Controale Java - butoane

  • Elemente de tip "Button"

        Aproape nu exista aplicatie in care sa nu fie necesar cel putin un buton. Urmatoarea aplicatie plaseaza un buton care are rolul de a modifica o eticheta. Textul din eticheta va fi schimbat la apasarea butonului.

        In cazul ca nu se lanseaza aplicatia de sus, pe calculatorul d-voastra trebuie instalat pachetul JDC versiunea JDK6 sau mai recenta.

        Cum se plaseaza elementele de tip button intr-un applet ?
    package Controale;
    
    import java.awt.BorderLayout;
    import java.awt.Rectangle;
    import java.awt.GridBagLayout;
    import javax.swing.JPanel;
    import javax.swing.JApplet;
    import javax.swing.JButton;
    import javax.swing.JLabel;
    
    public class utiliz_buton_v2 extends JApplet {
    
    	private static final long serialVersionUID = 1L;
    	private JPanel c_panel_1 = null; 	// panel_1 cu controale plasate
    	private JPanel panel_1 = null; 		// panoul 1
    	private JLabel etich_1 = null; 		// eticheta 1
    	private JButton but_1 = null; 		// butonul 1
    
    	/**
    	 * Constructorul implicit pentru "utiliz_buton_v2"
    	 */
    	
    	public utiliz_buton_v2() {
    		super();
    	}
    	
    	/**
    	 * Aceasta metoda initializeaza: this
    	 * 
    	 * @returneaza  void
    	 */
    	
    	public void init() {
    		this.setSize(300, 200);
    		this.setContentPane(init_panel_1());
    	}
    
    	/**
    	 * 
    	 * Aceasta metoda creaza butonul: "but_1"	
    	 * Returneaza but_1 de tipul:	javax.swing.JButton
    	 */
    	
    	private JButton creaza_but_1() {
    		if (but_1 == null) {
    			but_1 = new JButton();
    			but_1.setBounds(new Rectangle(100, 140, 70, 30));
    			but_1.setText("Start");
    			but_1.addActionListener(new java.awt.event.ActionListener() {
    				public void actionPerformed(java.awt.event.ActionEvent e) {
    					etich_1.setText("Ati apasat butonul start.");				
    				}
    			});
    		}
    		return but_1;
    	}
    
    	/**
    	 * This method initializes jPanel	
    	 * 	
    	 * @return javax.swing.JPanel	
    	 */
    	
    	private JPanel creaza_panel_1() {
    		if (panel_1 == null) {
    			panel_1 = new JPanel();
    			panel_1.setLayout(new GridBagLayout());
    			panel_1.setBounds(new Rectangle(0, 20, 450, 200));
    		}
    		return panel_1;
    	}
    
    	/**
    	 * Aceasta metoda initializeaza panel_1 plasand controalele dorite 
    	 * Returneaza c_panel_1 de tipul: javax.swing.JPanel 
    	 */
    	
    	private JPanel init_panel_1() {
    		if (c_panel_1 == null) {
    			
    			etich_1 = new JLabel();
    			etich_1.setBounds(new Rectangle(10, 10, 500, 10));
    			etich_1.setText("Apasati butonul -Start-");
    			c_panel_1 = new JPanel();
    			c_panel_1.setLayout(null);
    			c_panel_1.add(creaza_but_1(), null);
    			c_panel_1.add(etich_1, null);
    			c_panel_1.add(creaza_panel_1(), null);
    			c_panel_1.setLayout(new BorderLayout());
    		}
    		return c_panel_1;
    	}
    }