Graphics2D Uhr refreshen

p4ul · 25. Jun 2012

Hallo,
ich habe mir mit Graphics eine Digital Uhr gezeichnet, die secunden Ticken auch, aber jetzt spielt meine Oberfläche total verrückt, und ich bekomme eine Fehlermeldung.

Solange ich mit einem anderen Panel über die Uhr Wische siehts noch Ok aus. XD
lg Paul

Java:

import java.awt.AlphaComposite;
import java.awt.BasicStroke;
import java.awt.Color;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.RenderingHints;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.util.GregorianCalendar;
import javax.swing.Timer;

import javax.swing.JPanel;

public class DateTime
extends JPanel 
{
	private int sizex = 150;
	private int sizey = 50;
	
	private int locationx = 800;
	private int locationy = 500;
	

	private String sday;
	private String shour;
	private String sminute;
	private String ssecond;
	
	private int day;
	private int hour;
	private int minute;
	private int second;
	
	private GregorianCalendar calendar;
	
	private Timer timer;
	
	private Graphics2D g2;
	
	public DateTime()
	{
		calendar = new GregorianCalendar();
		
		day = calendar.get(calendar.DAY_OF_WEEK);
  		
  		switch(day)
  		{
  		case 0:
  			sday = "sat";
  			break;
  			
  		case 1:
  			sday = "sun";
  			break;
  		
  		case 2:
  			sday = "mon";
  			break;
  			
  		case 3:
  			sday = "tue";
  			break;
  			
  		case 4:
  			sday = "wed";
  			break;
  			
  		case 5:
  			sday = "thu";
  			break;
  			
  		case 6:
  			sday = "fry";
  			break;
  		}
  		
  		hour = calendar.get(calendar.HOUR_OF_DAY);
  		minute = calendar.get(calendar.MINUTE);
  		second = calendar.get(calendar.SECOND);
  		
		
		int delay = 1000;
		ActionListener taskPerformer = new ActionListener() {
				public void actionPerformed(ActionEvent evt) {
					
					second++;
					ssecond = new Integer(second).toString();
					shour = new Integer(hour).toString();
					sminute = new Integer(minute).toString();	
			  		
			  		repaint();
				}
			};
		timer = new Timer(delay, taskPerformer);
		timer.start();

		setSize(sizex, sizey);
		setLocation(locationx, locationy);
		
		setOpaque(true);
		setBackground(new Color(0,0,0,0));
		
		setVisible(true);
		
	}
	


	public void paintComponent(Graphics g) {
        
		g2 = (Graphics2D)g;
	    RenderingHints rh = new RenderingHints(
	             RenderingHints.KEY_ANTIALIASING,
	             RenderingHints.VALUE_ANTIALIAS_ON);
	    g2.setRenderingHints(rh);

	    final BasicStroke dashed = new BasicStroke(2);
	    g2.setStroke(dashed);
	    
	    super.paintComponent(g2);
	   
        g2.setColor(new Color(20,20,90));
        g2.drawRoundRect(3, 3, getWidth()-6, getHeight()-6, 15, 15);
        
        g2.setColor(new Color(250,180,180));       
        g2.setComposite(AlphaComposite.getInstance(
                AlphaComposite.SRC_OVER, .4f));
        g2.fillRoundRect(3, 3, getWidth()-7, getHeight()-7, 15, 15);
        g2.setComposite(AlphaComposite.getInstance(
                AlphaComposite.SRC_OVER, .9F));
        g2.setColor(new Color(0,0,0));
        
        g2.drawString(sday, 8, 17);
		g2.drawString(shour, 35, 17);
		g2.drawString(sminute, 55, 17);
		g2.drawString(ssecond, 75, 17);
		
		

    }
}

Java:

Exception in thread "AWT-EventQueue-0" java.lang.NullPointerException: String is null
	at sun.java2d.SunGraphics2D.drawString(SunGraphics2D.java:2795)
	at DateTime.paintComponent(DateTime.java:134)
	at javax.swing.JComponent.paint(JComponent.java:1054)
	at javax.swing.JComponent.paintToOffscreen(JComponent.java:5221)
	at javax.swing.RepaintManager$PaintManager.paintDoubleBuffered(RepaintManager.java:1482)
	at javax.swing.RepaintManager$PaintManager.paint(RepaintManager.java:1413)
	at javax.swing.RepaintManager.paint(RepaintManager.java:1206)
	at javax.swing.JComponent._paintImmediately(JComponent.java:5169)
	at javax.swing.JComponent.paintImmediately(JComponent.java:4980)
	at javax.swing.RepaintManager.paintDirtyRegions(RepaintManager.java:770)
	at javax.swing.RepaintManager.paintDirtyRegions(RepaintManager.java:728)
	at javax.swing.RepaintManager.prePaintDirtyRegions(RepaintManager.java:677)
	at javax.swing.RepaintManager.access$700(RepaintManager.java:59)
	at javax.swing.RepaintManager$ProcessingRunnable.run(RepaintManager.java:1621)
	at java.awt.event.InvocationEvent.dispatch(InvocationEvent.java:251)
	at java.awt.EventQueue.dispatchEventImpl(EventQueue.java:705)
	at java.awt.EventQueue.access$000(EventQueue.java:101)
	at java.awt.EventQueue$3.run(EventQueue.java:666)
	at java.awt.EventQueue$3.run(EventQueue.java:664)
	at java.security.AccessController.doPrivileged(Native Method)
	at java.security.ProtectionDomain$1.doIntersectionPrivilege(ProtectionDomain.java:76)
	at java.awt.EventQueue.dispatchEvent(EventQueue.java:675)
	at java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:211)
	at java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:128)
	at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:117)
	at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:113)
	at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:105)
	at java.awt.EventDispatchThread.run(EventDispatchThread.java:90)
Exception in thread "AWT-EventQueue-0" java.lang.NullPointerException: String is null
	at sun.java2d.SunGraphics2D.drawString(SunGraphics2D.java:2795)
	at DateTime.paintComponent(DateTime.java:134)
	at javax.swing.JComponent.paint(JComponent.java:1054)
	at javax.swing.JComponent.paintChildren(JComponent.java:887)
	at javax.swing.JComponent.paint(JComponent.java:1063)
	at javax.swing.JLayeredPane.paint(JLayeredPane.java:585)
	at javax.swing.JComponent.paintChildren(JComponent.java:887)
	at javax.swing.JComponent.paint(JComponent.java:1063)
	at javax.swing.JLayeredPane.paint(JLayeredPane.java:585)
	at javax.swing.JComponent.paintChildren(JComponent.java:887)
	at javax.swing.JComponent.paint(JComponent.java:1063)
	at javax.swing.JComponent.paintToOffscreen(JComponent.java:5221)
	at javax.swing.RepaintManager$PaintManager.paintDoubleBuffered(RepaintManager.java:1482)
	at javax.swing.RepaintManager$PaintManager.paint(RepaintManager.java:1413)
	at javax.swing.RepaintManager.paint(RepaintManager.java:1206)
	at javax.swing.JComponent._paintImmediately(JComponent.java:5169)
	at javax.swing.JComponent.paintImmediately(JComponent.java:4980)
	at javax.swing.RepaintManager.paintDirtyRegions(RepaintManager.java:770)
	at javax.swing.RepaintManager.paintDirtyRegions(RepaintManager.java:728)
	at javax.swing.RepaintManager.prePaintDirtyRegions(RepaintManager.java:677)
	at javax.swing.RepaintManager.access$700(RepaintManager.java:59)
	at javax.swing.RepaintManager$ProcessingRunnable.run(RepaintManager.java:1621)
	at java.awt.event.InvocationEvent.dispatch(InvocationEvent.java:251)
	at java.awt.EventQueue.dispatchEventImpl(EventQueue.java:705)
	at java.awt.EventQueue.access$000(EventQueue.java:101)
	at java.awt.EventQueue$3.run(EventQueue.java:666)
	at java.awt.EventQueue$3.run(EventQueue.java:664)
	at java.security.AccessController.doPrivileged(Native Method)
	at java.security.ProtectionDomain$1.doIntersectionPrivilege(ProtectionDomain.java:76)
	at java.awt.EventQueue.dispatchEvent(EventQueue.java:675)
	at java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:211)
	at java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:128)
	at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:117)
	at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:113)
	at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:105)
	at java.awt.EventDispatchThread.run(EventDispatchThread.java:90)

Marco13 · 25. Jun 2012

Wenn er eine NullPointerException wirft, wo er bei "Graphics2D.drawString" sagt: String is null, dann liegt das wohl daran, dass bei Graphics2D.drawString ein String übergeben wurde, der null ist.

Mit
private String sday = "";
private String shour = "";
private String sminute = "";
private String ssecond = "";
sind die zu zeichnenden Strings am Anfang NICHT null, dann sollte da auch nichts mehr fliegen....

p4ul · 25. Jun 2012

Vielen Dank ,
es hat zusammen mit "setOpaque(false)" jetzt endlich funktioniert.

Java:

import java.awt.AlphaComposite;
import java.awt.BasicStroke;
import java.awt.Color;
import java.awt.Dimension;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.RenderingHints;
import java.awt.Toolkit;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.util.GregorianCalendar;
import javax.swing.Timer;

import javax.swing.JPanel;

public class MyClock
extends JPanel implements ActionListener
{
	private int sizex = 150;
	private int sizey = 50;
	
	private Dimension screensize = Toolkit.getDefaultToolkit().getScreenSize();

	private String sday = "";
	private String shour = "";
	private String sminute = "";
	private String ssecond = "";
	
	private int day;
	private int hour;
	private int minute;
	private int second;
	
	private GregorianCalendar calendar;
	
	private Timer timer;
	
	private Graphics2D g2;
	
	public MyClock()
	{
		
		int delay = 1000;
		timer = new Timer(delay, this);
		timer.start();
		
		int locationx = new Integer((int) (screensize.getWidth()-screensize.getWidth()));
		int locationy = new Integer((int) (screensize.getHeight()-sizey));

		setSize(sizex, sizey);
		setLocation(locationx, locationy);
		
		setOpaque(false);
		setBackground(new Color(0,0,0,0));
		
		setVisible(true);
		
	}

	public void paintComponent(Graphics g) {
        
		g2 = (Graphics2D)g;
	    RenderingHints rh = new RenderingHints(
	             RenderingHints.KEY_ANTIALIASING,
	             RenderingHints.VALUE_ANTIALIAS_ON);
	    g2.setRenderingHints(rh);

	    final BasicStroke dashed = new BasicStroke(2);
	    g2.setStroke(dashed);
	    
	    super.paintComponent(g2);
	   
        g2.setColor(new Color(20,20,90));
        g2.drawRoundRect(3, 3, getWidth()-6, getHeight()-6, 15, 15);
        
        g2.setColor(new Color(250,180,180));       
        g2.setComposite(AlphaComposite.getInstance(
                AlphaComposite.SRC_OVER, .4f));
        g2.fillRoundRect(3, 3, getWidth()-7, getHeight()-7, 15, 15);
        g2.setComposite(AlphaComposite.getInstance(
                AlphaComposite.SRC_OVER, .9F));
        g2.setColor(new Color(0,0,0));
        
        g2.drawString(sday, 8, 17);
		g2.drawString(shour, 35, 17);
		g2.drawString(sminute, 55, 17);
		g2.drawString(ssecond, 75, 17);

    }

	@Override
	public void actionPerformed(ActionEvent e) {
		
		calendar = new GregorianCalendar();
		
		day = calendar.get(calendar.DAY_OF_WEEK);
  		
  		switch(day)
  		{
  		case 0:
  			sday = "sat";
  			break;
  			
  		case 1:
  			sday = "sun";
  			break;
  		
  		case 2:
  			sday = "mon";
  			break;
  			
  		case 3:
  			sday = "tue";
  			break;
  			
  		case 4:
  			sday = "wed";
  			break;
  			
  		case 5:
  			sday = "thu";
  			break;
  			
  		case 6:
  			sday = "fry";
  			break;
  		}
  		
  		hour = calendar.get(calendar.HOUR_OF_DAY);
  		minute = calendar.get(calendar.MINUTE);
  		second = calendar.get(calendar.SECOND);
		
		ssecond = new Integer(second).toString();
		shour = new Integer(hour).toString();
		sminute = new Integer(minute).toString();

  		super.repaint();
		
	}
}

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Graphics2D Uhr refreshen

p4ul

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