關於簡單計算器中的佈局

Question

嗨，我想嘗試使用編碼大小，佈局等自己製作一個計算器（試圖不使用NetBeans，它不是一個家庭作業）。但我面臨着一個關於空白空間的問題。我有一個TextArea和按鈕，但正如你可以看到下面我不能處理這個空間問題。這裏是我的代碼，

import java.awt.BorderLayout; 
import java.awt.Color; 
import java.awt.FlowLayout; 
import java.awt.GridLayout; 

import javax.swing.JButton; 
import javax.swing.JFrame; 
import javax.swing.JPanel; 
import javax.swing.JSeparator; 
import javax.swing.JTextArea; 

public class calculator extends JFrame { 

    public calculator(){ 

     initComponents(); 

    } 

    private void initComponents(){ 

     JPanel panelScreen = new JPanel(new GridLayout(0,1)); 

     JTextArea screen = new JTextArea(); 
     panelScreen.add(screen); 

     JFrame frame = new JFrame("CALCULATOR"); 
     frame.setDefaultCloseOperation(EXIT_ON_CLOSE); 

     JPanel panelButtons = new JPanel(new GridLayout(3,3)); 

     JButton oneButton = new JButton("1"); 
     panelButtons.add(oneButton); 

     JButton twoButton = new JButton("2"); 
     panelButtons.add(twoButton); 

     JButton threeButton = new JButton("3"); 
     panelButtons.add(threeButton); 

     JButton fourButton = new JButton("4"); 
     panelButtons.add(fourButton); 

     JButton fiveButton = new JButton("5"); 
     panelButtons.add(fiveButton); 

     JButton sixButton = new JButton("6"); 
     panelButtons.add(sixButton); 

     JButton sevenButton = new JButton("7"); 
     panelButtons.add(sevenButton); 

     JButton eightButton = new JButton("8"); 
     panelButtons.add(eightButton); 

     JButton nineButton = new JButton("9"); 
     panelButtons.add(nineButton); 

     frame.getContentPane().add(panelScreen, BorderLayout.NORTH); 
     //frame.getContentPane().add(new JSeparator(), BorderLayout.CENTER); 
     frame.getContentPane().add(panelButtons, BorderLayout.SOUTH); 
     frame.setBounds(50, 50, 500, 500); 
     frame.setResizable(false); 
     //frame.pack(); 
     frame.setVisible(true); 


    } 


    public static void main(String[] args) { 

     new calculator(); 

    } 

} 

和這個程序的圖片;

我很感激，如果你能幫助我。反正感謝:)

Answer 1

import java.awt.*; 

import javax.swing.*; 
import javax.swing.border.EmptyBorder; 

// no need to extend frame! 
//public class Calculator extends JFrame { 
public class Calculator { 

    public Calculator(){  
     initComponents();  
    } 

    private void initComponents(){ 
     // I find it easier to create a panel and SET it as the content pane 
     JPanel gui = new JPanel(new BorderLayout(5,5)); 
     // add some padding to the main GUI 
     gui.setBorder(new EmptyBorder(4,4,4,4)); 

     // not needed if only a single compoinent is to be added! 
     //JPanel panelScreen = new JPanel(new GridLayout(0,1)); 

     // add some constraints to make the output field bigger. 
     // if it is intended to be single line, a JTextField should be used. 
     JTextArea screen = new JTextArea(2,25); 
     gui.add(screen, BorderLayout.NORTH); 
     //panelScreen.add(screen); 

     JFrame frame = new JFrame("CALCULATOR"); 
     frame.setContentPane(gui); 

     frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); 

     // add padding around the buttons 
     JPanel panelButtons = new JPanel(new GridLayout(3,3,4,4)); 

     JButton oneButton = new JButton("1"); 
     panelButtons.add(oneButton); 

     JButton twoButton = new JButton("2"); 
     panelButtons.add(twoButton); 

     JButton threeButton = new JButton("3"); 
     panelButtons.add(threeButton); 

     JButton fourButton = new JButton("4"); 
     panelButtons.add(fourButton); 

     JButton fiveButton = new JButton("5"); 
     panelButtons.add(fiveButton); 

     JButton sixButton = new JButton("6"); 
     panelButtons.add(sixButton); 

     JButton sevenButton = new JButton("7"); 
     panelButtons.add(sevenButton); 

     JButton eightButton = new JButton("8"); 
     panelButtons.add(eightButton); 

     JButton nineButton = new JButton("9"); 
     panelButtons.add(nineButton); 

     //frame.getContentPane().add(new JSeparator(), BorderLayout.CENTER); 

     // Add the buttons to the CENTER and they will 
     // fill whatever space they are provided. 
     gui.add(panelButtons, BorderLayout.CENTER); 
     //frame.setBounds(50, 50, 500, 500); 
     //frame.setResizable(false); 
     frame.pack(); 
     frame.setVisible(true); 
    }  

    public static void main(String[] args) {  
     java.awt.EventQueue.invokeLater(new Runnable() { 

     @Override 
     public void run() { 
      new Calculator(); 
     } 
     });  
    }  
} 

Answer 2

幾點建議：

1. 不要設置Jframe的大小，而事實上沒有設置任何尺寸。
2. 給所有組件調用包以設置自己的尺寸。
3. 如果您希望更大的按鈕，請考慮更改其字體的大小。

例如，

import java.awt.BorderLayout; 
import java.awt.Font; 
import java.awt.GridLayout; 

import javax.swing.*; 

public class Calc2 { 
    public static final String[][] BUTTON_TEXTS = { 
     {"7", "8", "9", "+"}, 
     {"4", "5", "6", "-"}, 
     {"1", "2", "3", "*"}, 
     {"0", ".", "/", "="} 
    }; 
    public static final Font BTN_FONT = new Font(Font.SANS_SERIF, Font.BOLD, 24); 

    private static void createAndShowGui() { 
     JTextField field = new JTextField(10); 
     field.setFont(BTN_FONT.deriveFont(Font.PLAIN)); 
     JPanel btnPanel = new JPanel(new GridLayout(BUTTON_TEXTS.length, 
      BUTTON_TEXTS[0].length)); 

     for (int i = 0; i < BUTTON_TEXTS.length; i++) { 
     for (int j = 0; j < BUTTON_TEXTS[i].length; j++) { 
      JButton btn = new JButton(BUTTON_TEXTS[i][j]); 
      btn.setFont(BTN_FONT); 
      btnPanel.add(btn); 
     } 
     } 

     JPanel mainPanel = new JPanel(new BorderLayout()); 
     mainPanel.add(field, BorderLayout.PAGE_START); 
     mainPanel.add(btnPanel, BorderLayout.CENTER); 


     JFrame frame = new JFrame("Calc2"); 
     frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); 
     frame.getContentPane().add(mainPanel); 
     frame.pack(); 
     frame.setLocationRelativeTo(null); 
     frame.setVisible(true); 
    } 

    public static void main(String[] args) { 
     SwingUtilities.invokeLater(new Runnable() { 
     public void run() { 
      createAndShowGui(); 
     } 
     }); 
    } 
} 

Answer 3

1. 讀Laying Out Components Within a Container
2. 實施適當的佈局（S）

編輯 -

快速解決方案 - 用BoxLayout替換JFrame佈局管理器。 setLayout(new BoxLayout(this, BoxLayout.PAGE_AXIS))）。

Answer 4

快速和髒溶液：

取消註釋的setBounds（）並將其更改爲frame.setBounds（50,50，150，125）;然而，這並不是理想的解決方案。

我會重新設計我使用我的佈局面板的方式，使其更靈活，使用不同的頂層佈局。當前的BorderLayout（默認值）不適合此類設計。

Answer 5

您可能會喜歡研究這個遵循@HFOE和@mre建議的example。請注意，「大小」在代碼中無處顯示。