How to convert div containing an image into a png in Ionic/Angular

You can do this by installing the html2canvas library via `npm i html2canvas`
But you have to remember to useCORS if your div includes an externally located image! very important.

html2canvas(this.screen.nativeElement, {
      useCORS: true, //By passing this option in function Cross origin images will be rendered properly in the downloaded version of the PDF
    }).then(canvas => {
      this.canvas.nativeElement.src = canvas.toDataURL();
      this.downloadLink.nativeElement.href = canvas.toDataURL('image/png'); = new Date() + '.png';;

Implement App Tracking Transparency for Ionic Angular and Cordova iOS app

How to use the plugin in Ionic v3.

I had some issues using the example provided so I had to call the exec directly:

// first install the plugin
// cordova plugin add cordova-plugin-idfa
// npm i cordova-plugin-idfa --save

// add permissions to config.xml under ios platform
<platform name="ios">
    <edit-config target="NSUserTrackingUsageDescription" file="*-Info.plist" mode="merge">
        <string> My tracking usage description </string>

// has to be called after platform is ready
// this.platform.ready().then(() => {}

askTrackingPermission() {
    if ('cordova') &&'ios')) {

      if (window.cordova) {
        console.log('trying to request permission ');
        window.cordova.exec(win, fail, 'idfa', "requestPermission", []);

    function win(res) {
      console.log('success ' + JSON.stringify(res));
    function fail(res) {
      console.log('fail ' + JSON.stringify(res));

readTrackingPermission() {

    if ('cordova') &&'ios')) {

      if (window.cordova) {
        window.cordova.exec(win, fail, 'idfa', "getInfo", []);

    function win(res) {
      console.log('success  ' + JSON.stringify(res));
    function fail(res) {
      console.log('fail ' + JSON.stringify(res));

Also, you can only test this from the iOS simulator (or device) running 14.5.1+ iOS. In your iOS device settings check privacy->tracking (setting) it has to be allowed to ask. And you will only be able to ask the user once.

Good luck!

How to Open PDF/File in Ionic on Android

How to Open PDF/File in Ionic on Android?

If you recently tried to open a file in Ionic from the application dir using `fileOpener2` plugin you may have encountered an error `File Not Found` which could indicate permission error.

It turns out you can’t open a file from `applicationDirectory` directly, you have to copy it into another directory:

if ('android')) {
  const self = this;
  const targetFile = self.file.dataDirectory + '/' + yourFileName;
  self.file.copyFile(self.file.applicationDirectory + 'www/assets/', yourFileName, 
                     self.file.dataDirectory, yourFileName).
           then(function (res) {, 'application/pdf');

Install the Cordova Plugin here:

How To Create Downloadable CSV File in JS/Angular

import { SecurityContext } from '@angular/core';
import { DomSanitizer } from '@angular/platform-browser';
private sanitizer: DomSanitizer;

downloadCSV() {

  let blob = new Blob([yourdata], { type: 'text/csv' });
  let urlPath = this.sanitizer.sanitize(SecurityContext.URL,
  let tempLink = document.createElement('a');
  tempLink.href = urlPath;
  tempLink.setAttribute('download', 'download.csv');;

Google Android Play Store Target API Requirement Change

From Google:

Hello Google Play Developer,

This is a reminder that starting November 1, 2019, updates to apps and games on Google Play will be required to target Android 9 (API level 28) or higher. After this date, the Play Console will prevent you from submitting new APKs with a targetSdkVersion less than 28.

Configuring your app to target a recent API level ensures that users benefit from significant security and performance improvements, while still allowing your app to run on older Android versions (down to the minSdkVersion).

Android 9 (API level 28) introduces a number of changes to the Android system. The following behavior changes apply exclusively to apps that are targeting API level 28 or higher. Apps that set targetSdkVersion to API level 28 or higher must modify their apps to support these behaviors properly, where applicable to the app.

To target the api in your Cordova app set these min and target version in config.xml

    <preference name="android-minSdkVersion" value="23" />
    <preference name="android-targetSdkVersion" value="28" />

iOS Deprecated API Usage Warning Ionic using UIWebView

Apple will no longer support web apps that use UIWebView. The apps and libraries need to be migrated to use WkWebView.

The latest Ionic already uses WkWebView, but several Cordova plugins still rely on UIWebView which is a problem.

If you’re using Ionic you need to upgrade to iOS Cordova 5

cordova platform remove ios
cordova platform add ios@5.0.0

Also you might need to remove additional plugins that use UIWebView such as inappbrowser.

cordova plugin rm cordova-plugin-inappbrowser

More information about the breaking changes can be found here:

How to Enable Preflight CORS in PHP for Angular HTTP requests

When testing Ionic or Angular app you might need to set CORS policy to access a service on a different domain. One way to do this in PHP for testing is to send OK responses for all OPTIONS requests. (If you are testing POST and GET requests)

In your php file set:

// change to your app origin
header('Access-Control-Allow-Origin: http://localhost:8100');
header ("Access-Control-Expose-Headers: Content-Length, X-JSON");
header ("Access-Control-Allow-Methods: GET, POST, PATCH, PUT, DELETE, OPTIONS");
header ("Access-Control-Allow-Headers: Content-Type, Authorization, Accept, Accept-Language, X-Authorization");
header('Access-Control-Max-Age: 86400');

    // The request is using the POST method
    header("HTTP/1.1 200 OK");


Don’t ship this test code, this is just for your internal testing of http requests.

How to mask and unmask input element password type in Ionic / Angluar

How to mask and unmask input element password type in ionic/angular/js:

this.togglePasswordField = function () {
     console.log("toggle password field called");
     if (document.getElementById("passwordElement").type == "password") {
        document.getElementById("passwordElement").type = "text";

     else {
          document.getElementById("passwordElement").type = "password";

This way only uses basic html element manipulation.

passwordHideIcon element is a button that calls the function and uses the ionic icon for eyes and eyes disabled.

How to Disable Android Back Button in Ionic 1 / Angular

To disable back button in Android put one of the codes below in your app.js in the .run function.

// app.js

// Disable Back in Entire App
}, 100);

Or Conditionally Disable Back:

// app.js

  if($ionicHistory.currentStateName === 'someStateName'){
}, 100);

How To Build Production and Release Version of Ionic App

To make the production and release version of Android app using Ionic run:

ionic cordova build ios --prod --release

This should run the same as the expanded version:

ionic cordova build ios --minifycss --optimizejs --minifyjs --release

You may need to run with sudo in front of the command if you have permission issues.

For iOS builds the –release flag does not seem to do anything in my testing. I could not find any official documentation explaining what this flag does to iOS builds.

For more detail visit the ionic documentation on building

JS Infinite Alert Prank Code gets Japanese Girl in Serious Trouble

Ars Technica Reporting:

Explaining her actions, the girl said that she’d run into such pranks herself and thought it would be funny if someone clicked the link.

The Twitter user referenced in the message, 0_Infinity_, has a protected account, but the user left a message in their bio field suggesting that they don’t understand why there’s so much fuss about the script today, as it was written in 2014.

To protest the actions of the Japanese police and the absurdity of calling this act a crime, Tokyo developer Kimikazu Kato has published on GitHub a project called Let’s Get Arrested. Forking the project and then creating a branch named gh-pages will create a simple GitHub-hosted website that contains nothing but the infinitely looped alert, putting criminality at our fingertips.

for ( ; ; ) {
    window.alert(" ∧_∧ ババババ\n( ・ω・)=つ≡つ\n(っ ≡つ=つ\n`/  )\n(ノΠU\n何回閉じても無駄ですよ~ww\nm9(^Д^)プギャー!!\n byソル (@0_Infinity_)")

Calling her a criminal is totally absurd.

Creating and Opening PDF on Ionic 1 on iOS

Recently I ran into an issue using the PdfMake on Ionic 1 on iOS. It works fine on the browser with a simple download or open command but not on the actual device.

Install the cordova libraries:


Download the pdfmake javascript files and include them in your index.html

<script src='build/pdfmake.min.js'></script>
<script src='build/vfs_fonts.js'></script>

The code:

  var self = this ; // defined on top of the file

  var docDefinition = { content: 'This is an sample PDF printed with pdfMake' };

            self.pdfObj = pdfMake.createPdf(docDefinition);

            if (window.cordova) {
                self.pdfObj.getBuffer(function (buffer) {
                    var blob = new Blob([buffer], { type: 'application/pdf' });
                    // Save the PDF to the data Directory of our App
                    $cordovaFile.writeFile(cordova.file.dataDirectory, 'myletter.pdf', blob, { replace: true }).then(function () {
                        // Open the PDf with the correct OS tools
               + 'myletter.pdf', 'application/pdf');

Setup Config.xml

In your config.xml make sure you have the file settings

<preference name="AndroidPersistentFileLocation" value="Compatibility" />
<preference name="iosPersistentFileLocation" value="Library" />