Add errorCallback option

README.md

@@ -159,12 +159,12 @@ easyMDE.value('New input for **EasyMDE**');
     - **sbProgress**: Status message displayed to show uploading progress. Defaults to `Uploading #file_name#: #progress#%`.
     - **sbOnUploaded**: Status message displayed when the image has been uploaded. Defaults to `Uploaded #image_name#`.
     - **sizeUnits**: A comma-separated list of units used to display messages with human-readable file sizes. Defaults to `b,Kb,Mb`.
-- **errorMessages**: Errors displayed to the user, mainly on alert popups, where `#image_name#`, `#image_size#` and `#image_max_size#` will replaced by their respective values, that can be used for customization or internationalization:
+- **errorMessages**: Errors displayed to the user, using the `errorCallback` option, where `#image_name#`, `#image_size#` and `#image_max_size#` will replaced by their respective values, that can be used for customization or internationalization:
     - **noFileGiven**: The server did not receive any file from the user. Defaults to `You must select a file.`.
     - **imageTypeNotAllowed**: The user send a file type which doesn't match the `imageAccept` list, or the server returned this error code. Defaults to `This image type is not allowed.`.
     - **imageTooLarge**: The size of the image being imported is bigger than the `imageMaxSize`, or if the server returned this error code. Defaults to `Image #image_name# is too big (#image_size#).\nMaximum file size is #image_max_size#.`.
     - **imageImportError**: An unexpected error occurred when uploading the image. Defaults to `Something went wrong when uploading the image #image_name#.`.
-
+- **errorCallback**: A callback function used to define how to display an error message. Defaults to `function(errorMessage) {alert(errorMessage);};`.
 - **renderingConfig**: Adjust settings for parsing the Markdown during previewing (not editing).
   - **codeSyntaxHighlighting**: If set to `true`, will highlight using [highlight.js](https://github.com/isagalaev/highlight.js). Defaults to `false`. To use this feature you must include highlight.js on your page or pass in using the `hljs` option. For example, include the script and the CSS files like:<br>`<script src="https://cdn.jsdelivr.net/highlight.js/latest/highlight.min.js"></script>`<br>`<link rel="stylesheet" href="https://cdn.jsdelivr.net/highlight.js/latest/styles/github.min.css">`
   - **hljs**: An injectible instance of [highlight.js](https://github.com/isagalaev/highlight.js). If you don't want to rely on the global namespace (`window.hljs`), you can provide an instance here. Defaults to `undefined`.

src/js/easymde.js

@@ -1426,7 +1426,7 @@ var imageTexts = {
 };
 
 /**
- * Errors displayed to the user, mainly on alert popups. Can be used for
+ * Errors displayed to the user, using the `errorCallback` option. Can be used for
  * customization or internationalization.
  */
 var errorMessages = {
@@ -1547,6 +1547,9 @@ function EasyMDE(options) {
 
     options.minHeight = options.minHeight || '300px';
 
+    options.errorCallback = options.errorCallback || function(errorMessage) {
+      alert(errorMessage);
+    };
 
     // Import-image default configuration
     options.uploadImage = options.uploadImage || false;
@@ -1621,7 +1624,7 @@ EasyMDE.prototype.uploadImages = function(files) {
         this.uploadImage(files[i], function onSuccess(imageUrl) {
             afterImageUploaded(self, imageUrl);
         }, function onFailure(error) {
-            alert(error);
+            self.options.errorCallback(error);
         });
     }
     this.updateStatusBar('upload-image', self.options.imageTexts.sbOnDrop.replace('#images_names#', names.join(', ')));
@@ -1831,22 +1834,22 @@ EasyMDE.prototype.autosave = function () {
             console.log('EasyMDE: You must set a uniqueId to use the autosave feature');
             return;
         }
-        
+
         if(this.options.autosave.binded !== true) {
           if (easyMDE.element.form != null && easyMDE.element.form != undefined) {
               easyMDE.element.form.addEventListener('submit', function () {
                   clearTimeout(easyMDE.autosaveTimeoutId);
                   easyMDE.autosaveTimeoutId = undefined;
-                
+
                   localStorage.removeItem('smde_' + easyMDE.options.autosave.uniqueId);
-                  
+
                   // Restart autosaving in case the submit will be cancelled down the line
                   setTimeout(function() {
                     easyMDE.autosave();
                   }, easyMDE.options.autosave.delay || 10000);
               });
           }
-          
+
           this.options.autosave.binded = true;
         }