fohow_xcx/pages/activity/screen/screen.js

var _request = require('../../../utils/request.js')
var canvas = {}
var width = 0
var height = 0
var ctx
var img
var imgInfo = {}
var touchX = 0
var touchY = 0
var ix = 50
var iy = 200
Page({
  data: {
  },
  onLoad: function (options) {
    var info = wx.getSystemInfoSync()
    console.log(info)
    width = info.windowWidth
    height = info.windowHeight
    ctx = wx.createCanvasContext('myCanvas')
    this.draw()
    ctx.draw()
  },
  draw: function () {
    ctx.save()
    ctx.setFillStyle('#0b0b0b')
    ctx.setFontSize(this.dpi(28))
    ctx.fillText('明明什么都没有做', this.dpi(75), this.dpi(42))
    ctx.setFontSize(this.dpi(26))
    ctx.fillText('就已经', this.dpi(35), this.dpi(120))
    ctx.fillText('了', this.dpi(275), this.dpi(120))
    ctx.restore()
  },
  dpi: function (val) {
    return val * width / 375
  },
  ming: function () {
    wx.navigateTo({
      url: '/pages/start/start'
    })
  },
  shang: function () {
    var that = this
    wx.chooseImage({
      count: 1,
      success: function (val) {
        console.log(val)
        img = val.tempFilePaths[0]
        that.chooseImage()
      }
    })
  },
  chooseImage: function (val) {
    var that = this
    wx.getImageInfo({
      src: img,
      success: function (res) {
        console.log(res)
        imgInfo = res
        that.drawImage()
      }
    })
    // ctx.drawImage(sx, sy, sWidth, sHeight, dx, dy, dWidth, dHeight)
  },
  drawImage: function () {
    var w = 275
    var h = w * imgInfo.height / imgInfo.width
    console.log(h)
    console.log(img)
    console.log(String(h))
    ctx.drawImage(String(img), this.dpi(ix), this.dpi(iy), this.dpi(w), this.dpi(h))
    this.draw()
    ctx.draw()
  },
  save: function () {
    var that = this
    wx.canvasToTempFilePath({
      destWidth: width * 2,
      destHeight: height * 2,
      canvasId: 'myCanvas',
      fileType: 'jpg',
      success: function (res) {
        that.saveImage(res.tempFilePath)
      }
    })
  },
  saveImage: function (val) {
    wx.saveImageToPhotosAlbum({
      filePath: val,
      success(res) {
        wx.showToast({
          title: '已保存相册',
          icon: 'success',
          duration: 2000
        })
      }
    })
  },
  move: function (res) {
    console.log(res)
    if (img) {
      if (res.touches.length === 1) {
        var x = res.touches[0].x - touchX
        var y = res.touches[0].y - touchY
        ix = ix + x
        iy = iy + y
        touchX = res.touches[0].x
        touchY = res.touches[0].y
        this.drawImage()
      }
    }
  },
  start: function (val) {
    touchX = val.changedTouches[0].x
    touchY = val.changedTouches[0].y
  },
  onShareAppMessage: function (val) {
    if (val.from === 'button') {
    }
    return {
      title: '"明明什么都没有做"壁纸生成工具',
      path: '/pages/activity/screen/screen',
      imageUrl: 'https://fohow.oss-cn-shenzhen.aliyuncs.com/xcx/share/mingming.jpg',
      success: function(res) {
      },
      fail: function(res) {
      }
    }
  },
})