validate a table's cell using editors

前端 未结 3 1279
太阳男子
太阳男子 2020-12-06 03:44

I have a Password field editor for my JTable. I want to display an error message if the text length is less than 8 bit when the user clicks to edit another field. I have tri

相关标签:
3条回答
  • 2020-12-06 04:01

    As I understand the question, it's about validating the input in the editor (the model protecting itself against invalid values is another story, IMO) and notifying the user about his/her error when s/he tries to commit the input.

    A simple means of doing so is using an InputVerifier:

    • implement the validation rule in its verify method
    • implement the notification in its shouldYieldFocus
    • subclass DefaultCellEditor and override its stopCellEditing to call shouldYieldFocus and return its result (aka: refuse to commit the edit)

    Some code snippet:

    final InputVerifier iv = new InputVerifier() {
    
        @Override
        public boolean verify(JComponent input) {
            JTextField field = (JTextField) input;
            return field.getText().length() > 8;
        }
    
        @Override
        public boolean shouldYieldFocus(JComponent input) {
            boolean valid = verify(input);
            if (!valid) {
                JOptionPane.showMessageDialog(null, "invalid");
            }
            return valid;
        }
    
    };
    DefaultCellEditor editor = new DefaultCellEditor(new JTextField()) {
        {
            getComponent().setInputVerifier(iv);
        }
    
        @Override
        public boolean stopCellEditing() {
            if (!iv.shouldYieldFocus(getComponent())) return false;
            return super.stopCellEditing();
        }
    
        @Override
        public JTextField getComponent() {
            return (JTextField) super.getComponent();
        }
    
    };
    
    JTable table = new JTable(10, 2);
    table.setDefaultEditor(Object.class, editor);
    
    0 讨论(0)
  • 2020-12-06 04:09

    Override stopCellEditing() and implement the condition inside it.

     class PasswordEditor extends DefaultCellEditor 
    {
    
        TextBox m_passWord = new TextBox(); 
        public PasswordEditor() {
            super(new TextBox());
        }
    
                @Override
        public boolean stopCellEditing()
        {
            if(getCellEditorValue().toString().length() < 8)
            {
                JOptionPane.showMessageDialog(UsmUserView.this.m_Parent, "Password Must Be 8 Bytes Long !! Please Check");
                return false;
            }
            fireEditingStopped();
            return true;
        }
    
        @Override
        public Object getCellEditorValue() {
    
            return this.m_passWord.getText();
        }
    
        @Override
        public Component getTableCellEditorComponent(JTable table,
                Object value, boolean isSelected, int row, int column) {
    
            Object fieldValue = value;
            if(null == fieldValue)
                fieldValue = Constants.EMPTY_STRING;
    
            this.m_passWord.setEditable(true);
            this.m_passWord.setText(fieldValue.toString());
            return this.m_passWord;
        }
    
    
    }
    
    0 讨论(0)
  • 2020-12-06 04:12

    Override the stopCellEditing() and u can try the below code to get the focus for the error cell.

    class PasswordEditor extends DefaultCellEditor 
    {
    
        private TextBox m_passWord = new TextBox(); 
        public PasswordEditor() {
            super(new TextBox());
        }
    
                @Override
        public boolean stopCellEditing()
        {
            if(getCellEditorValue().toString().length() < 8)
            {
                // Text box will get the focus and will shown in Red line as border for that cell.
                TextBox aTextBox = (TextBox)getComponent();
                aTextBox.setBorder(new LineBorder(Color.red));
                aTextBox.selectAll();
                aTextBox.requestFocusInWindow();
                JOptionPane.showMessageDialog(UsmUserView.this.m_Parent, "Password Must Be 8 Bytes Long !! Please Check");
                return false;
            }
            return super.stopCellEditing();
        }
    
        @Override
        public Object getCellEditorValue() {
    
            return this.m_passWord.getText();
        }
    
        @Override
        public Component getTableCellEditorComponent(JTable table,
                Object value, boolean isSelected, int row, int column) {
    
            Object fieldValue = value;
            if(null == fieldValue)
                fieldValue = Constants.EMPTY_STRING;
    
            this.m_passWord.setEditable(true);
            this.m_passWord.setText(fieldValue.toString());
            return this.m_passWord;
        }
    
    
    }
    
    0 讨论(0)
提交回复
热议问题