Swing Hacks

120

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Chapter 3, Tables and Trees

#23 Let Your JTables Do the Sorting

HACK

When run, the table will be sorted by column 0, which contains Strings, as

seen in Figure 3-5.

If you click the Sort 2 button (yes, the numbering is human-readable, and

thus it’s one greater than actual column indices), the table will immediately

sort by the

Integers in the middle column, as seen in Figure 3-6.

The color column is next. Click Sort 3 to see the table sort by the colors, as

seen in Figure 3-7.

Component returnMe =

super.getTableCellRendererComponent (table, value,

isSelected,

hasFocus, row, col);

if (value instanceof Color) {

Color color = (Color) value;

returnMe.setBackground (color);

if (returnMe instanceof JLabel) {

JLabel jl = (JLabel) returnMe;

jl.setOpaque(true);

jl.setText ("");

}

}

return returnMe;

}

}

Figure 3-5. JTable sorted automatically by its first column

Example 3-11. The Comparator and TableCellRenderer handle color values in sorting a

table test (continued)

Let Your JTables Do the Sorting #23

Chapter 3, Tables and Trees

|

121

HACK

Finally, add in another row with the “More data” button. Because its color

is solid red (maximum brightness), it will appear last when sorting by color.

This is seen in Figure 3-8.

Figure 3-6. Sorting JTable by its second column

Figure 3-7. Sorting JTable by its third column ...