清除图像上先前绘制的字符串 [英] Clear previously drawn string over an image
问题描述
我想知道如果我不清除字符串重叠部分，该如何清除之前绘制的字符串，然后再在图像上绘制新的字符串.我已经尝试了graphics#drawRect并覆盖了paintComponent(Graphics)，但仍然没有评估.
I am wondering how I can clear a previously drawn string before drawing a new one over an image, if I do not clear the strings overlap. I have tried graphics#drawRect and overriding paintComponent(Graphics), still no eval.
这是我的代码: paintComponent(Graphics)
Here is my code: paintComponent(Graphics)
public class SplashScreen extends JLabel
{
private static final long serialVersionUID = 5515310205953670741L;
private static final String ROOT = "./assets/img/";
private static final SplashScreen INSTANCE = new SplashScreen( get( new File( ROOT, "splash.png" ) ), get( new File( ROOT, "splash-bar.png" ) ) );
private final BufferedImage background;
private final BufferedImage foreground;
private final JLabel label;
private SplashScreen( BufferedImage background, BufferedImage foreground )
{
this.background = background;
this.foreground = foreground;
label = new JLabel( new ImageIcon( background ) );
JWindow window = new JWindow();
window.setSize( background.getWidth(), background.getHeight() );
window.getContentPane().add( label );
Dimension dimension = Toolkit.getDefaultToolkit().getScreenSize();
window.setLocation( dimension.width / 2 - window.getSize().width / 2, dimension.height / 2 - window.getSize().height / 2 );
window.setVisible( true );
}
public void updateStatus( String status )
{
Graphics g = background.getGraphics();
g.drawString( status, 304, 301 );
g.dispose();
label.repaint();
}
public void updateBar( int width )
{
Graphics g = background.getGraphics();
g.drawImage( foreground, 73, 309, width, foreground.getHeight(), null );
g.dispose();
label.repaint();
}
private static BufferedImage get( File file )
{
try {
return ImageIO.read( file );
} catch( IOException e ) {
throw new RuntimeException( e.getMessage() );
}
}
public static SplashScreen getInstance()
{
return INSTANCE;
}
}
任何帮助将不胜感激. :-)
Any help is greatly appreciated. :-)
谢谢.
推荐答案
您不需要进行自定义绘制.
You don't need to do custom painting.
以下是通过图标将文本绘制在标签上的几种方法:
Here are a couple of different ways to paint text on a label with an Icon:
import java.awt.*;
import javax.swing.*;
import javax.swing.text.*;
public class LabelImageText extends JPanel
{
public LabelImageText()
{
JLabel label1 = new JLabel( new ColorIcon(Color.ORANGE, 100, 100) );
label1.setText( "Easy Way" );
label1.setHorizontalTextPosition(JLabel.CENTER);
label1.setVerticalTextPosition(JLabel.CENTER);
add( label1 );
//
JLabel label2 = new JLabel( new ColorIcon(Color.YELLOW, 200, 150) );
label2.setLayout( new BoxLayout(label2, BoxLayout.Y_AXIS) );
add( label2 );
JLabel text = new JLabel( "More Control" );
text.setAlignmentX(JLabel.CENTER_ALIGNMENT);
label2.add( Box.createVerticalGlue() );
label2.add( text );
label2.add( Box.createVerticalStrut(10) );
//
JLabel label3 = new JLabel( new ColorIcon(Color.GREEN, 200, 150) );
add( label3 );
JLabel text3 = new JLabel();
text3.setText("<html><center>Text<br>over<br>Image<center></html>");
text3.setLocation(20, 20);
text3.setSize(text3.getPreferredSize());
label3.add( text3 );
//
JLabel label4 = new JLabel( new ColorIcon(Color.CYAN, 200, 150) );
add( label4 );
JTextPane textPane = new JTextPane();
textPane.setText("Add some text that will wrap at your preferred width");
textPane.setEditable( false );
textPane.setOpaque(false);
SimpleAttributeSet center = new SimpleAttributeSet();
StyleConstants.setAlignment(center, StyleConstants.ALIGN_CENTER);
StyledDocument doc = textPane.getStyledDocument();
doc.setParagraphAttributes(0, doc.getLength(), center, false);
textPane.setBounds(20, 20, 75, 100);
label4.add( textPane );
}
public static class ColorIcon implements Icon
{
private Color color;
private int width;
private int height;
public ColorIcon(Color color, int width, int height)
{
this.color = color;
this.width = width;
this.height = height;
}
public int getIconWidth()
{
return width;
}
public int getIconHeight()
{
return height;
}
public void paintIcon(Component c, Graphics g, int x, int y)
{
g.setColor(color);
g.fillRect(x, y, width, height);
}
}
private static void createAndShowUI()
{
JFrame frame = new JFrame("LabelImageText");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.add( new LabelImageText() );
frame.pack();
frame.setLocationRelativeTo( null );
frame.setVisible( true );
}
public static void main(String[] args)
{
EventQueue.invokeLater(new Runnable()
{
public void run()
{
createAndShowUI();
}
});
}
}
然后更改文本，只需更改用于显示文本的组件中的文本即可.
Then to change the text you just change the text in the component you are using to display the text.
如果这些方法都不起作用，则进行自定义绘制的方法是重写JLabel的paintCompnent()方法.您不应该直接在BufferedImage上绘制文本.
If none of these help then the way to do custom painting is to override the paintCompnent() method of the JLabel. You should not be painting the text directly on the BufferedImage.
这篇关于清除图像上先前绘制的字符串的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！
