我想知道如何让JOptionPane能够滚动直方图。我设法让JOptionPane显示我的直方图，唯一的问题是你无法滚动它。窗口延伸到屏幕底部，仅显示图形的一半。
注意：只有在读取包含介于0和130之间的300+个整数的大型输入文件时才会发生这种情况。程序将无法识别其他任何内容。
输入值：
54 38 42 40 34 51 54 58 61 55 54 42 40 34 51 54 54 54 38 60 42 40 54 54 54 54 54 54 54 54 54 54 54 54 54 54 54 32 28 24 18 9 4 22 31 38 34 41 32 28 24 18 31 38 34 41 32 28 24 18 31 38 34 41 32 28 31 38 35 51 34 41 56 63 59 66 48 46 58 41 56 63 51 59 48 46 58 41 56 63 53 52 58 48 49 58 41 56 63 51 52 59 58 66 63 71 69 70 72 67 66 63 71 74 75 69 73 78 72 67 63 71 74 59 56 69 70 78 72 66 71 74 69 70 78 72 67 63 59 58 57 64 71 72 67 63 59 64 71 73 79 75 78 72 67 63 59 63 71 73 75 78 72 67 63 57 73 77 75 78 72 67 71 73 77 75 78 81 83 87 84 91 92 90 84 76 83 82 89 78 81 83 87 84 91 92 90 84 78 85 82 89 96 91 78 81 83 86 82 91 92 90 84 85 82 89 92 96 91 95 97 98 91 95 97 93 87 85 94 89 92 96 93 96 97 98 98 100 102 95 97 93 87 88 89 93 84 89 92 95 95 95 97 94 91 87 84 80 90 82 80 73 75 70 74 74 75 70 66 63 71 69 70 72 67 66 63 71 55 59 53 58 52 67 63 71 74 59 56 69 70 58 62 56 51 54 49 60 68 62 67 63 59 58 57 64 44 38 42 40 34 51 54 55 54 42 40 34 51 54 54 54 38 42 31 38 34 41 32 28 24 18 31 38 34 41 32 28 24 18 31 38 34 41 32 28 31 28 35 41 34 37 26 23 29 40 45 46 39 31 40 38 29 34 36
import javax.swing.*;
import java.io.File;
import java.io.FileNotFoundException;
import java.util.Scanner;
import javax.swing.JFileChooser;
import javax.swing.JOptionPane;
public class CoolWeather
{
static JFileChooser selecter;
static Scanner in;
public static void main(String[] args) throws FileNotFoundException
{
//Get Input File
File inputFile;
selecter = new JFileChooser(".");
int status = selecter.showOpenDialog(null);
if(status != JFileChooser.APPROVE_OPTION)
{
JOptionPane.showMessageDialog(null, "Closing Program");
System.exit(0);
}
inputFile = selecter.getSelectedFile();
JOptionPane.showMessageDialog(null, "Opening: " + inputFile.getName());
//Creates Array
int[] temps = readData(inputFile);
//Prints Histogram
showMessage(temps);
}
//The Following Method Creates and Populates An Array With Data
//From The Input File
public static int[] readData(File inputFile) throws FileNotFoundException
{
in = new Scanner(inputFile);
in.useDelimiter("[^0-9/s]+");
int[] temps = new int[131];
int count = 0;
int num;
do
{
num = in.nextInt();
count++;
temps[num]++;
}
while (in.hasNextInt());
JOptionPane.showMessageDialog(null, "The Number Of Entries Read: " + count);
return temps;
}
public static void showMessage(int[] temps)
{
String output = "Temp\tCount\tVisual";
// for each array element, output a bar in histogram
for ( int counter = 0; counter < temps.length; counter++ )
{
if (temps[counter] > 0)
{
output += "\n" + counter + "\t" + temps[ counter ] + "\t";
// print bar of asterisks
for ( int stars = 0; stars < temps[ counter ]; stars++ )
{output += "*";}
}
} // end outer for
JTextArea outputArea = new JTextArea();
outputArea.setText( output );
JOptionPane.showMessageDialog( null, outputArea, "CoolWeather Histogram", JOptionPane.INFORMATION_MESSAGE );
System.exit( 0 );
}
}
答案 0 :(得分：0)
这是我在处理异常时用于UI的JOptionPane，但原则是相同的 - JTextArea中的JScrollPane
JLabel label = new JLabel(e.getLocalizedMessage() + ":");
label.setFont(getFont().deriveFont(Font.BOLD));
label.setAlignmentX(JLabel.LEFT_ALIGNMENT);
StringWriter writer = new StringWriter();
e.printStackTrace(new PrintWriter(writer));
JTextArea textArea = new JTextArea();
textArea.setEditable(false);
textArea.setFont(getFont());
textArea.setTabSize(2);
textArea.setText(writer.toString());
SwingUtilities.invokeLater(() -> textArea.setCaretPosition(0));
JScrollPane scrollPane = new JScrollPane(textArea);
scrollPane.setAlignmentX(JScrollPane.LEFT_ALIGNMENT);
scrollPane.setPreferredSize(new Dimension(500, 200));
JPanel panel = new JPanel();
panel.setLayout(new BoxLayout(panel, BoxLayout.PAGE_AXIS));
panel.add(label);
panel.add(Box.createVerticalStrut(5));
panel.add(scrollPane);
JOptionPane.showMessageDialog(this, panel, ApplicationInfo.getAppName(), JOptionPane.ERROR_MESSAGE);
答案 1 :(得分：0)
JTextArea outputArea = new JTextArea();
outputArea.setText(output);
outputArea.setEditable(false);
JScrollPane scrollPane = new JScrollPane(outputArea);
scrollPane.setAlignmentX(JScrollPane.LEFT_ALIGNMENT);
scrollPane.setPreferredSize(new Dimension(500, 200));
JOptionPane.showMessageDialog( null, scrollPane, "CoolWeather Histogram", JOptionPane.INFORMATION_MESSAGE);
System.exit( 0 );