using Constructor + fruits["apple"] = "red"; + fruits["banana"] = "yellow"; + fruits["guava"] = "green"; + + fruits.containsKey("apple"); // returns true if the KEY is present in Map + fruits.update( + "apple", (value) => "green"); // Update the VALUE for the given KEY + fruits.remove("apple"); // removes KEY and it's VALUE and returns the VALUE + fruits.isEmpty; // returns true if the Map is empty + fruits.length; // returns number of elements in Map // fruits.clear(); // Deletes all elements - print(fruits["apple"]); - - print("\n"); + print(fruits["apple"]); - for (String key in fruits.keys) { // Print all keys - print(key); - } + print("\n"); - print("\n"); + for (String key in fruits.keys) { + // Print all keys + print(key); + } - for (String value in fruits.values) { // Print all values - print(value); - } + print("\n"); - print("\n"); + for (String value in fruits.values) { + // Print all values + print(value); + } - fruits.forEach((key, value) => print("key: $key and value: $value")); // Using Lambda + print("\n"); + fruits.forEach( + (key, value) => print("key: $key and value: $value")); // Using Lambda }