GUIs Graphical User Interfaces SWING Containers Frame Panel

Τι θα δούμε • Γραφικά περιβάλλοντα GUIs (Graphical User Interfaces) • Βιβλιοθήκη SWING • Containers • Frame • Panel • Components • Label • Button • Text. Field • Layout Managers • Flow. Layout Manager • Border. Layout Manager • Grid. Layout manager

Παράδειγμα JFrame package simple. Frame; import javax. swing. *; public class Simple. Frame extends JFrame { public static void main(String[] args) { JFrame frame = new JFrame ("My First Frame"); frame. set. Bounds(300, 400, 200); frame. set. Default. Close. Operation(JFrame. EXIT_ON_CLOSE); frame. set. Visible(true); } } Output:

Παράδειγμα - JComponent package simple. Frame; import javax. swing. *; public class Simple. Frame extends JFrame { public static void main(String[] args) { JFrame frame = new JFrame ("My First GUI"); frame. set. Size(400, 400); frame. set. Default. Close. Operation(JFrame. EXIT_ON_CLOSE); frame. set. Visible(true); frame. set. Layout(null); JLabel label = new JLabel("JLabel"); JText. Field text = new JText. Field(); JButton button = new JButton("OK"); label. set. Bounds(10, 100, 20); text. set. Bounds(100, 20); button. set. Bounds(100, 50, 60, 20); frame. add(label); frame. add(text); frame. add(button); } } Output:

Swing Components

Παράδειγμα Flow. Layout package example. Flow. Layout; import java. awt. Flow. Layout; Output: import javax. swing. JButton; import javax. swing. JFrame; public class Example. Flow. Layout { public static void main(String[] args) { JFrame win = new JFrame("My First GUI Program"); win. get. Content. Pane(). set. Layout(new Flow. Layout()); for(int i=0; i<10; i++) win. get. Content. Pane(). add(new JButton(String. value. Of(i))); win. pack(); win. set. Visible(true); } } Μικραίνοντας το μήκος και μεγαλώνοντας το πλάτος του παραθύρου:

Παράδειγμα Grid. Layout import javax. swing. *; import java. awt. Grid. Layout; public class Grid. Example extends JFrame { public static void main(String[] args) { JFrame frame = new JFrame JButton b 11 = new JButton b 12 = new JButton b 13 = new JButton b 21 = new JButton b 22 = new JButton b 23 = new JButton ("Grid. Layout Example"); ("Cell 1 1"); ("Cell 1 2"); ("Cell 1 3"); ("Cell 2 1"); ("Cell 2 2"); ("Cell 2 3"); frame. set. Bounds(300, 270, 100); frame. set. Default. Close. Operation(JFrame. EXIT_ON_CLOSE); Grid. Layout grid = new Grid. Layout(2, 3, 5, 5); frame. set. Layout(grid); frame. add(b 11); frame. add(b 12); frame. add(b 13); frame. add(b 21); frame. add(b 22); frame. add(b 23); frame. set. Visible(true); } } Output:

Παράδειγμα Border. Layout (1) import java. awt. Border. Layout; import java. awt. Container; import javax. swing. *; public class Border. Example { public static void main(String[] args) { JFrame win = new JFrame("Border. Layout Example"); Container content = win. get. Content. Pane(); content. set. Layout(new Border. Layout()); content. add("North", new JButton("North")); content. add("South", new JButton("South")); content. add("East", new JButton("East")); content. add("West", new JButton("West") ); content. add("Center", new JButton("Center")); win. pack(); win. set. Visible(true); } } Output: Χωρίς κενά

Παράδειγμα Border. Layout (2) import javax. swing. *; import java. awt. Border. Layout; public class Border. Example 2 { public static void main(String[] args) { JFrame frame = new JFrame("Border. Layout Example 2"); JButton b. North = new JButton("North"); JButton b. South = new JButton("South"); JButton b. West = new JButton("West"); JButton b. East = new JButton("East"); JButton b. Center = new JButton("Center"); frame. set. Bounds(300, 250, 170); frame. set. Default. Close. Operation(JFrame. EXIT_ON_CLOSE); Border. Layout border = new Border. Layout(5, 5); frame. set. Layout(border); frame. add("North", b. North); frame. add("South", b. South); frame. add("West", b. West); frame. add("East", b. East); frame. add("Center", b. Center); frame. set. Visible(true); } } Output: Με κενά

Χρήση πάνελ για διαχείριση πιο περίπλοκων διατάξεων import import java. awt. Grid. Layout; java. awt. Border. Layout; javax. swing. JFrame; javax. swing. JPanel; javax. swing. JButton; public class Panel. Frame extends JFrame{ private final JPanel button. JPanel; //πάνελ για τα κουμπιά private final JButton[] buttons; import javax. swing. JFrame; public class Panel. Demo extends JFrame{ public static void main(String[] args) { Panel. Frame panel. Frame = new Panel. Frame(); panel. Frame. set. Default. Close. Operation(JFrame. EXIT_ON_CLOSE); panel. Frame. set. Size(450, 200); panel. Frame. set. Visible(true); } //συνάρτηση δημιουργίας χωρίς ορίσματα public Panel. Frame() { super("Panel Demo"); buttons = new JButton[5]; button. JPanel = new JPanel(); button. JPanel. set. Layout(new Grid. Layout(1, buttons. length)); //δημιουργία και προσθήκη κουμπιών for (int count = 0; count < buttons. length; count++) { buttons[count] = new JButton("Button " + (count + 1)); button. JPanel. add(buttons[count]); //προσθήκη κουμπιού στο πάνελ } add(button. JPanel, Border. Layout. SOUTH); //προσθήκη panel στο JFrame }//τέλος κατασκευαστή }//τέλος κλάσης } Output:

Παράδειγμα Παράθυρο διαλόγου import javax. swing. JOption. Pane; public class Name. Dialog { public static void main(String[] args) { // προτροπή χρήστη για όνομα String name = JOption. Pane. show. Input. Dialog("What is your name? "); // Δημιουργία μηνύματος String message = String. format("Welcome, %s, to Java Programming!", name); // εμφανίζει το μήνυμα καλωσορίσματος και το όνομα του χρήστη JOption. Pane. show. Message. Dialog(null, message); } } Output:

Παράδειγμα Menu. Bar import javax. swing. *; public class Menu. Example { JMenu menu, submenu; JMenu. Item item 1, item 2, item 3, item 4, item 5; Menu. Example(){ JFrame frame= new JFrame("Menu and Menu. Item Example"); JMenu. Bar menubar = new JMenu. Bar(); menu = new JMenu("Menu"); submenu = new JMenu("Sub Menu"); item 1 = new JMenu. Item("Item 1"); item 2 = new JMenu. Item("Item 2"); item 3 = new JMenu. Item("Item 3"); item 4 = new JMenu. Item("Item 4"); item 5 = new JMenu. Item("Item 5"); menu. add(item 1); menu. add(item 2); menu. add(item 3); submenu. add(item 4); submenu. add(item 5); menu. add(submenu); menubar. add(menu); frame. set. JMenu. Bar(menubar); frame. set. Size(400, 400); frame. set. Layout(null); frame. set. Visible(true); } public static void main(String[] args) { new Menu. Example(); }} Output:

Παράδειγμα Radio Buttons import javax. swing. *; public class Radio. Button. Example { JFrame frame; Radio. Button. Example(){ frame =new JFrame(); frame. set. Title("JRadio. Button"); JRadio. Button r 1 = new JRadio. Button(“Java"); JRadio. Button r 2 = new JRadio. Button(“Python"); r 1. set. Bounds(75, 50, 100, 30); r 2. set. Bounds(75, 100, 30); Button. Group bg = new Button. Group(); bg. add(r 1); bg. add(r 2); frame. add(r 1); frame. add(r 2); frame. set. Size(300, 300); frame. set. Layout(null); frame. set. Visible(true); } public static void main(String[] args) { new Radio. Button. Example(); } } Output: