Hello World (1st Version) Mac OS

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Implementing Hello World in Java

  • All code is contained within a class, in this case HelloWorld.
  • The file name must match the class name and have a .java extension, for example: HelloWorld.java
  • All executable statements are contained within a method, in this case named main().
  • Use System.out.println() to print text to the terminal.
  1. Java and the Mac OS X Terminal. 64-bit entry is checked and first in the list; if not, drag to change the preferred order. If all goes well, you should see the output of the program - Hello, World. Input and Output If your program gets stuck in an infinite loop.
  2. Some of the latest Intel based Macs have tha capability to run Mac OS X AND Windows operating systems. If you get a Mac, use OS X Panther (10.3) or Tiger (10.4). OS 10.1 is obsolete. Furthermore, the OS install discs from one model Mac (like the iMac you stated) cannot be used to install the OS on another model Mac.
  3. Some of the latest Intel based Macs have tha capability to run Mac OS X AND Windows operating systems. If you get a Mac, use OS X Panther (10.3) or Tiger (10.4). OS 10.1 is obsolete. Furthermore, the OS install discs from one model Mac (like the iMac you stated) cannot be used to install the OS on another model Mac.

The main field figures out the first page opened by the NW.js if referenced to an HTML file, 'index.html' in this example. And the name field is the unique name used.

Classes and methods (including other flow-control structures) are always defined in blocks of code enclosed by curly braces ({ }).

All other statements are terminated with a semi-colon (;).

https://bestnload309.weebly.com/battle-in-cemetery-mac-os.html. Java language is case-sensitive! This means that HelloWorld is not the same as helloworld, nor is String the same as string.

There is an generally accepted naming convention in the Java community to capitalize the names of Java classes and use the so-called CamelCase (or CamelHump) notation, where the first letter of each word is capitalized, but the words are joined together (i.e. no dashes or underscores).

Note

Java source files can be encoded in UTF-8 to support internationalized characters (even for class, method, and variable names). In most situations however, Java sources are stored in US-ASCII character set, and internationalized strings are loaded from external resource files.

Table 1. Java Keywords

abstract

assert

boolean

break

byte

case

catch

char

class

const

continue

default

do

double

else

enum

extends

final

finally

float

for

goto

if

implements

import

instanceof

int

interface

long

native

new

package

private

protected

public

return

short

static

strictfp

super

switch

synchronized

this

throw

throws

transient

try

void

volatile

while


Hello World (1st Version) Mac Os Download

Keywords goto and const are reserved, but never used.

Keyword strictfp was added in Java 1.2.

Keyword assert was added in Java 1.4.

Keyword enum was added in Java 1.5.

In addition to these 50 keywords, Java also defined three special literals: true, false, and null.

Keywords in our HelloWorld program are in bold:

  • An identifier is the name of a class, variable, field, method, or constructor.

    • Cannot be a Java keyword or a literal
    • Can contain letters, digits, underscores, and dollar signs
    • Cannot start with a digit
  • Valid identifier examples: HelloWorld, args, String, i, Car, $myVar, employeeList2
  • Invalid identifier examples: 1st, byte, my-Arg, *z
  • Java naming conventions for identifiers:

    • Use CamelCase for most identifiers (classes, interfaces, variables, and methods).
    • Use an initial capital letter for classes and interfaces, and a lower case letter for variables and methods.
    • For named constants, use all capital letters separated by underscores.
    • Avoid using $ characters in identifiers.

Identifiers in our HelloWorld program are in bold:

Hello World (1st Version) Mac Os X

  • The JDK comes with a command-line compiler: javac.

    • It compiles source code into Java bytecode, which is low-level instruction set similar to binary machine code.
    • The bytecode is executed by a Java virtual machine (JVM), rather than a specific physical processor.
  • To compile our HelloWorld.java, you could go to the directory containing the source file and execute:

  • This produces the file HelloWorld.class, which contains the Java bytecode.

Hello World (1st Version) Mac Os Pro

Use the javac -help option to get a full list of available options:

You can view the generated byte-code, using the -c option to javap, the Java class disassembler. For example:

Figure 2. Compiling and running a Java program


  • To run the bytecode, execute:

  • Do not include the .class extension.
  • The java command starts the JVM and executes the class bytecode.
  • The JVM abstracts O/S and H/W from the Java application.

It is the Java virtual machine that provides the layer of insulation to Java programs so that they do not depend on the underlying operating system or hardware semantics.

Hello World (1st Version) Mac Os 8

This allows compiled Java applications to run on any platform that has a Java virtual machine written for it:

  • AIX
  • BSD
  • HP-UX
  • Linux
  • Mac OS X
  • Solaris
  • Windows
  • // single-line comment

  • /* Multi-line comment */

    • Useful for commenting out a section of code
    • Cannot be nested within other multi-line comments
  • /** JavaDoc comments */

    • Similar to multi-line comments but used to document Java code (classes, methods, fields)
    • Extracted using javadoc command-line utility
  • A Java application is a public Java class with a main() method.

    • The main() method is the entry point into the application.
    • The signature of the method is always:

    • Command-line arguments are passed through the args parameter, which is an array of Strings

Applets and servlets do not have a main() method because they are run through template methods in the context of a framework. For example, a web container is responsible for instantiating a servlet object. It then invokes a standard set of methods defined by the Servlet class at appropriate points in the servlet lifecycle; for example, init() to initialize the servlet, doGet() to handle an HTTP GET message, destroy() when the web container is about to destroy the object, and so on. The parent class provides default implementations of these methods, but the derived servlet class can override any of the template methods to provide servlet-specific functionality.

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Warning

The iOS Designer was deprecated in Visual Studio 2019 version 16.8 and Visual Studio 2019 for Mac version 8.8, andremoved in Visual Studio 2019 version 16.9 and Visual Studio for Mac version 8.9.The recommended way to build iOS user interfaces is directly on a Mac running Xcode's Interface Builder. For more information, see Designing user interfaces with Xcode.

This guide describes how to create an application that translates an alphanumeric phone number entered by the user into a numeric phone number, and then calls that number. The final application looks like this:

Requirements

iOS development with Xamarin requires:

  • A Mac running macOS High Sierra (10.13) or above.
  • Latest version of Xcode and iOS SDK installed from the App Store .

Xamarin.iOS works with the following setup:

  • Latest version of Visual Studio for Mac that fits the above specifications.

The Xamarin.iOS Mac Installation guide is available for step-by-step installation instructions

Xamarin.iOS works with the following setup:

  • Latest version of Visual Studio 2019 or Visual Studio 2017 Community, Professional, or Enterprise on Windows 10, paired with a Mac build host that fits the above specifications.

The Xamarin.iOS Windows Installation guide is available for step-by-step installation instructions.

Before getting started, download the Xamarin App Icons set.

Visual Studio for Mac Walkthrough

This walkthrough describes how to create an application called Phoneword that translates an alphanumeric phone number into a numeric phone number.

  1. Launch Visual Studio for Mac from the Applications folder or Spotlight:

    On the Launch Screen, click New Project. to create a new Xamarin.iOS solution:

  2. From the New Solution dialog, choose the iOS > App > Single View Application template, ensuring that C# is selected. Click Next:

  3. Configure the app. Give it the NamePhoneword_iOS, and leave everything else as default. Click Next:

  4. Leave the Project and Solution Name as is. Choose the location of the project here, or keep it as the default:

  5. Click Create to make the Solution.

  6. Open the Main.storyboard file by double-clicking on it in the Solution Pad. Ensure you open the file using the Visual Studio iOS Designer (right click the storyboard and select Open With > iOS Designer). This provides a way to visually to create a UI:

    Note that size classes are enabled by default. Refer to the Unified Storyboards guide to learn more about them.

  7. In the Toolbox Pad, type 'label' into the search bar and drag a Label onto the design surface (the area in the center): Vera john slots.

    Note

    You can bring up the Properties Pad or Toolbox at any time by navigating to View > Pads.

  8. Grab the handles of the Dragging Controls (the circles around the control) and make the label wider:

  9. With the Label selected on the design surface, use the Properties Pad to change the Text property of the Label to 'Enter a Phoneword:'

  10. Search for 'text field' inside the Toolbox and drag a Text Field from the Toolbox onto the design surface and place it under the Label. Adjust the width until the Text Field is the same width as the Label:

  11. With the Text Field selected on the design surface, change the Text Field's Name property in the Identity section of the Properties Pad to PhoneNumberText, and change the Text property to '1-855-XAMARIN':

  12. Drag a Button from the Toolbox onto the design surface and place it under the Text Field. Adjust the width so the Button is as wide as the Text Field and Label:

  13. With the Button selected on the design surface, change the Name property in the Identity section of the Properties Pad to TranslateButton. Change the Title property to 'Translate':

  14. Repeat the two steps above and drag a Button from the Toolbox onto the design surface and place it under the first Button. Adjust the width so the Button is as wide as the first Button:

  15. With the second Button selected on the design surface, change the Name property in the Identity section of the Properties Pad to CallButton. Change the Title property to 'Call':

    Save the changes by navigating to File > Save or by pressing ⌘ + s.

  16. Some logic needs to be added to the app to translate phone numbers from alphanumeric to numeric. Add a new file to the Project by right clicking on the Phoneword_iOS Project in the Solution Pad and choosing Add > New File. or pressing ⌘ + n:

  17. In the New File dialog, select General > Empty Class and name the new file PhoneTranslator:

  18. This creates a new, empty C# class for us. Remove all the template code and replace it with the following code:

    Save the PhoneTranslator.cs file and close it.

  19. Add code to wire up the user interface. To do this double-click on ViewController.cs in the Solution Pad to open it:

  20. Begin by wiring up the TranslateButton. In the ViewController class, find the ViewDidLoad method and add the following code beneath the base.ViewDidLoad() call:

    Include using Phoneword_iOS; if the file's namespace is different.

  21. Add code to respond to the user pressing the second button,which is named CallButton. Place the following code below thecode for the TranslateButton and add using Foundation;to the top of the file:

  22. Save the changes and then build the application by choosing Build > Build All or pressing ⌘ + B. If the application compiles, a success message will appear at the top of the IDE:

    If there are errors, go through the previous steps and correct any mistakes until the application builds successfully.

  23. Finally, test the application in the iOS Simulator. In the top left of the IDE, choose Debug from the first dropdown, and iPhone XR iOS 12.0 (or other available simulator) from the second dropdown, and press Start (the triangular button that resembles a Play button):

    Note

    At present, due to a requirement from Apple, it may be necessary to have a development certificate or signing identity to build you code for device or simulator. Follow the steps in the Device Provisioning guide to set this up.

  24. This will launch the application inside the iOS Simulator:

    Phone calls are not supported in the iOS Simulator; instead, you will see an alert dialog when trying to place a call:

Visual Studio Walkthrough

This walkthrough describes how to create an application called Phoneword that translates an alphanumeric phone number into a numeric phone number.

Note

This walkthrough uses Visual Studio Enterprise 2017 on a Windows 10 Virtual Machine. Your set up can differ from this, as long as it meets the requirements above, but be aware that some screenshots may look different to your set up.

Note

Hello World (1st Version) Mac OS

Before proceeding with this walkthrough, you must have already connected to your Mac from Visual Studio. This is because Xamarin.iOS relies on Apple's tooling to build and launch applications. To get set up, follow the steps in the Pair to Mac guide.

  1. Launch Visual Studio from the Start menu:

    Create a new Xamarin.iOS solution by selecting File > New > Project. > Visual C# > iPhone & iPad > iOS App (Xamarin):

    In the next dialog that appears, select the Single View App template and press OK to create the project:

  2. Confirm that the Xamarin Mac Agent icon in the toolbar is green.

    If it isn't, this means that there is no connection to your Mac build host, follow the steps in the configuration guide to get connected.

  3. Open the Main.storyboard file in the iOS Designer by double-clicking on it in the Solution Explorer:

  4. Open the Toolbox tab, type 'label' into the search bar and drag a Label onto the design surface (the area in the center):

  5. Next, grab the handles of the Dragging Controls and make the label wider:

  6. With the Label selected on the design surface, use the Properties Windows to change the Text property of the Label to 'Enter a Phoneword:'

    Note Scp-087-b game (4k) (hdr) mac os.

    You can bring up the Properties or Toolbox at any time by navigating to the View menu.

  7. Search for 'text field' inside the Toolbox and drag a Text Field from the Toolbox onto the design surface and place it under the Label. Adjust the width until the Text Field is the same width as the Label:

  8. With the Text Field selected on the design surface, change the Text Field's Name property in the Identity section of the Properties to PhoneNumberText, and change the Text property to '1-855-XAMARIN':

  9. Drag a Button from the Toolbox onto the design surface and place it under the Text Field. Adjust the width so the Button is as wide as the Text Field and Label:

  10. With the Button selected on the design surface, change the Name property in the Identity section of the Properties to TranslateButton. Change the Title property to 'Translate':

  11. Repeat the previous two steps and drag a Button from the Toolbox onto the design surface and place it under the first Button. Adjust the width so the Button is as wide as the first Button:

  12. With the second Button selected on the design surface, change the Name property in the Identity section of the Properties to CallButton. Change the Title property to 'Call':

    Save the changes by navigating to File > Save All or by pressing Ctrl + s.

  13. Add some code to translate phone numbers from alphanumeric to numeric. To do this, first add a new file to the Project by right-clicking on the Phoneword Project in the Solution Explorer and choosing Add > New Item. or pressing Ctrl + Shift + A:

  14. In the Add New Item dialog (right click on the project, choose Add > New Item.), select Apple > Class and name the new file PhoneTranslator:

    Important

    Make sure that you select the 'class' template that has a C# in the icon. Otherwise you may not be able to reference this new class.

  15. This creates a new C# class. Remove all the template code and replace it with the following code:

    Save the PhoneTranslator.cs https://torrent-school.mystrikingly.com/blog/dungeonscape-mac-os. file and close it.

  16. Double-click on ViewController.cs in the Solution Explorer to open it, so that logic can be added to handles interactions with the buttons:

  17. Begin by wiring up the TranslateButton. In the ViewController class, find the ViewDidLoad method. Add the following button code inside ViewDidLoad, beneath the base.ViewDidLoad() call:

    Include using Phoneword; if the file's namespace is different.

  18. Add code to respond to the user pressing the second button,which is named CallButton. Place the following code below thecode for the TranslateButton and add using Foundation;to the top of the file:

  19. Save the changes, and then build the application by choosing Build > Build Solution or pressing Ctrl + Shift + B. If the application compiles, a success message will appear at the bottom of the IDE:

    If there are errors, go through the previous steps and correct any mistakes until the application builds successfully.

  20. Finally, test the application in the Remoted iOS Simulator. In the IDE toolbar, choose Debug and iPhone 8 Plus iOS x.x from the drop down menus, and press Start (the green triangle that resembles a Play button):

  21. This will launch the application inside the iOS Simulator:

    Phone calls are not supported in the iOS Simulator; instead, an alert dialog will display when trying to place a call:

Congratulations on completing your first Xamarin.iOS application!

Now it's time to dissect the tools and skills shown in this guide in the Hello, iOS Deep Dive.

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