网站建设存在风险,莱芜网站设计公司,学校网站建设行业现状,临沂医院手机网站建设ArkTS卡片开放了自定义绘制的能力#xff0c;在卡片上可以通过Canvas组件创建一块画布#xff0c;然后通过CanvasRenderingContext2D对象在画布上进行自定义图形的绘制#xff0c;如下示例代码实现了在画布的中心绘制了一个笑脸。
Entry
Component
struct Card {
private c…ArkTS卡片开放了自定义绘制的能力在卡片上可以通过Canvas组件创建一块画布然后通过CanvasRenderingContext2D对象在画布上进行自定义图形的绘制如下示例代码实现了在画布的中心绘制了一个笑脸。
Entry
Component
struct Card {
private canvasWidth: number 0;
private canvasHeight: number 0;
// 初始化CanvasRenderingContext2D和RenderingContextSettings
private settings: RenderingContextSettings new RenderingContextSettings(true);
private context: CanvasRenderingContext2D new CanvasRenderingContext2D(this.settings);build() {
Column() {
Row() {
Canvas(this.context)
.margin(5%)
.width(90%)
.height(90%)
.onReady(() {
console.info([ArkTSCard] onReady for canvas draw content);
// 在onReady回调中获取画布的实际宽和高
this.canvasWidth this.context.width;
this.canvasHeight this.context.height;
// 绘制画布的背景
this.context.fillStyle rgba(203, 154, 126, 1.00);
this.context.fillRect(0, 0, this.canvasWidth, this.canvasHeight);
// 在画布的中心绘制一个红色的圆
this.context.beginPath();
let radius this.context.width / 3
let circleX this.context.width / 2
let circleY this.context.height / 2
this.context.moveTo(circleX - radius, circleY);
this.context.arc(circleX, circleY, radius, 2 * Math.PI, 0, true);
this.context.closePath();
this.context.fillStyle red;
this.context.fill();
// 绘制笑脸的左眼
let leftR radius / 4
let leftX circleX - (radius / 2)
let leftY circleY - (radius / 3.5)
this.context.beginPath();
this.context.arc(leftX, leftY, leftR, 0, Math.PI, true);
this.context.strokeStyle #ffff00
this.context.lineWidth 10
this.context.stroke()
// 绘制笑脸的右眼
let rightR radius / 4
let rightX circleX (radius / 2)
let rightY circleY - (radius / 3.5)
this.context.beginPath();
this.context.arc(rightX, rightY, rightR, 0, Math.PI, true);
this.context.strokeStyle #ffff00
this.context.lineWidth 10
this.context.stroke()
// 绘制笑脸的嘴巴
let mouthR radius / 2.5
let mouthX circleX
let mouthY circleY (radius / 3)
this.context.beginPath();
this.context.arc(mouthX, mouthY, mouthR, Math.PI, 0, true);
this.context.strokeStyle #ffff00
this.context.lineWidth 10
this.context.stroke()
})
}
}.height(100%).width(100%)
}
}
