<template>
<canvas type="2d" v-if="isUseNewCanvas" class="ec-canvas" :canvas-id="canvasId" @init="init" @touchstart="touchStart"
@touchmove="touchMove" @touchend="touchEnd">
</canvas>
<canvas v-else class="ec-canvas" :canvas-id="canvasId" @init="init" @touchstart="touchStart" @touchmove="touchMove"
@touchend="touchEnd">
</canvas>
</template>
<script>
import WxCanvas from "./wx-canvas";
import * as echarts from "./echarts";
let ctx;
function wrapTouch(event) {
for (let i = 0; i < event.touches.length; ++i) {
const touch = event.touches[i];
touch.offsetX = touch.x;
touch.offsetY = touch.y;
}
return event;
}
export default {
props: {
canvasId: {
type: String,
default: () => {
return "ec-canvas";
}
},
ec: {
type: Object
},
forceUseOldCanvas: {
type: Boolean,
value: false
}
},
data() {
return {
$curChart: {},
toHandleList: [],
isUseNewCanvas: true
};
},
watch: {
"ec.option": {
deep: true,
handler(val, oldVal) {
this.setOption(val);
}
}
},
onReady: function() {
if (!this.ec) {
console.warn(
'组件需绑定 ec 变量，例：<ec-canvas id="mychart-dom-bar" ' +
'canvas-id="mychart-bar" ec="{{ ec }}"></ec-canvas>'
);
return;
}
if (!this.ec.lazyLoad) {
this.init();
}
},
methods: {
compareVersion(v1, v2) {
v1 = v1.split(".");
v2 = v2.split(".");
const len = Math.max(v1.length, v2.length);
while (v1.length < len) {
v1.push("0");
}
while (v2.length < len) {
v2.push("0");
}
for (let i = 0; i < len; i++) {
const num1 = parseInt(v1[i]);
const num2 = parseInt(v2[i]);
if (num1 > num2) {
return 1;
} else if (num1 < num2) {
return -1;
}
}
return 0;
},
init(callback) {
const version = wx.getSystemInfoSync().SDKVersion;
let canUseNewCanvas = this.compareVersion(version, "2.9.0") >= 0;
if (this.forceUseOldCanvas) {
if (canUseNewCanvas) console.warn("开发者强制使用旧canvas,建议关闭");
canUseNewCanvas = false;
}
this.isUseNewCanvas = canUseNewCanvas && !this.forceUseOldCanvas;
if (this.isUseNewCanvas) {
console.log('微信基础库版本大于2.9.0，开始使用<canvas type="2d"/>');
// 2.9.0 可以使用 <canvas type="2d"></canvas>
this.initByNewWay(callback);
} else {
const isValid = this.compareVersion(version, "1.9.91") >= 0;
if (!isValid) {
console.error(
"微信基础库版本过低，需大于等于 1.9.91。" +
"参见：https://github.com/ecomfe/echarts-for-weixin" +
"#%E5%BE%AE%E4%BF%A1%E7%89%88%E6%9C%AC%E8%A6%81%E6%B1%82"
);
return;
} else {
console.warn(
"建议将微信基础库调整大于等于2.9.0版本。升级后绘图将有更好性能"
);
this.initByOldWay(callback);
}
}
},
initByOldWay(callback) {
// 1.9.91 <= version < 2.9.0：原来的方式初始化
ctx = wx.createCanvasContext(this.canvasId, this);
const canvas = new WxCanvas(ctx, this.canvasId, false);
const that = this
echarts.setCanvasCreator(() => {
return canvas;
});
// const canvasDpr = wx.getSystemInfoSync().pixelRatio // 微信旧的canvas不能传入dpr
const canvasDpr = 1;
var query = wx.createSelectorQuery().in(this);
query
.select(".ec-canvas")
.boundingClientRect(res => {
if (typeof callback === "function") {
that.$curChart = callback(canvas, res.width, res.height, canvasDpr);
} else if (that.ec) {
that.initChart(canvas, res.width, res.height, canvasDpr)
} else {
that.triggerEvent("init", {
canvas: canvas,
width: res.width,
height: res.height,
devicePixelRatio: canvasDpr // 增加了dpr，可方便外面echarts.init
});
}
})
.exec();
},
initByNewWay(callback) {
const that = this
// version >= 2.9.0：使用新的方式初始化
const query = wx.createSelectorQuery().in(this);
query
.select(".ec-canvas")
.fields({
node: true,
size: true
})
.exec(res => {
const canvasNode = res[0].node;
const canvasDpr = wx.getSystemInfoSync().pixelRatio;
const canvasWidth = res[0].width;
const canvasHeight = res[0].height;
const ctx = canvasNode.getContext("2d");
const canvas = new WxCanvas(ctx, that.canvasId, true, canvasNode);
echarts.setCanvasCreator(() => {
return canvas;
});
if (typeof callback === "function") {
that.$curChart = callback(
canvas,
canvasWidth,
canvasHeight,
canvasDpr
);
} else if (that.ec) {
that.initChart(canvas, canvasWidth, canvasHeight, canvasDpr)
} else {
that.triggerEvent("init", {
canvas: canvas,
width: canvasWidth,
height: canvasHeight,
devicePixelRatio: canvasDpr
});
}
});
},
setOption(val) {
if (!this.$curChart || !this.$curChart.setOption) {
this.toHandleList.push(val);
} else {
this.$curChart.setOption(val);
}
},
canvasToTempFilePath(opt) {
if (this.isUseNewCanvas) {
// 新版
const query = wx.createSelectorQuery().in(this);
query
.select(".ec-canvas")
.fields({
node: true,
size: true
})
.exec(res => {
const canvasNode = res[0].node;
opt.canvas = canvasNode;
wx.canvasToTempFilePath(opt);
});
} else {
// 旧的
if (!opt.canvasId) {
opt.canvasId = this.canvasId;
}
ctx.draw(true, () => {
wx.canvasToTempFilePath(opt, this);
});
}
},
touchStart(e) {
if (this.ec.stopTouchEvent) {
e.preventDefault();
e.stopPropagation();
return;
}
this.$emit("touchstart", e);
if (this.$curChart && e.touches.length > 0) {
var touch = e.touches[0];
var handler = this.$curChart.getZr().handler;
if (handler) {
handler.dispatch("mousedown", {
zrX: touch.x,
zrY: touch.y
});
handler.dispatch("mousemove", {
zrX: touch.x,
zrY: touch.y
});
handler.processGesture(wrapTouch(e), "start");
}
}
},
touchMove(e) {
if (this.ec.stopTouchEvent) {
e.preventDefault();
e.stopPropagation();
return;
}
this.$emit("touchmove", e);
if (this.$curChart && e.touches.length > 0) {
var touch = e.touches[0];
var handler = this.$curChart.getZr().handler;
if (handler) {
handler.dispatch("mousemove", {
zrX: touch.x,
zrY: touch.y
});
handler.processGesture(wrapTouch(e), "change");
}
}
},
touchEnd(e) {
if (this.ec.stopTouchEvent) {
e.preventDefault();
e.stopPropagation();
return;
}
this.$emit("touchend", e);
if (this.$curChart) {
const touch = e.changedTouches ? e.changedTouches[0] : {};
var handler = this.$curChart.getZr().handler;
if (handler) {
handler.dispatch("mouseup", {
zrX: touch.x,
zrY: touch.y
});
handler.dispatch("click", {
zrX: touch.x,
zrY: touch.y
});
handler.processGesture(wrapTouch(e), "end");
}
}
},
initChart(canvas, width, height, canvasDpr) {
this.$curChart = echarts.init(canvas, null, {
width: width,
height: height,
devicePixelRatio: canvasDpr
});
canvas.setChart(this.$curChart);
this.$curChart.setOption(this.ec.option);
}
}
};
</script>
<style lang="scss">
.ec-canvas {
width: 100%;
height: 100%;
display: block;
}
</style>