Cannot read properties of undefined (reading '_android')

[Cyclodex]

Hi! 👋

Firstly, thanks for your work on this project! 🙂

Today I used patch-package to patch qrcode-js-package@1.0.4 for the project I'm working on.

My issue was, after updating to Vue 2.7.13 and @vue/cli 5.0.8 the generated JS code throws an error, because "this" is undefined when running this line: if (this._android && this._android <= 2.1) {

I think its related to js modules and this is always undefined on global level.

• https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Operators/this?retiredLocale=de#global_context

• 

Here is the diff that solved my problem:

diff --git a/node_modules/qrcode-js-package/qrcode.js b/node_modules/qrcode-js-package/qrcode.js
index f89e602..d5e5bd9 100644
--- a/node_modules/qrcode-js-package/qrcode.js
+++ b/node_modules/qrcode-js-package/qrcode.js
@@ -281,7 +281,7 @@ var QRCode;

        // Android 2.1 bug workaround
        // http://code.google.com/p/android/issues/detail?id=5141
-       if (this._android && this._android <= 2.1) {
+       if (this && this._android && this._android <= 2.1) {
            var factor = 1 / window.devicePixelRatio;
            var drawImage = CanvasRenderingContext2D.prototype.drawImage; 
            CanvasRenderingContext2D.prototype.drawImage = function (image, sx, sy, sw, sh, dx, dy, dw, dh) {

This issue body was partially generated by patch-package.

[Sun-hai-yang]

Have you solved this problem yet？

[Cyclodex]

@Sun-hai-yang What do you mean exactly? The problem can be fixed with the above "patch".

Do you need to know how you can apply it to your own codebase?

[IvanVZabrodin]

For me it still gives the same issue, even after the fix

[hotdogc1017]

I have the same problem as you🥲

[hotdogc1017]

I have found a solution! Replace 'qrcodejs2' with 'qrcodejs2-fix`

in package.json: "qrcodejs2": "^0.0.2", // remove "qrcodejs2-fix": "^0.0.1", // add

[hotdogc1017]

I have found a solution! Replace 'qrcodejs2' with 'qrcodejs2-fix`

in package.json: "qrcodejs2": "^0.0.2", // remove "qrcodejs2-fix": "^0.0.1", // add

I have checked the source code of the error location and the solution is consistent with @Cyclodex proposed method

[Minori-ty]

the same problem