点击R G B改变view颜色

<!--components/test/test.wxml-->
<view style="background-color:rgb({{fullColor}});" class="colorBox">颜色值：{{fullColor}}</view>
<button size="mini" type="default" bindtap="changeR">R</button>
<button size="mini" type="primary" bindtap="changeG">G</button>
<button size="mini" type="warn" bindtap="changeB">B</button>
<!-- <view>{{rgb.r}},{{rgb.g}},{{rgb.b}}</view> -->

// components/test/test.js
Component({
  properties: {

  },
  data: {
    rgb:{
      r:0,
      g:0,
      b:0
    },
    fullColor:'0, 0, 0'
  },
  observers:{
    'rgb.r,rgb.g,rgb.b':function(r,g,b){
      this.setData({
        fullColor:`${r}, ${g}, ${b}`
      })
    }
    // 'rgb.**':function(obj){
    //   this.setData({
    //     fullColor:`${obj.r}, ${obj.g}, ${obj.b}`
    //   })
    // }
  },
  methods: {
    changeR() {
      this.setData({
        'rgb.r': this.data.rgb.r + 5 > 255 ? 255 : this.data.rgb.r + 5
      })
    },
    changeG() {
      this.setData({
        'rgb.g': this.data.rgb.g + 5 > 255 ? 255 : this.data.rgb.g + 5
      })
    },
    changeB() {
      this.setData({
        'rgb.b': this.data.rgb.b  + 5 > 255 ? 255 : this.data.rgb.b + 5
      })
    }
  }
})

/* components/test/test.wxss */
.colorBox{
  line-height: 200rpx;
  font-size: 24rpx;
  color: white;
  text-shadow: 0rpx 0rpx 2rpx black;
  text-align: center;
}

app.json中全局引用

  "usingComponents": {
    "my-test":"/components/test/test"
  }

组件使用：

<!--pages/home/home.wxml-->
<my-test></my-test>