你想反馈一个 Bug 还是 提一个需求？
Bug
如果是 Bug：
* Bug 表现是什么？预期表现是什么？
iOS 真机中调试面板中报错
undefined is not an object (evaluating 'e.canvasId')
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* 如何复现？
在 Component 中使用 canvas 绘图，移除组件后报错。
* 提供一个最简复现 Demo
Page({
data: {
show: true,
},
handleToggle() {
this.setData({ show: !this.data.show });
},
});
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{
"navigationBarTitleText": "canvasId error",
"usingComponents": {
"custom-component": "./custom-component/custom-component"
}
}
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<!-- canvas-id-error.wxml -->
<block wx:if="{{show}}">
<custom-component></custom-component>
</block>
<button bindtap="handleToggle">Toggle canvas</button>
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/* canvas-id-error.wxss */
custom-component {
width: 750rpx;
height: 750rpx;
display: block;
}
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Component({
attached() {
this.canvasContext = wx.createCanvasContext('my-canvas-id', this);
this._render();
},
detached() {
this.canvasContext = null;
},
methods: {
_render() {
if (!this.canvasContext) {
return;
}
const ctx = this.canvasContext;
ctx.moveTo(10, 10);
ctx.lineTo(100, 10);
ctx.lineTo(100, 100);
ctx.fill();
ctx.draw();
},
},
});
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<!-- custom-component/custom-component.wxml -->
<canvas canvas-id="my-canvas-id"></canvas>
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/* custom-component/custom-component.wxss */
canvas {
width: 750rpx;
height: 750rpx;
display: block;
}
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