Get selected text in Safari and use it in action extension

Question

I'm making an action extension for safari and I need to get the selected text for use inside the extension.

Usually in iOS i use this code to get the selected text in a webview

selectedText.text = [WebView stringByEvaluatingJavaScriptFromString: @ "window.getSelection (). toString ()"];

But inside the extension i don't know how can I do !

For completeness it should be an extension with IU and i've just to turn on NSExtensionActivationSupportsWebURLWithMaxCount to make extension available in Safari.

Thanks in advance

Answer 1

As Apple explains in their App Extension Programming Guide, you need to include a JavaScript file in the extension to perform any preprocessing. The results of that preprocessing are available via NSExtensionItem in the extension.

A simple example of this file is included in my iOS Extension Demo project at GitHub and looks like this:

var MyPreprocessor = function() {};

MyPreprocessor.prototype = {
    run: function(arguments) {
        arguments.completionFunction({"URL": document.URL, "pageSource": document.documentElement.outerHTML, "title": document.title, "selection": window.getSelection().toString()});
    }
};

var ExtensionPreprocessingJS = new MyPreprocessor;

That simply extracts various details about the current page and passes them to completionFunction. The ExtensionPreprocessingJS var at the end is the hook that the extension framework looks for.

In the extension you can retrieve these values in a dictionary by asking for an item of type kUTTypePropertyList:

for (NSExtensionItem *item in self.extensionContext.inputItems) {
    for (NSItemProvider *itemProvider in item.attachments) {
        if ([itemProvider hasItemConformingToTypeIdentifier:(NSString *)kUTTypePropertyList]) {
            [itemProvider loadItemForTypeIdentifier:(NSString *)kUTTypePropertyList options:nil completionHandler:^(NSDictionary *jsDict, NSError *error) {
                dispatch_async(dispatch_get_main_queue(), ^{
                    NSDictionary *jsPreprocessingResults = jsDict[NSExtensionJavaScriptPreprocessingResultsKey];
                    // Continue with data returned from JS...