public void intiInterface()
        {
            try
            {
                // ͱ
                JButton expressionBtn;
                expressionBtn = new JButton("Send Expression", new ImageIcon(URLDecoder.decode(this.getClass().getResource("/").toString() + "/imgs/zk.gif", "utf-8")));
                
                // font size
                JLabel fontSizeLab = new JLabel("    Size: ");
                JComboBox<String> fontSizeCombbox = new JComboBox<>();
                fontSizeCombbox.addItem("10");
                fontSizeCombbox.addItem("12");
                fontSizeCombbox.addItem("14");
                fontSizeCombbox.addItem("16");
                fontSizeCombbox.addItem("18");
                fontSizeCombbox.addItem("22");
                fontSizeCombbox.setSelectedItem("12"); // ĬϴСΪ 12
                
                // font style
                JButton fontBoldBtn = new JButton("Bold");
                JButton fontItalicBtn = new JButton("Italic");
                
                // save records
                JButton saveRecordsBtn = new JButton("Save Records");
                
                // layout
                this.setLayout(new FlowLayout(LEADING, 10, 5));
                
                this.add(fontSizeLab);
                this.add(fontSizeCombbox);
                this.add(fontBoldBtn);
                this.add(fontItalicBtn);
                this.add(expressionBtn);
                this.add(saveRecordsBtn);
                
                // Ӽ
                fontBoldBtn.addActionListener(this);
                fontItalicBtn.addActionListener(this);
                saveRecordsBtn.addActionListener(this);
                expressionBtn.addActionListener(this);
                fontSizeCombbox.addItemListener(this);
                fontBoldBtn.setActionCommand("SetFontBlod");
                fontItalicBtn.setActionCommand("SetFontItalic");
                expressionBtn.setActionCommand("SendExpression");
                saveRecordsBtn.setActionCommand("SaveRecords");
                
                // òɸ
                this.setFloatable(false);
                
            } catch(UnsupportedEncodingException e)
            {
                e.printStackTrace();
            }
        }