android - 在Ionic App中使用Vega Charts在某些设备上启动时会导致运行时错误

令我非常恼火的是，我发现，我在Android(8.0)手机以及iPhone上成功开发和测试的Ionic 4应用程序卡住在Android(8.1)平板电脑和在iPad上启动时崩溃。通过使用adb logcat诊断技术，我观察到在错误的Android平板电脑上，vendor-es5.js中报告了一个语法错误，当我进入项目的www文件夹并转到错误的引用行时，即SyntaxError: Unexpected token *，我就进入了在明显来自node_modules/d3-delaunay/src/delaunay.js的代码中，并且使用了es6幂运算符**，特别是:

r = 1e-8 * Math.sqrt((bounds[3] - bounds[1])**2 + (bounds[2] - bounds[0])**2);

我不知道为什么此代码在某些设备上会出现问题，也不知道是什么导致了此代码，该代码不是es5(？)不能在未正确编译的情况下出现在vendor-es5.js文件中。为了更进一步，我手动破解了该delaunay.js文件，将所有幂运算实例替换为Math.pow()的等效用法，并且可以肯定的是，运行时间进一步扩大，但最终又在node_modules/vega-dataflow/src/dataflow/load.js和提示SyntaxError: Unexpected token function，特别是在这一行:

export async function request(url, format) {

同样，显然async/await不是es5构造，所以为什么它以vendor-es5.js结尾。在这一点上，我觉得这里有些系统上的错误，而且我没有能力去理解如何克服它，除非切换图形库？我想避免这种情况，所以我的问题是:

为什么会这样？

为什么只对某些设备(而不是所有设备)产生影响？

有没有一种方法可以解决该问题，而无需切换到其他图形库？

更新＃1

因为它是一个Ionic4项目，所以这意味着它是Angular 8项目，这意味着它是一个Webpack项目(与平台的默认设置相同)。所以这是我的angular.json文件:

{
  "$schema": "./node_modules/@angular/cli/lib/config/schema.json",
  "version": 1,
  "defaultProject": "app",
  "newProjectRoot": "projects",
  "projects": {
    "app": {
      "root": "",
      "sourceRoot": "src",
      "projectType": "application",
      "prefix": "app",
      "schematics": {},
      "architect": {
        "build": {
          "builder": "@angular-devkit/build-angular:browser",
          "options": {
            "outputPath": "www",
            "index": "src/index.html",
            "main": "src/main.ts",
            "polyfills": "src/polyfills.ts",
            "tsConfig": "tsconfig.app.json",
            "assets": [
              {
                "glob": "**/*",
                "input": "src/assets",
                "output": "assets"
              },
              {
                "glob": "**/*.svg",
                "input": "node_modules/ionicons/dist/ionicons/svg",
                "output": "./svg"
              }
            ],
            "styles": [
              {
                "input": "src/theme/variables.scss"
              },
              {
                "input": "src/global.scss"
              }
            ],
            "scripts": []
          },
          "configurations": {
            "production": {
              "fileReplacements": [
                {
                  "replace": "src/environments/environment.ts",
                  "with": "src/environments/environment.prod.ts"
                }
              ],
              "optimization": true,
              "outputHashing": "all",
              "sourceMap": false,
              "extractCss": true,
              "namedChunks": false,
              "aot": true,
              "extractLicenses": true,
              "vendorChunk": false,
              "buildOptimizer": true,
              "budgets": [
                {
                  "type": "initial",
                  "maximumWarning": "2mb",
                  "maximumError": "5mb"
                }
              ]
            },
            "ci": {
              "progress": false
            }
          }
        },
        "serve": {
          "builder": "@angular-devkit/build-angular:dev-server",
          "options": {
            "browserTarget": "app:build"
          },
          "configurations": {
            "production": {
              "browserTarget": "app:build:production"
            },
            "ci": {
              "progress": false
            }
          }
        },
        "extract-i18n": {
          "builder": "@angular-devkit/build-angular:extract-i18n",
          "options": {
            "browserTarget": "app:build"
          }
        },
        "test": {
          "builder": "@angular-devkit/build-angular:karma",
          "options": {
            "main": "src/test.ts",
            "polyfills": "src/polyfills.ts",
            "tsConfig": "tsconfig.spec.json",
            "karmaConfig": "karma.conf.js",
            "styles": [],
            "scripts": [],
            "assets": [
              {
                "glob": "favicon.ico",
                "input": "src/",
                "output": "/"
              },
              {
                "glob": "**/*",
                "input": "src/assets",
                "output": "/assets"
              }
            ]
          },
          "configurations": {
            "ci": {
              "progress": false,
              "watch": false
            }
          }
        },
        "lint": {
          "builder": "@angular-devkit/build-angular:tslint",
          "options": {
            "tsConfig": [
              "tsconfig.app.json",
              "tsconfig.spec.json",
              "e2e/tsconfig.json"
            ],
            "exclude": ["**/node_modules/**"]
          }
        },
        "e2e": {
          "builder": "@angular-devkit/build-angular:protractor",
          "options": {
            "protractorConfig": "e2e/protractor.conf.js",
            "devServerTarget": "app:serve"
          },
          "configurations": {
            "production": {
              "devServerTarget": "app:serve:production"
            },
            "ci": {
              "devServerTarget": "app:serve:ci"
            }
          }
        },
        "ionic-cordova-build": {
          "builder": "@ionic/angular-toolkit:cordova-build",
          "options": {
            "browserTarget": "app:build"
          },
          "configurations": {
            "production": {
              "browserTarget": "app:build:production"
            }
          }
        },
        "ionic-cordova-serve": {
          "builder": "@ionic/angular-toolkit:cordova-serve",
          "options": {
            "cordovaBuildTarget": "app:ionic-cordova-build",
            "devServerTarget": "app:serve"
          },
          "configurations": {
            "production": {
              "cordovaBuildTarget": "app:ionic-cordova-build:production",
              "devServerTarget": "app:serve:production"
            }
          }
        }
      }
    }
  },
  "cli": {
    "defaultCollection": "@ionic/angular-toolkit"
  },
  "schematics": {
    "@ionic/angular-toolkit:component": {
      "styleext": "scss"
    },
    "@ionic/angular-toolkit:page": {
      "styleext": "scss"
    }
  }
}

...这是我的package.json文件与项目相关的子集:

{
  "dependencies": {
    "@angular/common": "~8.1.2",
    "@angular/core": "~8.1.2",
    "@angular/forms": "~8.1.2",
    "@angular/http": "^7.2.15",
    "@angular/platform-browser": "~8.1.2",
    "@angular/platform-browser-dynamic": "~8.1.2",
    "@angular/router": "~8.1.2",
    "@ionic-native/core": "^5.15.1",
    "@ionic/angular": "^4.7.1",
    "vega": "~5.6.0",
    "vega-lite": "^3.4.0",
    "vega-themes": "^2.4.0",
    "zone.js": "~0.9.1"
  },
  "devDependencies": {
    "@angular-devkit/architect": "~0.801.2",
    "@angular-devkit/build-angular": "~0.801.2",
    "@angular-devkit/core": "~8.1.2",
    "@angular-devkit/schematics": "~8.1.2",
    "@angular/cli": "~8.1.2",
    "@angular/compiler": "~8.1.2",
    "@angular/compiler-cli": "~8.1.2",
    "@angular/language-service": "~8.1.2",
    "@ionic/angular-toolkit": "~2.0.0",
    "@types/jasmine": "~3.3.8",
    "@types/jasminewd2": "~2.0.3",
    "@types/node": "~8.9.4",
    "codelyzer": "^5.0.0",
    "jasmine-core": "~3.4.0",
    "jasmine-spec-reporter": "~4.2.1",
    "karma": "~4.1.0",
    "karma-chrome-launcher": "~2.2.0",
    "karma-coverage-istanbul-reporter": "~2.0.1",
    "karma-jasmine": "~2.0.1",
    "karma-jasmine-html-reporter": "^1.4.0",
    "protractor": "~5.4.0",
    "ts-node": "~7.0.0",
    "tslint": "~5.15.0",
    "typescript": "~3.4.3"
  }
}

更新＃2

继续尝试解决这个问题，我对package.json进行了以下更新:

  "dependences":
    "tslib": added => "^1.10.0"
    "vega": "~5.6.0" => "^5.9.0"
    "vega-lite": "^3.4.0" => "^4.0.2"

  "devDependencies":
    "@angular/compiler": "~8.1.2" => "~8.2.9"
    "@angular/compiler-cli": "~8.1.2" => "~8.2.9"
    "typescript": "~3.4.3" => "~3.5.3"

...经过这些更改，我认为我在www/vendor-es5.js文件中得到了明显的es5编译输出，而我的adb logcat结果似乎没有表明语法错误。不幸的是，该应用程序仍然无法通过“启动画面”(再次，仅在某些设备上是这种情况)。

这是我来自项目的tsconfig.json文件:

{
  "compileOnSave": false,
  "compilerOptions": {
    "baseUrl": "./",
    "outDir": "./dist/out-tsc",
    "sourceMap": true,
    "declaration": false,
    "module": "esnext",
    "moduleResolution": "node",
    "emitDecoratorMetadata": true,
    "experimentalDecorators": true,
    "importHelpers": true,
    "target": "es2015",
    "typeRoots": [
      "node_modules/@types"
    ],
    "lib": [
      "es2018",
      "dom"
    ]
  },
  "angularCompilerOptions": {
    "fullTemplateTypeCheck": true,
    "strictInjectionParameters": true
  }
}

...就vega的使用而言，关键是:

    const theme = vega.fivethirtyeight;
    this._view = new vega.View(vega.parse(vegaSpec, theme), {})
      .initialize(this.container.nativeElement)
      .logLevel(vega.Warn)
      .renderer('svg');

...在有问题的设备上，如果我将adb logcat输出过滤到E(错误)行，则会看到以下内容:

01-10 09:17:27.650  6413  6413 E ApkAssets: Error while loading asset assets/natives_blob_64.bin: java.io.FileNotFoundException: assets/natives_blob_64.bin
01-10 09:17:27.651  6413  6413 E ApkAssets: Error while loading asset assets/snapshot_blob_64.bin: java.io.FileNotFoundException: assets/snapshot_blob_64.bin
01-10 09:17:27.680  6413  6413 E         : appName=xxxxxx, acAppName=/system/bin/surfaceflinger
01-10 09:17:27.680  6413  6413 E         : 0
01-10 09:17:27.683  6413  6413 E         : appName=xxxxxx, acAppName=vStudio.Android.Camera360
01-10 09:17:27.683  6413  6413 E         : 0
01-10 09:17:27.781  6413  6413 E MPlugin : Unsupported class: com.mediatek.common.telephony.IOnlyOwnerSimSupport
01-10 09:17:28.153  6413  6464 E libEGL  : validate_display:99 error 3008 (EGL_BAD_DISPLAY)
01-10 09:17:28.432  6413  6464 E         : appName=xxxxxx, acAppName=vStudio.Android.Camera360
01-10 09:17:28.433  6413  6464 E         : 0
01-10 09:17:28.436  6413  6464 E         : appName=xxxxxx, acAppName=vStudio.Android.Camera360
01-10 09:17:28.436  6413  6464 E         : 0
01-10 09:17:28.437  6413  6464 E         : appName=xxxxxx, acAppName=vStudio.Android.Camera360
01-10 09:17:28.437  6413  6464 E         : 0
01-10 09:17:30.514  6413  6455 E         : appName=xxxxxx, acAppName=vStudio.Android.Camera360
01-10 09:17:30.514  6413  6455 E         : 0
01-10 09:17:30.515  6413  6455 E         : app

...并且在很大程度上，这是W(警告)行:

01-10 09:17:27.835  6413  6413 W chromium: [WARNING:password_handler.cc(33)] create-->contents = 0x9c66ec00, delegate = 0xa4b7edd0
01-10 09:17:27.835  6413  6413 W chromium: [WARNING:password_handler.cc(41)] attaching to web_contents
01-10 09:17:27.837  6413  6413 W cr_AwContents: onDetachedFromWindow called when already detached. Ignoring
01-10 09:17:28.185  6413  6455 W libEGL  : [ANDROID_RECORDABLE] format: 1
01-10 09:17:28.209  6413  6464 W VideoCapabilities: Unrecognized profile/level 1/32 for video/mp4v-es
01-10 09:17:28.209  6413  6464 W VideoCapabilities: Unrecognized profile/level 32768/2 for video/mp4v-es
01-10 09:17:28.209  6413  6464 W VideoCapabilities: Unrecognized profile/level 32768/64 for video/mp4v-es
01-10 09:17:28.244  6413  6455 W libEGL  : [ANDROID_RECORDABLE] format: 1
01-10 09:17:28.248  6413  6464 W VideoCapabilities: Unsupported mime video/x-ms-wmv
01-10 09:17:28.253  6413  6464 W VideoCapabilities: Unsupported mime video/divx
01-10 09:17:28.262  6413  6464 W VideoCapabilities: Unsupported mime video/xvid
01-10 09:17:28.268  6413  6464 W VideoCapabilities: Unsupported mime video/flv1
01-10 09:17:28.274  6413  6464 W VideoCapabilities: Unrecognized profile/level 1/32 for video/mp4v-es
01-10 09:17:28.485  6413  6413 W cr_BindingManager: Cannot call determinedVisibility() - never saw a connection for the pid: 6413
01-10 09:17:28.568  6413  6413 W cr_BindingManager: Cannot call determinedVisibility() - never saw a connection for the pid: 6413

最佳答案

首先，我想说这确实是vega包错误-我认为这是通过npm传递未转译代码的一种不好的方法。例如Angular Package Format保证您将获得es5有效代码(如果需要)。但是vega并不是一个明确的angular依赖项，因此让我们解决它。

为什么会这样呢？

因为有些开发人员以es6+标准提供软件包，所以在需要es5兼容应用程序之前是可以的。在我看来，库开发人员应该构建并交付es5和es6 bundle ，否则对于他们的用户来说将是一个头痛的事情(例如您的vega案例)。

为什么它只对某些设备(而不是所有设备)产生影响？

老实说，我在原生移动开发方面的经验非常有限-我在这里只能说，例如，移动Chrome和台式机Chrome在引擎方面存在一些差异。这意味着不能保证使用相同的软件将提供相同的结果。有时，您可以在移动浏览器中找到该错误，而无法在 table 面浏览器中重现该错误。

我认为在您的情况下，某些带有某些浏览器引擎的设备可以使用es6代码-有些则不能。
同样在您的问题的第一个版本中有useragent字符串-我认为高级移动开发人员可以说比我更多的使用。

有没有一种方法可以解决该问题而无需切换到其他图形库？

是的。
我创建了一个repo，其设置与您的设置非常相似-基于ionic@4的简单angular@8项目。

现在，您的 bundle 是es5和es6混合在一起的。让我们完全兼容es5以使其在任何浏览器中都可以工作(即使在ie11中，我也测试了该项目)。
完成工作的步骤:

安装依赖项。我们将在进一步的步骤中需要它们。

npm i -S regenerator-runtime
npm i -D @angular-builders/custom-webpack babel-loader @babel/core @babel/preset-env

将target中的es5属性更改为tsconfig。 "target": "es5"

我们将转换async/await，因此我们需要将regenerator-runtime polyfill作为polyfills.ts添加到import 'regenerator-runtime/runtime'

主要步骤。更改angular.json中的构建器，并添加webpack.config.js的路径以对build和serve使用自定义Webpack配置:

       "build": {
          "builder": "@angular-builders/custom-webpack:browser",
          "options": {
            "customWebpackConfig": {
                 "path": "./webpack.config.js"
              },
...
        "serve": {
          "builder": "@angular-builders/custom-webpack:dev-server",

在根文件夹中创建webpack.config.js，其中包含用于转换vega及其依赖项的规则。我以非常必要的方式找到了它们。

// these dependencies are es6!!!
const transpileList = ['node_modules/vega', 'node_modules/d3', 'node_modules/delaunator'];

module.exports = function(base) {
    return {
        ...base,
        module: {
            ...base.module,
            rules: [
                ...base.module.rules,
                {
                    test: function(fileName) {
                        return transpileList.some(name => fileName.includes(name)) && fileName.endsWith('.js');
                    },
                    use: {
                        loader: 'babel-loader',
                        options: {
                            presets: ['@babel/preset-env']
                        }
                    }
                }
            ]
        }
    }
}

完成这些步骤后，希望您的应用程序可以在任何es5环境中运行。我尝试使用默认的三星浏览器在台式机ie11和平板电脑Samsung A中进行尝试。

关于android - 在Ionic App中使用Vega Charts在某些设备上启动时会导致运行时错误，我们在Stack Overflow上找到一个类似的问题：https://stackoverflow.com/questions/59606443/