Java 17 for Absolute Beginners: A Complete Guide to Get Started with Java Programming

Want to start learning Java programming ? This guide is just for you. We’ll cover the basics of Java 17 in simple language— no experience needed! ✅ What You’ll Learn: What is Java? Java 17 Features ( for beginners) Basic Syntax Data Types Operators Conditionals Loops Functions ( Methods) Object- Oriented Programming ( OOP) New Java 17 features ( Text blocks, Records) Practice Program 📌 What is Java? Java is: ✅ A popular and easy- to- learn language ✅ Platform- independent ( write once, run anywhere) ✅ Object- oriented ( based on real- world objects) ✅ Used for apps, websites, games, and more Java 17 is the latest Long- Term Support ( LTS) version, released in 2021. 1. Java 17 Basic Syntax Every Java program has a class and a main() method. public class HelloJava {     public static void main(String[] args) {         System.out.println("Hello, Java 17!");     } } 🔹 Notes: public cla...

How to Enable/Disable Button on Validation using DelegateCommand of Prism


 MainWindow.xaml

 <Window x:Class="Wpf.Views.MainWindow"
             xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
             xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
             xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
             xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
             xmlns:local="clr-namespace:Wpf"
             mc:Ignorable="d">
     <Window.Resources>
         <ControlTemplate  x:Key="TextBoxErrorStyle">
             <StackPanel Orientation="Horizontal">
                 <AdornedElementPlaceholder x:Name="ErrorHolder" >
                     <Border BorderBrush="red" BorderThickness="1" />
                 </AdornedElementPlaceholder>
                 <TextBlock  Text="{Binding [0].ErrorContent}" VerticalAlignment="Center" HorizontalAlignment="Right" Foreground="Red"/>

             </StackPanel>
         </ControlTemplate>

     </Window.Resources>
     <StackPanel Orientation="Vertical" HorizontalAlignment="Left" >
         <TextBox Height="30" Width="200" Text="{Binding Text,Mode=TwoWay,NotifyOnValidationError=True,
                  ValidatesOnDataErrors=True,UpdateSourceTrigger=PropertyChanged}"
                  Validation.ErrorTemplate="{StaticResource TextBoxErrorStyle}" Margin="5" />
         <Button Content="Click Here" Command="{Binding ClickCommand}" Margin="10" Width="100"/>
     </StackPanel>
 </Window>


 MainWindow.xaml.cs

 public partial class MainWindow : Window
     {
       
         public MainWindow()
         {
             InitializeComponent();
             DataContext= new MainWindowViewModel();
         
         }
       
     }

MainWindowViewModel.cs


 using Prism.Commands;
 using Prism.Mvvm;

 public class MainWindowViewModel : BindableBase, IDataErrorInfo
     {
         private string _text = string.Empty;

         public string Text
         {
             get
             {
                 return _text;
             }
             set
             {
                 SetProperty(ref _text, value);
                 ClickCommand.RaiseCanExecuteChanged();

             }
         }
       
         public string Error => string.Empty;

         public string this[string columnName]
         {
             get
             {

                 if (columnName == "Text")
                 {
                     if (string.IsNullOrEmpty(Text?.Trim()))
                         return "Text should not be empty";
                 }
                 return string.Empty;
             }

         }
       
         private DelegateCommand _clickCommand;
       
         public DelegateCommand ClickCommand
         {
             get
             {
                 return _clickCommand = _clickCommand ?? new DelegateCommand(Click, () => !string.IsNullOrEmpty(_text));
             }

         }
       
         private void Click()
         {
             //code
         }
     }

Comments

Popular posts from this blog

Filter DataGrid and ListView in wpf using ICollectionView

Pagination of DataGrid in WPF using MVVM

How to Create TabControl using Prism Region