JFrameにキーリスナーを追加するには？

Question

私は自分のキーでロケットアニメーションをコントロールしようとしていますが、KeyListenerメソッドを使用しようとしましたが、私のプログラムはキープレスに反応しません。私はJFrameにキーリストを追加しようとしましたが、JFrameは別の静的メソッドなので、呼び出さない。あなたがそれを実行する場合は、イメージを持っていませんが、実行する場合は四角形で置き換えてください。私の間違いを教えてください。前もって感謝します。ここで

は私のコードです：

import java.awt.*; 
import hsa.Console; 
import javax.imageio.*; 
import java.io.*; 

import java.awt.Graphics; 
import java.awt.Color; 

import java.awt.event.ActionEvent; 
import java.awt.event.ActionListener; 
import java.awt.event.KeyListener; 
import java.awt.event.KeyEvent; 

import javax.swing.*; 
import javax.swing.JPanel; 
import javax.swing.JFrame; 
import javax.swing.Timer; 

import java.util.Arrays; 

public class MA_RocketLauncher extends JPanel implements ActionListener, KeyListener 
{ 

    static Console c; 

    //***********************************Main Program********************************* 

    public static void main (String[] args) 
    { 

     c = new Console (27, 85); 

     MainProgram(); 

    } 

    //********************************JFrame****************************************** 

    public static void JFrame() 
    { 

     JFrame jf = new JFrame(); 

     MA_RocketLauncher r = new MA_RocketLauncher(); 

     jf.setSize(692, 542); 
     jf.setTitle("Rocket Launcher"); 
     jf.setVisible(true); 
     jf.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); 
     jf.setResizable(false); 
     jf.add(r); 

    } 

    //********************************All Methods************************************* 

    public static void MainProgram() 
    { 

     //IntroMessage(); 
     //Password(); 

     JFrame(); 

    } 

    //***********************************Timer**************************************** 

    Timer t = new Timer(12, this); 

    int y = 240, velY = 0, y2 = 300, velY2 = 0, x = 20, velX = 0, x2 = -5, velX2 = 0, y3 = -5, velY3 = 0, 
     y4 = -5, velY4 = 0; 

    //*********************************Rocket***************************************** 

    public void paintComponent (Graphics c) 
    { 

     super.paintComponent (c); 

     Color darkGrey = new Color (32, 32, 32); 

     c.setColor (darkGrey); 
     c.fillRect (0, 0, 700, 550); 

     c.setColor (Color.black); 
     c.drawRect (18, 0, 639, 379); 

     Image picture3 = loadImage ("Canada.png"); 
     c.drawImage (picture3, 19, 1, null); 

     Font f2 = new Font ("Monaco", Font.BOLD, 20); 

     c.setColor (Color.white); 
     c.setFont (f2); 

     c.drawString ("LIVE VIEW", 550, 25); 

     Font f = new Font ("Courier New", Font.BOLD, 30); 

     c.setColor (Color.red); 
     c.setFont (f); 

     c.drawString ("Status: ", 30, 420); 

     c.setColor (Color.green); 

     c.drawString ("  Launching!", 30, 420); 

     Font f3 = new Font ("Courier New", Font.BOLD, 25); 

     c.setFont (f3); 

     c.drawString ("Clearance Level 1 Achieved", 30, 460); 
     c.drawString ("ETA: 30 seconds", 30, 500); 

     Image picture2 = loadImage ("circle_flag_us_america_united_states-512.png"); 
     c.drawImage (picture2, 627, 475, null); 

     Font f1 = new Font ("Courier New", Font.BOLD, 12); 

     c.setColor (Color.green); 
     c.setFont (f1); 

     c.drawString ("Property of the United States government", 340, 490); 
     c.drawString ("Confidential Information", 450, 505); 

     Image picture4 = loadImage ("RocketUp.png"); 

     c.drawImage (picture4, 100, y, null); 
     c.drawImage (picture4, 500, y, null); 

     t.start(); 

     addKeyListener(this); 

     setFocusable(true); 

     setFocusTraversalKeysEnabled(false); 

     if (y < -130) 
     { 

      c.setColor (darkGrey); 
      c.fillRect (0, 0, 700, 550); 

      c.setColor (Color.black); 
      c.drawRect (18, 0, 639, 379); 

      Image picture5 = loadImage ("Sky.png"); 

      c.drawImage (picture5, 19, 1, null); 

      Image picture6 = loadImage ("RocketUpMedium.png"); 

      c.drawImage (picture6, 100, y2, null); 
      c.drawImage (picture6, 500, y2, null); 

      c.setColor (Color.white); 
      c.setFont (f2); 

      c.drawString ("LIVE VIEW", 550, 25); 

      c.setColor (Color.red); 
      c.setFont (f); 

      c.drawString ("Status: ", 30, 420); 

      c.setColor (Color.green); 

      c.drawString ("  Launched!", 30, 420); 

      c.setFont (f3); 

      c.drawString ("Clearance Level 2 Achieved", 30, 460); 
      c.drawString ("ETA: 20 seconds", 30, 500); 

      c.drawImage (picture2, 627, 475, null); 

      c.setColor (Color.green); 
      c.setFont (f1); 

      c.drawString ("Property of the United States government", 340, 490); 
      c.drawString ("Confidential Information", 450, 505); 

      if (y2 < -130) 
      { 

       c.setColor (darkGrey); 
       c.fillRect (0, 0, 700, 550); 

       c.setColor (Color.black); 
       c.drawRect (18, 0, 639, 379); 

       c.setFont (f2); 
       c.setColor (Color.white); 

       c.drawString ("LIVE VIEW", 550, 25); 

       c.setColor (Color.red); 
       c.setFont (f); 

       c.drawString ("Status: ", 30, 420); 

       c.setColor (Color.green); 

       c.drawString ("  En Route!", 30, 420); 

       c.setFont (f3); 

       c.drawString ("Clearance Level 3 Achieved", 30, 460); 
       c.drawString ("ETA: 10 seconds", 30, 500); 

       c.drawImage (picture2, 627, 475, null); 

       c.setColor (Color.green); 
       c.setFont (f1); 

       c.drawString ("Property of the United States government", 340, 490); 
       c.drawString ("Confidential Information", 450, 505); 

       Image picture7 = loadImage ("Space.jpg"); 

       c.drawImage (picture7, 19, 1, null); 

       c.setFont (f2); 
       c.setColor (Color.white); 

       c.drawString ("LIVE VIEW", 550, 25); 

       Image picture8 = loadImage ("Earth.png"); 

       c.drawImage (picture8, 19, 1, null); 

       Image picture9 = loadImage ("RocketRightSmall.png"); 

       c.drawImage (picture9, x, 100, null); 
       c.drawImage (picture9, x, 200, null); 

       c.setColor (darkGrey); 
       c.fillRect (658, 0, 40, 379); 

       if (x > 658) 
       { 

        c.setColor (darkGrey); 
        c.fillRect (0, 0, 700, 550); 

        c.setColor (Color.black); 
        c.drawRect (18, 0, 639, 379); 

        c.drawImage (picture7, 19, 1, null); 

        c.setFont (f2); 
        c.setColor (Color.white); 

        c.drawString ("LIVE VIEW", 550, 25); 

        c.setColor (Color.red); 
        c.setFont (f); 

        c.drawString ("Status: ", 30, 420); 

        c.setColor (Color.green); 

        c.drawString ("  Arriving!", 30, 420); 

        c.setFont (f3); 

        c.drawString ("Clearance Level 4 Achieved", 30, 460); 
        c.drawString ("ETA: 5 seconds", 30, 500); 

        c.drawImage (picture2, 627, 475, null); 

        c.setColor (Color.green); 
        c.setFont (f1); 

        c.drawString ("Property of the United States government", 340, 490); 
        c.drawString ("Confidential Information", 450, 505); 

        Image picture10 = loadImage ("Moon.png"); 

        c.drawImage (picture10, 400, 100, null); 

        c.drawImage (picture9, x2, 100, null); 
        c.drawImage (picture9, x2, 200, null); 

        c.setColor (darkGrey); 
        c.fillRect (0, 0, 19, 379); 

        if (x2 > 450) 
        { 

         c.setColor (darkGrey); 
         c.fillRect (0, 0, 700, 550); 

         c.setColor (Color.black); 
         c.drawRect (18, 0, 639, 379); 

         c.drawImage (picture7, 19, 1, null); 

         c.setFont (f2); 
         c.setColor (Color.white); 

         c.drawString ("LIVE VIEW", 550, 25); 

         Image picture11 = loadImage ("MoonBig.png"); 

         c.drawImage (picture11, 150, 250, null); 

         c.setColor (darkGrey); 
         c.fillRect (0, 380, 700, 170); 

         c.drawImage (picture2, 627, 475, null); 

         c.setColor (Color.green); 
         c.setFont (f1); 

         c.drawString ("Property of the United States government", 340, 490); 
         c.drawString ("Confidential Information", 450, 505); 

         c.setColor (Color.red); 
         c.setFont (f); 

         c.drawString ("Status: ", 30, 420); 

         c.setColor (Color.green); 

         c.drawString ("  Landing!", 30, 420); 

         c.setFont (f3); 

         c.drawString ("Clearance Level 5 Achieved", 30, 460); 
         c.drawString ("ETA: 2.5 seconds", 30, 500); 

         c.drawImage (picture6, 290, y3, null); 
         c.drawImage (picture6, 390, y3, null); 

         if (y3 > 290) 
         { 

          c.setColor (darkGrey); 
          c.fillRect (0, 0, 700, 550); 

          c.setColor (Color.black); 
          c.drawRect (18, 0, 639, 379); 

          Image picture12 = loadImage ("MoonSurface.jpg"); 
          c.drawImage (picture12, 19, 1, null); 

          c.setFont (f2); 
          c.setColor (Color.white); 

          c.drawString ("LIVE VIEW", 550, 25); 

          c.drawImage (picture2, 627, 475, null); 

          c.setColor (Color.green); 
          c.setFont (f1); 

          c.drawString ("Property of the United States government", 340, 490); 
          c.drawString ("Confidential Information", 450, 505); 

          c.setColor (Color.red); 
          c.setFont (f); 

          c.drawString ("Status: ", 30, 420); 

          c.setColor (Color.green); 

          c.drawString ("  Taxi!", 30, 420); 

          c.setFont (f3); 

          c.drawString ("Clearance Level 6 Achieved", 30, 460); 
          c.drawString ("ETA: 1 second", 30, 500); 

          c.drawImage (picture4, 100, y4, null); 
          c.drawImage (picture4, 500, y4, null); 

          if (y4 > 260) 
          { 

           c.setColor (darkGrey); 
           c.fillRect (0, 0, 700, 550); 

           c.setColor (Color.black); 
           c.drawRect (18, 0, 639, 379); 

           c.drawImage (picture12, 19, 1, null); 

           c.setFont (f2); 
           c.setColor (Color.white); 

           c.drawString ("LIVE VIEW", 550, 25); 

           c.drawImage (picture2, 627, 475, null); 

           c.setColor (Color.green); 
           c.setFont (f1); 

           c.drawString ("Property of the United States government", 340, 490); 
           c.drawString ("Confidential Information", 450, 505); 

           c.setColor (Color.red); 
           c.setFont (f); 

           c.drawString ("Status: ", 30, 420); 

           c.setColor (Color.green); 

           c.drawString ("  Landed!", 30, 420); 

           c.setFont (f3); 

           c.drawString ("Clearance Level 7 Achieved", 30, 460); 
           c.drawString ("ETA: 0 seconds", 30, 500); 

           c.drawImage (picture4, 100, 260, null); 
           c.drawImage (picture4, 500, 260, null); 

           c.setColor(Color.green); 

           Font f4 = new Font ("Monaco", Font.BOLD, 100); 
           c.setFont(f4); 

           c.drawString("SUCCESS", 90, 200); 

          } 

         } 

        } 

       } 

      } 

     } 

    } 

    //********************************Action Listener Method************************** 

    public void actionPerformed (ActionEvent e) 
    { 

     if (y < -130) 
     { 
      y2 = y2 - velY2; 

      if (y2 < -130) 
      { 
       x = x + velX; 

       if (x > 658) 
       { 

        x2 = x2 + velX2; 

        if (x2 > 450) 
        { 

         y3 = y3 + velY3; 

         if (y3 > 290) 
         { 

          y4 = y4 + velY4; 

         } 

        } 

       } 

      } 

     } 

     y = y - velY; 

     repaint(); 

    } 

    //******************************Key Listener Method******************************* 

    public void keyPressed (KeyEvent e) 
    { 

     int c = e.getKeyCode(); 

     if (c == KeyEvent.VK_LEFT) 
     { 

      velX = -1; 

      velX2 = -1; 

      velY = 0; 

      velY2 = 0; 

      velY3 = 0; 

      velY4 = 0; 

     } 

     if (c == KeyEvent.VK_UP) 
     { 

      velY = -1; 

      velY2 = -1; 

      velY3 = -1; 

      velY4 = -1; 

      velX = 0; 

      velX2 = 0; 

     } 

     if (c == KeyEvent.VK_RIGHT) 
     { 

      velX = +1; 

      velX2 = +1; 

      velY = 0; 

      velY2 = 0; 

      velY3 = 0; 

      velY4 = 0; 

     } 

     if (c == KeyEvent.VK_DOWN) 
     { 

      velY = +1; 

      velY2 = +1; 

      velY3 = +1; 

      velY4 = +1; 

      velX = 0; 

      velX2 = 0; 

     } 

    } 

    public void keyTyped(KeyEvent e){} 

    public void keyReleased(KeyEvent e){} 

    //********************************Image Loader Method***************************** 

    public static Image loadImage (String name) 
    { 

     Image img = null; 

     try 
     { 

      img = ImageIO.read (new File (name)); 

     } 

     catch (IOException e) 
     { 

     } 

     return img; 

    } 

Answer 1

paintComponent(...)だけ絵を行うために使用する必要があります。それはべきではない：

1. 、読み込んだ画像ファイルパネルの
2. セットのプロパティ：setFocusKeysEnabled setFocusable（..）、（...）
3. は、パネルにリスナーを追加します。addKeyListener（...）

上記のコードはすべて、コンストラクタで1つにする必要があります。

paintComponent()メソッドは、repaint（）が実行されるたびに呼び出され、画像の読み取りを継続したり、リスナーを追加したりしないようにします。

あなたは見るためにあまりにも多くのコードを投稿しました。問題が発生したら、問題を示す適切なSSCCEを投稿してください。

リスナーが動作しない通常の理由は、パネルにフォーカスがないためです。

一般的な解決方法は、KeyListenerではなくKey Bindingsを使用することです。詳細は、HOw to Use Key BindingsのSwingチュートリアルのセクションを参照してください。

Answer 2

私が間違っていたのは、タイマーとキーコマンドを痛みのコンポーネントの中に入れていたので、私がしなければならなかったのはパブリッククラスを作成してそこにコマンドを置くことでした。私はまた、メインプログラムから画像をロードし、上記の回答の状態と同じように、塗料コンポーネントにそれらを呼び出しました。

これは私の作業コードの一部です： `だから私は間違って何をやっていた痛みcomponent`内タイマーやキーコマンドを入れていた

import java.awt.*; 
    import hsa.Console; 
    import javax.imageio.*; 
    import java.io.*; 

    import java.awt.Graphics; 
    import java.awt.Color; 

    import java.awt.event.ActionEvent; 
    import java.awt.event.ActionListener; 
    import java.awt.event.KeyListener; 
    import java.awt.event.KeyEvent; 

    import javax.swing.*; 
    import javax.swing.JPanel; 
    import javax.swing.JFrame; 
    import javax.swing.Timer; 

    import java.util.Arrays; 

    public class MA_RocketLauncher extends JPanel implements ActionListener, KeyListener 
    { 

     static Console c; 

     //***********************************Main Program********************************* 

     public static void main (String[] args) 
     { 

      c = new Console (27, 85); 

      MainProgram(); 

     } 

     //********************************JFrame****************************************** 

     public static void JFrame() 
     { 

      JFrame jf = new JFrame(); 

      MA_RocketLauncher r = new MA_RocketLauncher(); 

      jf.setSize(692, 542); 
      jf.setTitle("Rocket Launcher"); 
      jf.setVisible(true); 
      jf.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); 
      jf.setResizable(false); 
      jf.add(r); 

     } 

     //********************************All Methods************************************* 

     public static void MainProgram() 
     { 

      //IntroMessage(); 
      //Password(); 

      JFrame(); 

     } 

     //***********************************Timer**************************************** 

     Timer t = new Timer(10, this); 

     int y = 240, velY = 0, y2 = 300, velY2 = 0, x = 20, velX = 0, x2 = -5, velX2 = 0, y3 = -5, velY3 = 0, 
      y4 = -5, velY4 = 0; 

     public MA_RocketLauncher() 
     { 

      t.start(); 

      addKeyListener(this); 

      setFocusable(true); 

      setFocusTraversalKeysEnabled(false); 

     } 

     //**********************************Images**************************************** 

     Image picture2 = loadImage ("circle_flag_us_america_united_states-512.png"); 

     Image picture3 = loadImage ("Canada.png"); 

     Image picture4 = loadImage ("RocketUp.png"); 

     Image picture5 = loadImage ("Sky.png"); 

     Image picture6 = loadImage ("RocketUpMedium.png"); 

     Image picture7 = loadImage ("Space.jpg"); 

     Image picture8 = loadImage ("Earth.png"); 

     Image picture9 = loadImage ("RocketRightSmall.png"); 

     Image picture10 = loadImage ("Moon.png"); 

     Image picture11 = loadImage ("MoonBig.png"); 

     Image picture12 = loadImage ("MoonSurface.jpg"); 

     //*********************************Rocket***************************************** 

     public void paintComponent (Graphics c) 
     { 

      super.paintComponent (c); 

      //Graphics 

     } 

     //********************************Action Listener Method************************** 

     public void actionPerformed (ActionEvent e) 
     { 

      if (y < -130) 
      { 
       y2 = y2 - velY2; 

       if (y2 < -130) 
       { 
        x = x + velX; 

        if (x > 658) 
        { 

         x2 = x2 + velX2; 

         if (x2 > 450) 
         { 

          y3 = y3 + velY3; 

          if (y3 > 290) 
          { 

           y4 = y4 + velY4; 

          } 

         } 

        } 

       } 

      } 

      y = y - velY; 

      repaint(); 

     } 

     //******************************Key Listener Method******************************* 

     public void keyPressed (KeyEvent e) 
     { 

      int c = e.getKeyCode(); 

      if (c == KeyEvent.VK_LEFT) 
      { 

       velX = -1; 

       velX2 = -1; 

      } 

      if (c == KeyEvent.VK_UP) 
      { 

       if (y < -130) 
       { 

        y = -1000; 

       } 

       else 
       { 

        velY = 1; 

       } 

       if (y2 < -130) 
       { 

        y2 = -1000; 

       } 

       else 
       { 

        velY2 = 1; 

       } 

       velY3 = -1; 

       velY4 = -1; 

      } 

      if (c == KeyEvent.VK_RIGHT) 
      { 

       velX = +1; 

       velX2 = +1; 

      } 

      if (c == KeyEvent.VK_DOWN) 
      { 

       velY = -1; 

       velY2 = -1; 

       velY3 = +1; 

       velY4 = +1; 

      } 

     } 

     public void keyTyped(KeyEvent e){} 

     //*****************************Key Released Method******************************** 

     public void keyReleased(KeyEvent e) 
     { 

      velX = 0; 

      velX2 = 0; 

      velY = 0; 

      velY2 = 0; 

      velY3 = 0; 

      velY4 = 0; 

     } 
}