taro 小程序画布海报保存图片

川长思鸟来 2023-01-13 01:45 250阅读 0赞

import Taro, { Component, Config } from '@tarojs/taro'
    import './index.scss'
    import { View } from '@tarojs/components'
    
    
    type S = {
        member?: MemberVO,
        scan: boolean,
    }
    
    export default class UserHome extends Taro.Component<any, S> {
    
        state: S = {
            scan: false,
        }
    
    
        config: Config = {
            navigationBarTitleText: '推广我的'
        };
    
        constructor(props) {
            super(props)
            this.state = {
                imageTempPath: ''
            }
        }
        componentWillMount(): void {
            this.drawBall()
        }
        drawBall() {
            const context = Taro.createCanvasContext('canvas', this)
            const imgPath1 = '/h5/dist/static/img/loroto.2abbee7.png';
            const imgPath2 = m/h5/dist/static/img/loroto.2abbee7.png';
            const _this = this;
            Taro.getImageInfo({
                src: imgPath1,
            }).then((res) => {
                context.drawImage(res.path, 0, 0, 375, 667);
                Taro.getImageInfo({
                    src: imgPath2,
                }).then((res2) => {
                    context.drawImage(res2.path, 250, 195, 86, 86);
                    const h = _this.fillTextWrap(context, '【润百颜玻尿酸】告别黄脸婆，一百这白丑', 20, 230, 190, 20);
                    context.font = 'normal 11px ArialMT sans-serif';
                    context.setFontSize(16);
                    context.setFillStyle('#FF6066');
                    context.fillText('￥66', 40, 290);
                    context.font = 'normal 11px  PingFangSC-Regular sans-serif';
                    context.setFontSize(12);
                    context.setFillStyle('#FA2E9A');
                    context.fillText('扫描小程序码查看', 245, 300);
                    context.draw(false, () => {
                        Taro.canvasToTempFilePath({
                            canvasId: 'canvas',
                            success: function (res) {
                                // 获得图片临时路径
                                _this.setState({
                                    imageTempPath: res.tempFilePath
                                })
                            }
                        })
                    });
                });
            });
        }
    
        saveImage() {
            // 查看是否授权
            Taro.getSetting({
                complete() {
                    console.log(444)
                }
            }).then(res => {
                if (res.authSetting['scope.writePhotosAlbum']) {
                    Taro.saveImageToPhotosAlbum({
                        filePath: this.state.imageTempPath
                    }).then(res => {
                        console.log(res)
                    })
                } else {
                    Taro.authorize({
                        scope: 'scope.writePhotosAlbum',
                    }).then(() => {
                        Taro.saveImageToPhotosAlbum({
                            filePath: this.state.imageTempPath
                        }).then(res => {
                            console.log(res)
                        })
                    })
                }
            }).catch((e) => {
                console.log(e)
            })
        }
        // 文字换行
        fillTextWrap(ctx, text, x, y, maxWidth, lineHeight) {
            // 设定默认最大宽度
            const systemInfo = Taro.getSystemInfoSync();
            const deciveWidth = systemInfo.screenWidth;
            // 默认参数
            maxWidth = maxWidth || deciveWidth;
            lineHeight = lineHeight || 20;
            // 校验参数
            if (typeof text !== 'string' || typeof x !== 'number' || typeof y !== 'number') {
                return;
            }
            // 字符串分割为数组
            const arrText = text.split('');
            // 当前字符串及宽度
            let currentText = '';
            let currentWidth;
            ctx.font = 'normal 11px sans-serif';
            ctx.setFontSize(16);
            ctx.setFillStyle('#3A3A3A');
            ctx.setTextAlign('justify');
            for (let letter of arrText) {
                currentText += letter;
                currentWidth = ctx.measureText(currentText).width;
                if (currentWidth > maxWidth) {
                    ctx.fillText(currentText, x, y);
                    currentText = '';
                    y += lineHeight;
                }
            }
            if (currentText) {
                ctx.fillText(currentText, x, y);
            }
        }
    
    
    
    
        render() {
            // console.log(this.state, 'this.state')
            // const { member, scan } = this.state;
            return (
            
                <View className="datter">
                    <canvas style="width: 375px; height: 600px;background:#fff" canvas-id="canvas"></canvas>
                    <View className='btn btn-pink save-image' onClick={this.saveImage.bind(this)}>保存图片</View>
    
                </View>
            );
        }
    }