微信小程序海報分享方案

previewImage預覽能加載臨時路徑的圖片嗎

//適配不一樣屏幕大小的canvas

setCanvasSize: function () {

var size = {};

try {

var res = wx.getSystemInfoSync();

var scale = 750 / 686;//不一樣屏幕下canvas的適配比例；設計稿是750寬

var width = res.windowWidth / scale;

var height = width;//canvas畫布爲正方形

size.w = width;

size.h = height;

} catch (e) {

// Do something when catch error

}

return size;

},

createQrCode: function (url, canvasId, cavW, cavH) {

//調用插件中的draw方法，繪製二維碼圖片

QR.qrApi.draw(url, canvasId, cavW, cavH);

var that = this;

//二維碼生成以後調用canvasToTempImage();延遲1s，不然獲取圖片路徑爲空

var st = setTimeout(function () {

that.canvasToTempImage();

clearTimeout(st);

}, 1000);



},

//獲取臨時緩存照片路徑，存入data中

canvasToTempImage: function () {

var that = this;

wx.canvasToTempFilePath({

canvasId: 'mycanvas',

success: function (res) {

var tempFilePath = res.tempFilePath;

that.setData({

imagePath: tempFilePath,

});

},

fail: function (res) {

}

});

}, index: function () {

wx.reLaunch({

url: '../../pages/index/index'

})

}

,

//點擊圖片進行預覽，長按保存分享圖片

previewImg: function (e) {

var img = this.data.imagePath

console.log(this.data.imagePath)

wx.previewImage({

current: img, // 當前顯示圖片的http連接

urls: [img] // 須要預覽的圖片http連接列表

})

// console.log(img)



}