Java组件覆盖版本5和版本6之间的差异
在开发了针对Java 5的应用程序后,我最近在6中进行了测试,发现有一个组件问题 在jre5中,屏幕开始变暗,按钮“前台”出现在变暗面板的顶部(如预期)。在jre6中,按钮根本不会出现,但确实会变暗。您可以通过将鼠标移到按钮的位置(强制滚动以重新绘制按钮)来将按钮哄出。我可以稍微重新排列代码,使按钮出现在jre6中,但暗显的面板总是画在按钮的顶部 我认为它在jre5中完全有效,但在网上找不到太多帮助,这更多的是运气,而不是良好的判断。如果你能在这种情况下提供任何帮助,我将不胜感激 我已生成以下代码来显示问题:Java组件覆盖版本5和版本6之间的差异,java,swing,Java,Swing,在开发了针对Java 5的应用程序后,我最近在6中进行了测试,发现有一个组件问题 在jre5中,屏幕开始变暗,按钮“前台”出现在变暗面板的顶部(如预期)。在jre6中,按钮根本不会出现,但确实会变暗。您可以通过将鼠标移到按钮的位置(强制滚动以重新绘制按钮)来将按钮哄出。我可以稍微重新排列代码,使按钮出现在jre6中,但暗显的面板总是画在按钮的顶部 我认为它在jre5中完全有效,但在网上找不到太多帮助,这更多的是运气,而不是良好的判断。如果你能在这种情况下提供任何帮助,我将不胜感激 我已生成以下代
import java.awt.AlphaComposite;
import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.Dimension;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.MouseAdapter;
import java.awt.event.MouseEvent;
import java.awt.event.WindowAdapter;
import java.awt.event.WindowEvent;
import javax.swing.BorderFactory;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.Timer;
@SuppressWarnings( "serial" )
public class TranslucentGlass extends JPanel
{
public static void main( String[] args )
{
// Create a frame
JFrame f = new JFrame();
JPanel mainPanel = new JPanel( new BorderLayout() );
JLabel bgLabel = new JLabel( System.getProperty( "java.version" ) );
mainPanel.add( bgLabel, BorderLayout.SOUTH );
// create a panel for the glasspane
final JPanel glassPane = new JPanel();
glassPane.setLayout( new BorderLayout() );
glassPane.setVisible( false );
glassPane.setOpaque( false );
// create the containing panel for the 'foreground' button
final JPanel largePanel = new JPanel( new BorderLayout() );
largePanel.setOpaque( false );
largePanel.setBorder( BorderFactory.createEmptyBorder( 0, 20, 50, 20 ) );
largePanel.add( new JButton( "Foreground" ), BorderLayout.SOUTH );
// set the glass pane and mainpanel
f.add( mainPanel );
f.setGlassPane( glassPane );
f.setPreferredSize( new Dimension( 250, 250 ) );
f.addWindowListener( new WindowAdapter()
{
@Override
public void windowClosing( WindowEvent e )
{
System.exit( 0 );
}
} );
// an action to show or hide the panel on mouse clicked
f.addMouseListener( new MouseAdapter()
{
boolean panelVisible = false;
@Override
public void mouseClicked( MouseEvent e )
{
if( !panelVisible )
{
glassPane.removeAll();
TranslucentGlass dimmingPanel = new TranslucentGlass( false );
dimmingPanel.add( largePanel );
glassPane.add( dimmingPanel );
dimmingPanel.startTimer();
glassPane.setVisible( true );
panelVisible = true;
}
else
{
glassPane.setVisible( false );
panelVisible = false;
}
}
} );
f.pack();
f.setVisible( true );
}
private Timer timer;
private float opacity = 0;
private long sysTime = System.currentTimeMillis();
private static final int TIMER_INTERVAL = 50; // measured in milliseconds
private static final int TIMER_TOTAL = 750; // measured in milliseconds
private static final Color FADE_COLOUR = Color.RED;
private static final float FINAL_OPACITY = 0.3f;
public TranslucentGlass()
{
this( true );
}
public TranslucentGlass( boolean startTimer )
{
super();
setOpaque( false );
setLayout( new BorderLayout() );
// Create a new timer to change the opacity over time and repaint the panel
timer = new Timer( TIMER_INTERVAL, new ActionListener()
{
public void actionPerformed( ActionEvent e )
{
long newSysTime = System.currentTimeMillis();
opacity += FINAL_OPACITY * ( newSysTime - sysTime ) / TIMER_TOTAL;
sysTime = newSysTime;
validate();
repaint();
if( opacity >= FINAL_OPACITY )
{
timer.stop();
}
}
} );
if( startTimer )
{
timer.start();
}
}
public void startTimer()
{
timer.start();
}
// Override the paintComponent calling paintComponent*s* to ensure the panels contents are painted
@Override
protected void paintComponent( Graphics g )
{
final Graphics2D g2 = ( Graphics2D ) g;
g2.setComposite( AlphaComposite.getInstance( AlphaComposite.SRC_OVER, opacity ) );
g2.setColor( FADE_COLOUR );
g2.fillRect( 0, 0, getWidth(), getHeight() );
g2.dispose();
super.paintComponents( g );
}
}
paintComponent中的第一条语句应为
super.paintComponent(g);
以清除屏幕外位图。否则,您可能会得到意外的结果。在paintComponent函数中创建图形上下文的副本。这将解决问题
public void paintComponent( Graphics g )
{
super.paintComponent( g );
Graphics2D g2 = (Graphics2D) g.create();
...
}
您必须尝试这些代码,然后将它们组合在一起
- 及
- 阅读关于
- 阅读全文,包括评论,可能是一个相互询问的选择
图形2d
会导致问题。删除这一行代码使它变得更好,但并没有完全修复它。创建一个图形的副本并使用该副本似乎可以达到目的。