如何将JTable列设置为String并排序为Double? [英] How to set a JTable column as String and sort as Double?
问题描述
我还是Java的新手,对JTable(更具体地说是JXTable)有疑问,并按列类对混合数据类型进行排序......让我详细说明......
I'm still fairly new to Java and have a question in regards to JTable (more specifically JXTable) and sorting rows by column class with mixed data type... Let me elaborate...
我有一个JXTable,用于保存产品列表的数据。这个表有一个价格列,我只设置为String.class,这样我就可以显示前缀为'$'的价格。
I have a JXTable that holds data for a product listing. This table has a column for price which I have set to String.class only so that I can display a price with a '$' prepended.
问题我是如果行按价格排序,它们不会被排序为双打,而是按字符串排序,因此这些值:
The problem I'm having is when the rows are sorted by price, they are not sorted as Doubles, but rather they are sorted as strings so these values:
89.85,179.70,299.40,478.80
89.85, 179.70, 299.40, 478.80
分类为:
179.70,299.40,478.80,89.85(升序)
和
89.85,478.80,299.40,179.70(降序)
179.70, 299.40, 478.80, 89.85 (Ascending) and 89.85, 478.80, 299.40, 179.70 (Descending)
我想要做的是在排序时删除'$'并将列排序为双打。我怎么做到这一点?
What I would like to do is remove the '$' at the time of sorting and sort the column as Doubles. How would I accomplish this?
编辑:
非常感谢Jiri Patera的回复。帮助我理解tablecellrenderer负责在这些类型的情况下操纵值,这是一个很大的帮助。下面是最终完成了我想要的摘录。
Thank you very much Jiri Patera for your response. It was a great help in helping me to understand that the tablecellrenderer is responsible for manipulating values in these types of situations. Below is the finished excerpt that has finally accomplished what I want.
public Component getTableCellRendererComponent(JTable pTable, Object pValue, boolean pIsSelected, boolean pHasFocus, int pRow, int pColumn) {
// Use the wrapped renderer
Component renderedComponent = mWrappedRenderer.getTableCellRendererComponent(pTable, pValue, pIsSelected, pHasFocus, pRow, pColumn);
Component renderedComponentHeader = pTable.getTableHeader().getDefaultRenderer().getTableCellRendererComponent(pTable, pValue, pIsSelected, pHasFocus, pRow, pColumn);
if (pColumn == 4 && pValue instanceof Double){
DecimalFormat df = new DecimalFormat("$###,##0.00");
Double d = (Double) pValue;
String s = df.format(d);
renderedComponent = mWrappedRenderer.getTableCellRendererComponent(pTable, s, pIsSelected, pHasFocus, pRow, pColumn);
}
// Set the alignment
Integer alignment = mSpecialColumnAlignmentMap.get(pColumn);
Integer width = mSpecialColumnWidthMap.get(pColumn);
if (alignment != null) {
((JLabel) renderedComponent).setHorizontalAlignment(alignment);
((JLabel) renderedComponentHeader).setHorizontalAlignment(alignment);
} else {
((JLabel) renderedComponent).setHorizontalAlignment(mDefaultAlignment);
((JLabel) renderedComponentHeader).setHorizontalAlignment(mDefaultAlignment);
}
if (width != null){
pTable.getColumnModel().getColumn(pColumn).setPreferredWidth(width);
pTable.getColumnModel().getColumn(pColumn).setMaxWidth(width);
}
return renderedComponent;
}
如您所见,我已经有了一个自定义的tablecellrenderer。我使用DecimalFormat来格式化我想要的价格。
As you can see, I already had a custom tablecellrenderer. I used the DecimalFormat to format the price as I want it.
希望这有助于其他人将来。
Hope this helps someone else out in the future.
推荐答案
HFOE是对的。但是,对于Java新手来说,这可能很棘手。请原谅我使用匿名内部类。请参阅以下示例以获取一些提示...
HFOE is right. However, this may be tricky for a Java newbie. Pardon me for using anonymous inner classes. See the following example to get some hints...
package test;
import java.awt.Component;
import java.util.ArrayList;
import java.util.List;
import javax.swing.JFrame;
import javax.swing.JScrollPane;
import javax.swing.JTable;
import javax.swing.table.AbstractTableModel;
import javax.swing.table.DefaultTableCellRenderer;
public class TableTest {
public static void main(String[] args) {
TableTest tt = new TableTest();
tt.start();
}
private void start() {
JTable t = new JTable(new AbstractTableModel() {
private static final long serialVersionUID = 1L;
private List<Double> values = new ArrayList<Double>();
{
values.add(Double.valueOf(179.70d));
values.add(Double.valueOf(299.40d));
values.add(Double.valueOf(478.80d));
values.add(Double.valueOf(89.85d));
}
@Override
public String getColumnName(int column) {
return "Double";
}
@Override
public Class<?> getColumnClass(int column) {
return Double.class;
}
@Override
public int getRowCount() {
return values.size();
}
@Override
public int getColumnCount() {
return 1;
}
@Override
public Object getValueAt(int rowIndex, int columnIndex) {
return values.get(rowIndex);
}
});
t.setDefaultRenderer(Double.class, new DefaultTableCellRenderer() {
private static final long serialVersionUID = 1L;
@Override
public Component getTableCellRendererComponent(JTable table,
Object value, boolean isSelected, boolean hasFocus, int row,
int column) {
Double d = (Double)value;
String s = "$" + String.valueOf(d.doubleValue());
Component c = super.getTableCellRendererComponent(table, s, isSelected, hasFocus,
row, column);
return c;
}
});
t.setAutoCreateRowSorter(true);
JFrame f = new JFrame();
f.setSize(320, 200);
f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
JScrollPane sp = new JScrollPane(t);
f.getContentPane().add(sp);
f.setVisible(true);
}
}
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