Resizing a Cordova WebView on Click Event of PhoneGap Plugin in iOS: A Step-by-Step Guide

Resizing a Cordova WebView on Click Event of PhoneGap Plugin in iOS

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In this article, we will explore how to resize a Cordova WebView when a user clicks on a button created within the WebView. We’ll dive into the world of Cordova plugins, native code integration, and iOS-specific details.

Introduction

Cordova, also known as PhoneGap, is a popular framework for building hybrid mobile applications using web technologies such as HTML, CSS, and JavaScript. One of its key features is the ability to integrate native plugins, allowing developers to access device hardware and perform tasks that are not possible with standard web technologies.

In this article, we’ll focus on resizing a Cordova WebView when a user clicks on a button created within it. This requires creating a custom plugin, writing native code for iOS, and understanding how the WebView interacts with its parent view controller.

Prerequisites

Before diving into the details, make sure you have:

Cordova (version 10.x or later) installed on your system.
Xcode (version 12.5 or later) installed on your system.
Basic knowledge of web technologies, JavaScript, and HTML/CSS.

Creating a Custom Cordova Plugin

To resize the WebView, we need to create a custom plugin that will handle the logic for resizing the view. Here’s how you can do it:

Step 1: Create the plugin

Create a new folder in your project directory called cordova-plugin-webview-resize. Inside this folder, create the following files:

index.js: This file contains the main logic of our plugin.
plugin.xml: This file defines metadata for our plugin.

index.js

/**
 * @name cordova-plugin-webview-resize
 * @namespace plugins.webview-resize
 */

exports.plugin = {
    // Name of the plugin
    name: 'cordova-plugin-webview-resize',
    
    // Version number
    version: '1.0.0',
    
    // Web views to be observed for resizing
    webViews: ['WebView'],
    
    // Register the native module
    register: function (platform) {
        platform.registerNativesForPlugin('cordova-plugin-webview-resize', {
            WebViewResize: function (thisView, options) {
                this.resize(thisView);
            },
            
            // Native methods
            resize: function (thisView) {
                let x = options.x;
                let y = options.y;
                let width = options.width;
                let height = options.height;
                
                // Get the view frame
                var rect = thisView.frame;
                
                // Resize the view
                if (rect != null) {
                    thisView.view.setFrame(rect);
                }
            },
        });
    }
};

plugin.xml

<?xml version="1.0" encoding="utf-8"?>
<plugin xmlns="http://apache.org/cordova/ns/plugins/1.0"
         id="cordova-plugin-webview-resize"
         version="1.0.0">
    <name>cordova-plugin-webview-resize</name>
    <description>Resize Cordova WebView on click event of PhoneGap plugin in iOS.</description>
    <platform name="ios"></platform>
    
    <feature name="WebView">
        <platform name="ios"></platform>
        
        <!-- Native methods -->
        <method name="resize" />
    </feature>
</plugin>

Step 2: Add the plugin to your Cordova project

To add the plugin to your Cordova project, run the following command in your terminal:

cordova plugin add cordova-plugin-webview-resize

Integrating the Plugin with PhoneGap

Next, we need to integrate our plugin with PhoneGap. Create a new JavaScript file called main.js and add the following code:

main.js

// Get the current web view
var webView = document.querySelector('div[contenteditable="true"]');

// Set up the plugin
cordova.plugins.WebViewResize WebViewResize = {
    // Set the x coordinate
    x: 0,
    
    // Set the y coordinate
    y: 0,
    
    // Set the width
    width: 100,
    
    // Set the height
    height: 100,
};

// Add an event listener for clicks on the web view
webView.addEventListener('click', function () {
    WebViewResize.resize({
        x: this.clientX,
        y: this.clientY,
        width: WebViewResize.width,
        height: WebViewResize.height,
    });
});

Creating a Button in the Cordova WebView

Next, we need to create a button within our WebView. Add the following code to your index.html file:

<!-- Create the web view -->
<div id="webView" contenteditable="true">
    <!-- Create the button -->
    <button onclick="handleButtonClick()">Click me!</button>
</div>

<script>
    // Function to handle button clicks
    function handleButtonClick() {
        document.querySelector('div#webView').click();
    }
</script>

Resizing the Cordova WebView

Finally, we need to resize our WebView when the user clicks on the button. Add the following code to your main.js file:

// Function to handle resizing of the web view
function handleResize(width, height) {
    // Resize the web view
    document.querySelector('div#webView').style.width = width + 'px';
    document.querySelector('div#webView').style.height = height + 'px';
}

// Set up event listener for resize notifications from plugin
cordova.plugins.WebViewResize.addEventListener('resize', function (e) {
    handleResize(e.detail.width, e.detail.height);
});

Conclusion

In this article, we’ve covered how to resize a Cordova WebView when a user clicks on a button created within it. We created a custom plugin that handles the logic for resizing the view and integrated it with PhoneGap.

We also demonstrated how to create a button within our WebView, add an event listener for clicks on the web view, and handle resizing of the web view when the user clicks on the button.

By following this tutorial, you should now have a basic understanding of how to resize a Cordova WebView using a custom plugin. Happy coding!

Last modified on 2023-11-14