> For the complete documentation index, see [llms.txt](https://htooaunklinn-organization.gitbook.io/htooaunklinn-docs/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://htooaunklinn-organization.gitbook.io/htooaunklinn-docs/hardware-and-iot/java/gui.md).

# GUI

## Introduction

{% code title="Main.java" %}

```java
import javax.swing.JFrame;
import javax.swing.JLabel;

public class Main {
    public static void main(String[] args) {
        JFrame frame = new JFrame();
        frame.setTitle("My Title");
        frame.setResizable(true);
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

        JLabel label = new JLabel("Hello, World!");
        frame.add(label);
        frame.pack();
        frame.setVisible(true);
    }
}
```

{% endcode %}

### Corrected Java Swing Example

The following Java program creates a simple graphical application using Swing. This application displays a window with the title "My Title" and includes a label saying "Hello, World!".

{% code title="Main.java" %}

```java
import javax.swing.JFrame;
import javax.swing.JLabel;

public class Main {
    public static void main(String[] args) {
        JFrame frame = new JFrame();
        frame.setTitle("My Title");
        frame.setSize(500, 500);
        frame.setResizable(true);
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

        JLabel label = new JLabel("Hello, World!");
        frame.add(label);
        frame.setVisible(true);
    }
}
```

{% endcode %}

Key Components:

* **JFrame**: The main window.
* **JLabel**: Displays text within the window.
* **setTitle()**: Sets the window title.
* **setSize()**: Defines the window dimensions.
* **setResizable()**: Allows the window to be resized by the user.
* **setDefaultCloseOperation()**: Determines the close operation of the frame

To set a window's icon in a Java application, first create an `ImageIcon` object with the desired image file and then use the `setIconImage` method:

```java
ImageIcon myLogo = new ImageIcon("filename");
this.setIconImage(myLogo.getImage());
```

Replace `"filename"` with the path to your image file.

## Java GUI Example

This example demonstrates a basic Java GUI application using a custom frame called `MyFrame` which extends `JFrame`.

#### Main.java

```java
public class Main {
    public static void main(String[] args) {
        MyFrame new_frame = new MyFrame();
    }
}
```

#### MyFrame.java

```java
import javax.swing.JFrame;
import javax.swing.JLabel;

public class MyFrame extends JFrame {
    
    MyFrame() {
        this.setTitle("My Title");
        this.setSize(500, 500);
        this.setResizable(true);
        this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

        JLabel label = new JLabel("Hello, World!");
        this.add(label);
        this.setVisible(true);
    }
}
```

Key Components:

* **Title**: Sets the window title to "My Title".
* **Size**: Window dimensions set to 500x500 pixels.
* **Resizable**: Allows users to resize the window.
* **Close Operation**: Exits the application on closing the window.
* **Label**: Displays "Hello, World!" in the window.

Note:

Ensure `javax.swing` is imported for `JFrame` and

The following code snippets demonstrate how to change the background color of a GUI component using Java:

1. Set the background to red:

   ```java
   this.getContentPane().setBackground(Color.RED);
   ```
2. Set the background to green using RGB values:

   ```java
   this.getContentPane().setBackground(new Color(0, 255, 0));
   ```
3. Set the background to white using a hexadecimal value:

   ```java
   this.getContentPane().setBackground(new Color(0xFFFFFF));
   ```

```java
// Creating a label with text
JLabel label = new JLabel("Hello, World!");

// Setting an image icon
ImageIcon img = new ImageIcon("filepath");
label.setIcon(img);

// Configuring text position
label.setHorizontalTextPosition(JLabel.CENTER);
label.setVerticalTextPosition(JLabel.TOP);

// Changing text color
label.setForeground(Color.RED);

// Setting font style and size
label.setFont(new Font("MV Boli", Font.PLAIN, 30));

// Adjusting icon-text gap
label.setIconTextGap(100);

// Aligning label vertically and horizontally
label.setVerticalAlignment(JLabel.CENTER);
label.setHorizontalAlignment(JLabel.CENTER);

// Customizing background and border
label.setBackground(Color.BLUE);
label.setOpaque(true);
Border border = BorderFactory.createLineBorder(Color.GREEN);
label.setBorder(border);
```

In the example code, a component on a frame has its layout set to null, allowing for absolute positioning. The `setBounds` method is missing a component identifier. To correct the code, include the component's name before `setBounds`. For example, if the component is a button, the corrected line would be:

```java
button.setBounds(0, 0, 100, 100);
```

Ensure to replace `button` with the actual component variable name you are using.