Compared to JList, JTable is obviously much more complicated. JTabel also inherits the consistent design style of Java, separating the data model from the drawing of the table. There are default styles and many interfaces are also provided. This not only makes Java's table design ideas clear, but also almost all personalized needs can be met.
The disadvantage is that there are too many methods encapsulated in the Java library. In order to make it as easy to understand as possible, the method names and constant names are very long, which makes the Java code look very verbose and not beautiful. But this can be solved with the code hint function in a powerful IDE.
1. Create JTabel according to the construction method; you can pass the content of the table (two-digit array), and the header (one-dimensional array)
below is the list of recruiting volunteers of our school, the name is silly.
class JTabelFrame extends JFrame
{
private String[] libVol= {
"姓名","学号","联系方式","志愿楼层","时间段"};
private Object[][] text= {
//名字纯属瞎掰
{
"楚寒冰", "07190221" ,"18602511184", "二东,二西，七西，七东" ,"周六1,周六3,周日1,周三3"},
{
"云天明", "12180243","18602511185","二东，二西，七东，七西","周二3，周四3，周日3"},
{
"陈欣"," 05181343"," 18602511211"," 五东、五西、四东、四西、三东、三西 ","周一1、周二3、周四3"},
{
"郑语嫣"," 25190133"," 18602511228"," 二东，二西，七东，七西"," 周二2、周五2"}
{
"何碧","010223","18952249826","二东，七西"，"周二3，周六2"}
};
public JTabelFrame(String title)
{
super(title);
setDefaultCloseOperation(EXIT_ON_CLOSE);
//应用JTable的构造方法JTabel(Object[][],Object[]);
*
JTable table=new JTable(text,libVol);
//设置列排列器，点击列头可对列排序
tabel.setAutoCreateRowSorter(true);
JPanel panel=new JPanel();
panel.add(new JScrollPane(table));
add(panel,BorderLayout.CENTER);
pack();
}
}
2. Customized data model, cell renderer
Like JList, Java supports custom cell renderer and data model. In the data model, you can rewrite whether the cell is editable, such as
public boolean isCellEditable(int r,int c)
{
return c==0||c==1||c==2||c==3;
}
The cell renderer and the JList process are completed. After the getTableCellRendererComponent method is implemented, the Component object is returned, and the cell is drawn with the paintComponent method. The commonly used string measurement technique is used here to put the string in the appropriate position.
In addition, the cell editor can also be used. Perform deeper operations on cells, such as adding combo boxes, events, etc. This is more complicated. You can refer to the API documentation and "Java Core Technology".
Give an example:
package JTable;
import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.Component;
import java.awt.EventQueue;
import java.awt.Font;
import java.awt.FontMetrics;
import java.awt.Graphics;
import java.sql.Date;
import javax.swing.AbstractCellEditor;
import javax.swing.DefaultCellEditor;
import javax.swing.ImageIcon;
import javax.swing.JComboBox;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.JScrollPane;
import javax.swing.JTable;
import javax.swing.UIManager;
import javax.swing.table.AbstractTableModel;
import javax.swing.table.DefaultTableCellRenderer;
import javax.swing.table.DefaultTableModel;
import javax.swing.table.TableCellRenderer;
import javax.swing.table.TableModel;
public class IdolTabel {
public static void main(String[] args)
{
EventQueue.invokeLater(()->{
IdolTableFrame frame=new IdolTableFrame("idol");
frame.setVisible(true);
});
}
}
class IdolTableFrame extends JFrame
{
private static final int DEFDAULT_WIDTH=700;
private static final int DEFDAULT_HEIGHT=500;
private JTable table;
public IdolTableFrame(String title)
{
super(title);
setSize(DEFDAULT_WIDTH, DEFDAULT_HEIGHT);
TableModel model=new IdolModel();
//添加数据模型
table=new JTable(model);
//设置默认排序器，点击表头可排序
table.setAutoCreateRowSorter(true);
table.setRowHeight(240);
table.setRowSelectionAllowed(false);
//添加单元格渲染器，对String类单元格渲染
table.setDefaultRenderer(String.class, new MyRenderer());
//对图片框单独设置
JComboBox<Integer> comb=new JComboBox<>();
for(int i=1;i<=40;i++)
comb.addItem(i);
table.getColumnModel().getColumn(2).setCellEditor(new DefaultCellEditor(comb));
table.getColumnModel().getColumn(4).setMinWidth(150);
table.getColumnModel().getColumn(4).setMinWidth(200);
add(new JScrollPane(table),BorderLayout.CENTER);
}
}
class MyRenderer extends JPanel implements TableCellRenderer
{
private static Color background;
private static String text;
private Font font=new Font(Font.SANS_SERIF,Font.PLAIN,17);
@Override
public Component getTableCellRendererComponent(JTable table, Object value, boolean isSelected, boolean hasFocus,
int row, int column) {
this.text=(String) value;
background=isSelected?new Color(64, 0, 64):column%2==1?new Color(255, 255, 225):Color.WHITE;
if(hasFocus)
{
setBorder(UIManager.getBorder("Table.focusCellHighlightBorder"));
}else setBorder(null);
return this;
}
public void paintComponent(Graphics g)
{
g.setColor(background);
g.fillRect(0, 0, getWidth(), getHeight());
g.setColor(new Color(165, 107, 77));
g.drawRect(0, 0, getWidth(), getHeight());
FontMetrics fm=g.getFontMetrics(font);
g.setColor(Color.BLACK);
g.drawString(text, (getWidth()-fm.stringWidth(text))/2, (getHeight()-fm.getHeight())/2);
}
}
class IdolModel extends AbstractTableModel
{
private String[] colnumNames= {
"姓名","国籍","年龄","出生日期","照片"};
private Object[][] cells= {
{
"白石麻衣","日本","22","1998.8.10",new ImageIcon(getClass().getResource("bsmy.jpg"))},
{
"Emma Watson","英国","30","1990.4.15",new ImageIcon(getClass().getResource("emma.jfif"))},
{
"文彩元","韩国","33","1986.11.13",new ImageIcon(getClass().getResource("wcy.jfif"))}
};
@Override
public int getRowCount() {
return cells.length;
}
@Override
public int getColumnCount() {
return cells[0].length;
}
public String getColumnName(int c)
{
return colnumNames[c];
}
@Override
public Object getValueAt(int rowIndex, int columnIndex) {
return cells[rowIndex][columnIndex];
}
public Class<?> getColumnClass(int c)
{
return cells[0][c].getClass();
}
public boolean isCellEditable(int r,int c)
{
return c==0||c==1||c==2||c==3;
}
}
The pictures are as follows:
Java's Swing components are very powerful, and the design is not complicated. To complete the customization, you only need to implement the corresponding interface.