跳精靈

Question

我只想使用android（沒有游戲引擎）來制作一個sprite \\ bitmap。 我無法僅使用畫布和視圖來找到有關如何在android中執行此操作的教程，但確實找到了xna的教程（ http://www.xnadevelopment.com/tutorials/thewizardjumping/thewizardjumping.shtml ），並且我試圖用android提供的工具重新創建它。 我能夠使用教程代碼使角色左右移動，但是使它跳轉只是不起作用。

這是我的精靈課程：

package com.example.spiceup;

import android.content.Context;
import android.graphics.Bitmap;
import android.graphics.Canvas;
import android.graphics.Point;
import android.view.KeyEvent;
import android.widget.Toast;

public class Sprite {
      enum State
      {
          Walking, Standing, Jumping
      }
      State mCurrentState = State.Standing;

      Point mDirection;
      int mSpeed = 0;
      Context cc;
      int mPreviousKeyboardState;
    private String spriteName;
    Bitmap sprite;
    private int rows;
    private int rows2;
     int START_POSITION_X = 125;
     int START_POSITION_Y = 245;
     int SPRITE_SPEED = 6;
     int MOVE_UP = -1;
     int MOVE_DOWN = 1;
     int MOVE_LEFT = -1;
     int MOVE_RIGHT = 1;
     Point mStartingPosition;
     int aCurrentKeyboardState;
    private float mScale = 1.0f;
    Point Position;
    public Sprite(String name,Bitmap sprite) {
        this.sprite=sprite;
        this.spriteName=name;
     Position=new Point(150,150);
     mStartingPosition=new Point(150,150);
      mDirection=new Point(0,0);
    }
    public void Update()
    {
        UpdateMovement(aCurrentKeyboardState);
        UpdateJump(aCurrentKeyboardState);


    }
    public void setkeyboard(int keyboard){
         aCurrentKeyboardState = keyboard;
    }
    public void setLastKeyboard(int keyboard){
        mPreviousKeyboardState = keyboard;
   }
    private void UpdateMovement(int aCurrentKeyboardState)
    {
        if (mCurrentState == State.Walking)
        {
            mSpeed = 0;
            mDirection.x = 0;

            if (aCurrentKeyboardState==KeyEvent.KEYCODE_A)
            {
                mSpeed = SPRITE_SPEED;
                mDirection.x = MOVE_LEFT;
            }
            else if(aCurrentKeyboardState==KeyEvent.KEYCODE_D)
            {
                mSpeed = SPRITE_SPEED;
                mDirection.x= MOVE_RIGHT;
            }
            Position.x += mDirection.x * mSpeed;
        }
    }
    private void UpdateJump(int aCurrentKeyboardState)
    {
        if (mCurrentState == State.Walking)
        {
            if (aCurrentKeyboardState==KeyEvent.KEYCODE_SPACE && mPreviousKeyboardState!=KeyEvent.KEYCODE_SPACE)
            {
                Jump();
            }
        }

        if (mCurrentState == State.Jumping)
        {
            if (mStartingPosition.y - Position.y> 150)
            {
                Position.y += mDirection.y * mSpeed;
                mDirection.y = MOVE_DOWN;
            }

            if (Position.y > mStartingPosition.y)
            {
                Position.y = mStartingPosition.y;
                mCurrentState = State.Walking;
            }
        }
    }
    private void Jump()
    {
        if (mCurrentState != State.Jumping)
        {
            mCurrentState = State.Jumping;
            mStartingPosition = Position;
            mDirection.y = MOVE_UP;
            mSpeed = 6;
            Position.y += mDirection.y * mSpeed;
        }
    }
    public void Draw(Canvas c)
    {            
        c.drawBitmap(sprite, Position.x,Position.y, null);
    }
    public void setmCurrentState(State mCurrentState) {
        this.mCurrentState = mCurrentState;
    }
}

這是surfaceview：

import com.example.spiceup.Sprite.State;

import android.content.Context;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.graphics.Canvas;
import android.graphics.Color;
import android.os.Handler;
import android.view.KeyEvent;
import android.view.SurfaceHolder;
import android.view.SurfaceView;

public class GameView extends SurfaceView {
    Context cc;
    Bitmap Sprite;
    Sprite sprite2;
    Handler handlerAnimation100;
    private GameLoopThread gameLoopThread;

    private SurfaceHolder holder;


public GameView(Context c) {
    // TODO Auto-generated constructor stub
super(c);
gameLoopThread = new GameLoopThread(this);
this.cc=c;
this.Sprite=BitmapFactory.decodeResource(getResources(), R.drawable.walk1);
this.Sprite=Bitmap.createScaledBitmap(Sprite, Sprite.getWidth()*2, Sprite.getHeight()*2, false);
sprite2=new Sprite("Spicy",Sprite);
this.requestFocus();
this.setFocusableInTouchMode(true);
holder = getHolder();
holder.addCallback(new SurfaceHolder.Callback() {

       @Override
       public void surfaceDestroyed(SurfaceHolder holder) {
              boolean retry = true;
              gameLoopThread.setRunning(false);
              while (retry) {
                     try {
                           gameLoopThread.join();
                           retry = false;
                     } catch (InterruptedException e) {
                     }
              }
       }

       @Override
       public void surfaceCreated(SurfaceHolder holder) {
              gameLoopThread.setRunning(true);
              gameLoopThread.start();
       }

       @Override
       public void surfaceChanged(SurfaceHolder holder, int format,
                     int width, int height) {
       }
});
}
@Override
protected void onDraw(Canvas canvas) {
    super.onDraw(canvas);
      canvas.drawColor(Color.BLACK);
      sprite2.Update();
sprite2.Draw(canvas);   
}
@Override
public boolean onKeyDown(int keyCode, KeyEvent event) {
    sprite2.setkeyboard(keyCode);
    sprite2.setmCurrentState(State.Walking);
    return false;
}
@Override
public boolean onKeyUp(int keyCode, KeyEvent event) {
       sprite2.setmCurrentState(State.Standing);
       sprite2.setLastKeyboard(keyCode);
    return false;
}
}

如果有人知道我的錯誤在哪里或者有更好的代碼告訴我我會很高興，那么我要做的就是創建一個可以移動並且可以跳躍（但在行走時也可以跳躍）的位圖

Answer 1

所以我認為你的代碼中發生的事情是它在游戲循環中達到了最大高度並且加回到精靈的y。 第二個游戲循環運行它不再高於或接近最大高度距離因此你停止下降並且你的起始位置變成空中的那個位置。 在第三個循環中你再次點擊空格鍵，你的精靈開始整個跳躍過程，同樣的事情發生在下一個循環通過或觸發if語句以使精靈開始下降所需的多少。

開始的好地方是有一個持久的布爾值來確定精靈是否真的完成攀爬和跳躍狀態應該在攀爬和下降時保持真實。 見下文。

boolean maxJumpAchieved = false;
     if (mCurrentState == State.Jumping)
    {
        if (mStartingPosition.y - Position.y> 150)
        {
            maxJumpAchieved = true;
        }
        if (maxJumpAchieved) {
            mDirection.y = MOVE_DOWN;
            Position.y += mDirection.y * mSpeed;
        }
        if (Position.y > mStartingPosition.y)
        {
            maxJumpAchieved = false;
            Position.y = mStartingPosition.y;
            mCurrentState = State.Walking;
        }
    }

我認為這應該為您提供正確的方向，但是如果您遇到問題，請告訴我，我可以編輯答案。

另外需要注意的是不要將mCurrentState設置為State.Walking，直到你確定你已經在地面上，否則你可以連續幾天跳。