Focus问题请教

Question

在一个JTextField里面，我写了事件，如果里面输入的Value不符合条件，则光标一直在这个JTextField里面，
不能移动到别的JTextField里面，如何让焦点一直在JtextField？谢谢！

Answer 1

requestFocus()应该是有用的 J2SE里
import java.awt.FlowLayout;
import javax.swing.JFrame;
import javax.swing.JTextField;public class Test { public static void main(String args[]) {
JFrame jf = new JFrame();
JTextField jtf1 = new JTextField();
JTextField jtf2 = new JTextField();
jtf1.setColumns(10);
jtf2.setColumns(10);
jf.add(jtf1);
jf.add(jtf2);
jf.setLayout(new FlowLayout());
jf.setSize(400, 150);
jf.setVisible(true);
jf.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
while (true) {
jtf1.requestFocus();
}
}}

Answer 2

参照以下代码写：
JTextField tf_panme=new JTextField();
tf_pname.setInputVerifier(new InputVerifier() { @Override
public boolean verify(JComponent input) {
try {
JTextField tf = (JTextField) input;
if (tf.getText().equalsIgnoreCase("")) {
setStatus("姓名不能为空!");
return false;
}
} catch (NumberFormatException e) {
setStatus("格式不正确,应为整数!");
return false;
}
return true;
}
});

Answer 3

不好意思，我的是一个JTable,Jtable里面用JTextField,
按照上面各位的方法还是不行，是不是需要验证Jtable一个单元格
里面的的值，如果不符合，就不让光标移出这格单元格？
private JTextField editor;
private TableColumn tc;主要代码：        model = new DefaultTableModel(data, Header) {
                    public boolean isCellEditable(int rowindex, 
                                                  int columnindex) {
                        String strtmp = (String)table.getValueAt(rowindex,1);
                        int row = rowindex;
                        if (strtmp.equals("C")){
                            if ((rowindex==row)&&(columnindex>2)){
                                return false;
                            }
                        }
                        return true;
                    }
                };
        //JTable table = new JTable(model);
        table = new JTable(model);
        JScrollPane jsp = new JScrollPane(table);        colmodel = table.getColumnModel();
        //=========Set the table Cell Width ================
        colmodel.getColumn(0).setPreferredWidth(100);
        colmodel.getColumn(1).setPreferredWidth(10);
        colmodel.getColumn(2).setPreferredWidth(100);
        colmodel.getColumn(3).setPreferredWidth(100);
        //=========set the Cell for Textfield ================
        for (int index = 2; index < 6; index++) {
            tc = colmodel.getColumn(index);
            editor = new JTextField();
            MyCellEditor celleditor = new MyCellEditor(editor);
            celleditor.setClickCountToStart(0);
            tc.setCellEditor(celleditor);
        }
//======这一部分生成JTextField的约束
    class MyCellEditor extends DefaultCellEditor {
        public MyCellEditor(JTextField textField) {
            super(textField);
            // TODO Auto-generated constructor stub 
        }        public boolean stopCellEditing() {
            //return true;
            int row = table.getSelectedRow();
            int col = table.getSelectedColumn();
            if ((row==0)&&(col==2)){
              String value = (String)this.getCellEditorValue();
                   editor.setInputVerifier(new InputVerifier() {
                            //@Override 
                            public boolean verify(JComponent input) {
                                try {
                                    JTextField tf = (JTextField)input;
                                    if (tf.getText().equalsIgnoreCase("")) {
                                        //setStatus("wqeq");
                                         JOptionPane.showMessageDialog(null,"Error Format.");
                                        return false;
                                    }
                                } catch (NumberFormatException e) {
                                    //setStatus("qweq!");
                                     JOptionPane.showMessageDialog(null,"Error Format.");
                                    return false;
                                }
                                return true;
                            }
                        });
              JOptionPane.showMessageDialog(null,"Error Format.");
            }
            return super.stopCellEditing();
        }
    }还是不行，大家帮忙呀

Answer 4

[code]
textField.setInputVerifier(new InputVerifier(){
    public boolean verify(JComponent component){
         JTextField field=(JTextField)component;
         return isValid(field.getText());
    }
});
[/code]试试这样，isValid是你的判断输入合法性的函数

Answer 5

靠，怎么代码没发上。textField.setInputVerifier(new InputVerifier(){
    public boolean verify(JComponent component){
         JTextField field=(JTextField)component;
         return isValid(field.getText());
    }
});
试试这样，isValid是你的判断输入合法性的函数