为什么我的JTable错误地排序整数列? [英] Why does my JTable sort an integer column incorrectly?
问题描述
我有一个使用DefaultTableModel的JTable,我允许在用户点击列标题时进行排序。但是,当用户单击具有integer类型数据的列的标头时,它不会正确排序。看起来它是按String而不是整数类型排序。
I have a JTable that uses a DefaultTableModel and I allow for sorting when the user clicks on the column headers. However, when the user clicks on a header for a column that has data of type integer it does not sort properly. It seems like it is sorting by String instead of an integer type.
这是我的代码中我实际将数据添加到表中的部分:
Here is the part of my code where I actually add the data to the table:
DefaultTableModel aModel = (DefaultTableModel) mainView.logEntryTable.getModel();
ResultSetMetaData rsmd; try {
mainView.logEntriesTableModel.setRowCount(0);
rsmd = rs.getMetaData();
int colNo = rsmd.getColumnCount();
while(rs.next()){
Object[] objects = new Object[colNo];
for(int i=0;i<colNo;i++){
objects[i]=rs.getObject(i+1);
}
aModel.addRow(objects);
count++;
}
mainView.logEntryTable.setModel(aModel);
mainView.logEntryTable.getColumnModel().getColumn(0).setMaxWidth(80);
所以我试图覆盖那个方法并最终得到这个:
So I tried to override that method and ended up with this:
@Override
public Class<?> getColumnClass(int columnIndex){
if( columnIndex == 0){
// Return the column class for the integer column
}else{
// Return the column class like we normally would have if we didn't override this method
}
return null;
}
};
我以前从未覆盖过这个,我不太确定它是什么让我这么做这里。
I've never overridden this before and I'm not quite sure what it is expecting me to do here.
推荐答案
试试这个小例子。
正如Kleopatra所建议的,定义与每个列相关的列类将足以使数据正确排序。
As suggested by Kleopatra, defining a column class relevant for each, will be enough to get the data to be sorted correctly.
import javax.swing.*;
import javax.swing.table.*;
import java.util.Comparator;
class TableSorting {
public static void main(String[] args) {
Object[][] data = {
{new Integer(1), "Don't Let Go", new Integer(179)},
{new Integer(2), "Photograph", new Integer(29)},
{new Integer(3), "Hash Pipe", new Integer(186)},
{new Integer(4), "Island In The Sun", new Integer(200)},
{new Integer(5), "Crab", new Integer(154)},
{new Integer(6), "Knock-Down Drag-Out", new Integer(128)},
{new Integer(7), "Smile", new Integer(158)},
{new Integer(8), "Simple Pages", new Integer(176)},
{new Integer(9), "Glorious Day", new Integer(160)},
{new Integer(10), "O Girlfriend", new Integer(230)}
};
Object[] columns = {"Track #", "Title", "Length"};
DefaultTableModel model = new DefaultTableModel(data,columns) {
@Override
public Class getColumnClass(int column) {
switch (column) {
case 0:
return Integer.class;
case 1:
return String.class;
case 2:
return Integer.class;
default:
return String.class;
}
}
};
JTable table = new JTable(model);
JScrollPane scroll = new JScrollPane(table);
table.setAutoCreateRowSorter(true);
JOptionPane.showMessageDialog(null, scroll);
}
}
原始,使用比较器
Original, using a comparator
import javax.swing.*;
import javax.swing.table.*;
import java.util.Comparator;
class TableSorting {
public static void main(String[] args) {
Object[][] data = {
{new Integer(1), "Don't Let Go", new Integer(179)},
{new Integer(2), "Photograph", new Integer(29)},
{new Integer(3), "Hash Pipe", new Integer(186)},
{new Integer(4), "Island In The Sun", new Integer(200)},
{new Integer(5), "Crab", new Integer(154)},
{new Integer(6), "Knock-Down Drag-Out", new Integer(128)},
{new Integer(7), "Smile", new Integer(158)},
{new Integer(8), "Simple Pages", new Integer(176)},
{new Integer(9), "Glorious Day", new Integer(160)},
{new Integer(10), "O Girlfriend", new Integer(230)}
};
Object[] columns = {"Track #", "Title", "Length"};
JTable table = new JTable(data, columns);
JScrollPane scroll = new JScrollPane(table);
DefaultTableModel model = new DefaultTableModel(data,columns);
TableRowSorter trs = new TableRowSorter(model);
class IntComparator implements Comparator {
public int compare(Object o1, Object o2) {
Integer int1 = (Integer)o1;
Integer int2 = (Integer)o2;
return int1.compareTo(int2);
}
public boolean equals(Object o2) {
return this.equals(o2);
}
}
trs.setComparator(0, new IntComparator());
table.setRowSorter(trs);
scroll = new JScrollPane(table);
table.setAutoCreateRowSorter(false);
JOptionPane.showMessageDialog(null, scroll);
}
}
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