cordova - How to find out what is causing my white screen of death? -
i have ionic app. it's works couple of weeks, stops. splash screen followed white screen of death. when debug using chrome://inspect app following message in console:
no content-security-policy meta tag found. please add 1 when using cordova-plugin-whitelist plugin.
if clear data on app, starts working, , same message when debug working app on device, don't think it's plugin @ fault. however, have used plugin explore white-screen problem, because can white screen of death if add following index.html (a content security policy prevents loading resources source):
<meta http-equiv="content-security-policy" content="default-src 'none'"> when that, error messages in console:
refused load stylesheet 'file:///android_asset/www/lib/ionic/css/ionic.min.css' because violates following content security policy directive: "default-src 'none'". note 'style-src' not explicitly set, 'default-src' used fallback
and when change tag this:
<meta http-equiv="content-security-policy" content="default-src 'self'"> i in console:
refused apply inline style because violates the..etc
and
evalerror: refused evaluate string javascript because 'unsafe-eval' not allowed source of script...etc"
but now, instead of white screen, exception handler catching problem , reporting it.
from this, deduce absence of files causes white screen, because exception handler works if files loaded.
i can rid of errors in console using security policy:
<meta http-equiv="content-security-policy" content="style-src 'self' ionic.bundle.min.js 'unsafe-inline'; script-src 'self' console-via-logger.js 'unsafe-eval'; img-src 'self' ionic.bundle.min.js data:"> so wondering if there way catch exception in application @ earlier stage can diagnose original white-screen problem? think must in data preventing file being loaded, how be?
to test kerri shotts theory javascript error getting in way of app startup, added throw app.js file:
(function () { 'use strict'; throw ('test'); //setting dependencies var app = angular.module('app', [..etc..] ]); })(); sure enough - white screen of death
next added window.onerror script index.html:
<body data-ng-app="app"> <script> (function () { window.onerror = function (errormsg, url, linenumber, column, errorobj) { alert('error: ' + errormsg + ' script: ' + url + ' line: ' + linenumber + ' column: ' + column + ' stacktrace: ' + errorobj); } }()); </script> ....etc i had add 'unsafe-inline' content security policy script run, once did got alert error message instead of white screen.
my csp:
<meta http-equiv="content-security-policy" content="style-src 'self' ionic.bundle.min.js 'unsafe-inline'; script-src 'self' console-via-logger.js 'unsafe-eval' 'unsafe-inline'; img-src 'self' ionic.bundle.min.js data:">
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