eventos en java

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ActionEvent

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actionPerformed(ActionEvent e) {

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}actionPerformed(ActionEvent e) {

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1import java.awt.*;

2 3public class TestButton {

4 private Frame f;

5 private Button b;

6 7 public TestButton() {

8 f = new Frame("Test");

9 b = new Button("Press Me!");

10

b.setActionCommand("ButtonPressed");

11

}

1213

public void launchFrame() {

14

b.addActionListener(new ButtonHandler());

15

f.add(b,BorderLayout.CENTER);

16

f.pack();

17

f.setVisible(true);

18

}

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public static void main(String args[]) {

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TestButton guiApp = new TestButton();

22

guiApp.launchFrame();

23

}

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}

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1import java.awt.event.*;

2 3publicclass ButtonHandler implements ActionListener {

4 public voidactionPerformed(ActionEvent e) {

5 System.out.println("Action occurred");

6 System.out.println("Button’s command is: "

7 + e.getActionCommand());

8 }

9}

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java.util.EventObject

java.awt.AWTEvent

ActionEvent

AdjustmentEvent

ComponentEvent

TextEvent

ContainerEvent

FocusEvent

InputEvent

WindowEvent

KeyEvent

MouseEvent

java.awt.event

ItemEvent

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Act

ion

ActionListener

actionPerformed(ActionEvent)

Item

ItemListener

itemStateChanged(ItemEvent)

Mo

use

MouseListener

mousePressed(MouseEvent)

mouseReleased(MouseEvent)

mouseEntered(MouseEvent)

mouseExited(MouseEvent)

mouseClicked(MouseEvent)

Mo

use

mo

tio

nMouseMotionListener

mouseDragged(MouseEvent)

mouseMoved(MouseEvent)

Key

KeyListener

keyPressed(KeyEvent)

keyReleased(KeyEvent)

keyTyped(KeyEvent)

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FocusListener

focusGained(FocusEvent)

focusLost(FocusEvent)

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just

men

tAdjustmentListener

adjustmentValueChanged

(AdjustmentEvent)

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mp

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entComponentListener

componentMoved(ComponentEvent)

componentHidden(ComponentEvent)

componentResized(ComponentEvent)

componentShown(ComponentEvent)

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wWindowListener

windowClosing(WindowEvent)

windowOpened(WindowEvent)

windowIconified(WindowEvent)

windowDeiconified(WindowEvent)

windowClosed(WindowEvent)

windowActivated(WindowEvent)

windowDeactivated(WindowEvent)

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nta

iner

ContainerListener

componentAdded(ContainerEvent)

componentRemoved(ContainerEvent)

Tex

tTextListener

textValueChanged(TextEvent)

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1import java.awt.*;


3 4public class TwoListener

5implements MouseMotionListener, MouseListener {

6 private Frame f;

7 private TextField tf;

8 9 public TwoListener() {

10

f = new Frame("Two listeners example");

11

tf = new TextField(30);

12

}

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15

Label label = new Label("Click and drag the mouse");

16

// Add components to the frame

17

f.add(label, BorderLayout.NORTH);

18

f.add(tf, BorderLayout.SOUTH);

19

// Add this object as a listener

20

f.addMouseMotionListener(this);

21

f.addMouseListener(this);

22

// Size the frame and make it visible

23

f.setSize(300, 200);

24

f.setVisible(true);

25

}

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2627

// These are MouseMotionListener events

28

public voidmouseDragged(MouseEvent e) {

29

String s = "Mouse dragging: X = " + e.getX()

30

+ " Y = " + e.getY();

31

tf.setText(s);

32

}

3334

public voidmouseEntered(MouseEvent e) {

35

String s = "The mouse entered";

36

tf.setText(s);

37

}

3839

public voidmouseExited(MouseEvent e) {

40

String s = "The mouse has left the building";

41

tf.setText(s);

42

}

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// Unused MouseMotionListener method.

45

// All methods of a listener must be present in the

46

// class even if they are not used.

47

public void mouseMoved(MouseEvent e) { }

4849

// Unused MouseListener methods.

50

public void mousePressed(MouseEvent e) { }

51

public void mouseClicked(MouseEvent e) { }

52

public void mouseReleased(MouseEvent e) { }

5354


55

TwoListener two = new TwoListener();

56

two.launchFrame();

57

}

58

}

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is:

1import java.awt.*;


3 4public class MouseClickHandler extends MouseAdapter {

5 6 // We just need the mouseClick handler, so we use

7 // an adapter to avoid having to write all the

8 // event handler methods

9 10

public void mouseClicked(MouseEvent e) {

11

// Do stuff with the mouse click...

12

}

13

}

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1import java.awt.*;


3public class TestInner {

4 private Frame f;

5 privateTextField tf; // used by inner class

6 7 public TestInner() {

8 f = new Frame("Inner classes example");

9 tf = new TextField(30);

10

}

1112

classMyMouseMotionListener extends MouseMotionAdapter {

13

public void mouseDragged(MouseEvent e) {

14

String s = "Mouse dragging: X = "+ e.getX()

15

+ " Y = " + e.getY();

16

tf.setText(s);

17

}

18

}

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22


23


24


25

// Add a listener that uses an Inner class

26

f.addMouseMotionListener(new MyMouseMotionListener());

27

f.addMouseListener(new MouseClickHandler());

28


29


30

f.setVisible(true);

31

}

3233


34

TestInner obj = new TestInner();

35

obj.launchFrame();

36

}

37

}

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1import java.awt.*;


3 4public class TestAnonymous {

5 private Frame f;

6 private TextField tf;

7 8 public TestAnonymous() {

9 f = new Frame("Anonymous classes example");

10

tf = new TextField(30);

11

}

1213


14

TestAnonymous obj = new TestAnonymous();

15

obj.launchFrame();

16

}

17

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19


20


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22


23

// Add a listener that uses an anonymous class

24

f.addMouseMotionListener(new MouseMotionAdapter() {

25

public void mouseDragged(MouseEvent e) {

26

String s = "Mouse dragging: X = "+ e.getX()

27

+ " Y = " + e.getY();

28

tf.setText(s);

29

}

30

});// <- note the closing parenthesis

31

f.addMouseListener(new MouseClickHandler()); // Not shown

32


33


34

f.setVisible(true);

35

}

36

}

eventos en java

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