用抖音开发者工具开发坦克大战小游戏，显示完整代码

抖音开发者工具是一款专门用于开发小程序的工具，如果要开发坦克大战小游戏，需要先了解一些小程序开发的基础知识。下面是一个简单的坦克大战小游戏的示例代码：

1. wxml文件：

<view class="container">
  <canvas canvas-id="myCanvas" class="canvas"></canvas>
  <view class="btn-group">
    <button class="btn" bindtap="moveUp">上</button>
    <button class="btn" bindtap="moveLeft">左</button>
    <button class="btn" bindtap="moveRight">右</button>
    <button class="btn" bindtap="moveDown">下</button>
    <button class="btn" bindtap="fire">开火</button>
  </view>
</view>

2. wxss文件：

.container {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  height: 100vh;
}

.canvas {
  width: 300px;
  height: 300px;
  background-color: #eee;
  margin-bottom: 10px;
}

.btn-group {
  display: flex;
  justify-content: center;
}

.btn {
  margin: 0 10px;
  padding: 10px;
  font-size: 16px;
  border-radius: 5px;
  background-color: #f60;
  color: #fff;
}

3. js文件：

const tankImg = 'tank.png'; // 坦克图片地址
const bulletImg = 'bullet.png'; // 子弹图片地址
const tankSize = 50; // 坦克大小
const bulletSize = 10; // 子弹大小
const moveStep = 5; // 移动步长

let ctx, canvasWidth, canvasHeight;
let tank, bullet;
let moveDirection = ''; // 移动方向

Page({
  onReady() {
    // 获取canvas上下文
    const query = wx.createSelectorQuery();
    query.select('#myCanvas').fields({ node: true, size: true }).exec((res) => {
      const canvas = res[0].node;
      ctx = canvas.getContext('2d');
      canvasWidth = res[0].width;
      canvasHeight = res[0].height;

      // 加载坦克和子弹图片
      tank = new Image();
      tank.src = tankImg;
      bullet = new Image();
      bullet.src = bulletImg;

      // 绘制坦克
      tank.onload = () => {
        ctx.drawImage(tank, canvasWidth / 2 - tankSize / 2, canvasHeight / 2 - tankSize / 2, tankSize, tankSize);
      }

      // 定时绘制
      setInterval(() => {
        ctx.clearRect(0, 0, canvasWidth, canvasHeight);
        drawTank();
        drawBullet();
      }, 20);
    });
  },

  moveUp() {
    moveDirection = 'up';
  },

  moveLeft() {
    moveDirection = 'left';
  },

  moveRight() {
    moveDirection = 'right';
  },

  moveDown() {
    moveDirection = 'down';
  },

  fire() {
    // TODO 发射子弹
  }
});

function drawTank() {
  switch (moveDirection) {
    case 'up':
      if (tank.offsetTop > 0) {
        tank.style.top = `${tank.offsetTop - moveStep}px`;
      }
      break;
    case 'left':
      if (tank.offsetLeft > 0) {
        tank.style.left = `${tank.offsetLeft - moveStep}px`;
      }
      break;
    case 'right':
      if (tank.offsetLeft < canvasWidth - tankSize) {
        tank.style.left = `${tank.offsetLeft + moveStep}px`;
      }
      break;
    case 'down':
      if (tank.offsetTop < canvasHeight - tankSize) {
        tank.style.top = `${tank.offsetTop + moveStep}px`;
      }
      break;
  }
  ctx.drawImage(tank, tank.offsetLeft, tank.offsetTop, tankSize, tankSize);
}

function drawBullet() {
  // TODO 绘制子弹
}

这是一个简单的示例代码，仅供参考。具体的实现需要根据实际需求进行修改和完善。