AWT Components
1. What Is AWT? (beginner)
AWT (Abstract Window Toolkit) = Java's first GUI kit (java.awt): windows, buttons, text boxes drawn by OS (native look!). Old but exam-heavy; Swing (later) builds on it!
2. Component Map (exam list!)
import java.awt.*;
Frame f = new Frame("Hi"); // window!
Button b = new Button("Click"); // button!
Label l = new Label("Name:"); // text label!
TextField t = new TextField(20); // one-line input!
TextArea ta = new TextArea(5, 20); // multi-line!
Checkbox c = new Checkbox("veg"); // tick!
Choice ch = new Choice(); ch.add("tea"); // dropdown!
List li = new List(); li.add("a"); // scroll list!
f.add(b); f.add(l); // place (layout decides WHERE — next!)
Hierarchy: Component → Container (holds!) → Frame/Panel/Dialog (windows!).
3. Beginner Full Window (memorize skeleton!)
import java.awt.*;
public class Win {
public static void main(String[] args) {
Frame f = new Frame("My Win");
f.add(new Button("OK"));
f.setSize(300, 200);
f.setLayout(new FlowLayout()); // simple line layout!
f.setVisible(true); // show! (default hidden!)
}
}
4. Traps
setVisible(true)forgotten → invisible window (most common!).setSizeneeded (else 0×0 dot!).- AWT heavyweight (OS peers) vs Swing lightweight (Java-drawn — faster, prettier!).
5. Exam Points
- Component list + window program — 5-7 marks, very frequent.
- Hierarchy +
setVisible/setSize— 3 marks, frequent.