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| == Introduction to Android WebView ==
| | {{Migrating|https://smartpossdk.gitbook.io/cloudpossdk/faq/firmware/update-pos-webview}} |
| Android WebView is an important system component on the Android platform that allows Android apps to embed HTML page content and browse websites directly within the app. It uses the Blink rendering engine from Chrome to display webpage content and allows developers to package and distribute webpages as native apps.
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| The main functions of Android WebView include:
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| * Loading and displaying webpage content written in HTML, CSS, and JavaScript within an Android app.
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| * Supporting common webpage elements and features such as images, videos, audio, tables, forms, etc.
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| * Providing rich APIs for interactions between JavaScript and Java.
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| * Caching webpage content and user data to improve access speed and user experience.
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| Android WebView has become an essential part of many Android apps, particularly in e-commerce, social networking, news, and other fields.
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| WebView is often used in Android development to display web content or web applications within an application, mainly for the following reasons:
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| * Unified interface experience: The web content displayed through WebView can match the UI interface of the native application, improving the user experience.
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| * Convenient update and maintenance: Unlike native applications that require publishing a new version to update features, web content in WebView can be updated via the server.
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| * Reuse existing Web technology stack: For companies or individual developers who have invested heavily in frontend resources, they can reuse their existing frontend technology stack to reduce development costs.
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| In short, WebView can serve as a powerful supplement to native applications under certain scenarios, allowing applications to fully leverage the advantages of Web technologies.
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| WebView is commonly used in various scenarios in Android development, including:
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| * In-app browsing: Displaying external website content within an application, providing users with a seamless browsing experience without leaving the application.
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| * Hybrid apps: Combining native app functionality with web content to create hybrid apps, which can provide better performance than traditional web-based apps while still leveraging the benefits of web technologies.
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| * Single-page applications (SPA): Building single-page applications within a WebView, allowing for faster loading times and smoother user interactions compared to loading multiple pages.
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| * Webviews in widgets: Using WebViews to display dynamic content in home screen widgets, such as weather updates or news headlines.
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| Overall, WebView is a versatile tool that can be utilized in a wide range of use cases in Android development, depending on the specific needs and requirements of each project.
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| Here is an example code snippet demonstrating how to use a WebView:
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| <syntaxhighlight lang="java">
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| // Create a new WebView object
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| WebView webView = new WebView(this);
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| // Set the layout parameters for the WebView
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| webView.setLayoutParams(new ViewGroup.LayoutParams(ViewGroup.LayoutParams.MATCH_PARENT,
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| ViewGroup.LayoutParams.MATCH_PARENT));
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| // Load the specified URL into the WebView
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| webView.loadUrl("https://www.example.com");
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| // Add the WebView to the layout
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| ((ViewGroup) findViewById(R.id.activity_main)).addView(webView);
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| </syntaxhighlight>
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| The above code creates a new WebView object and sets its layout parameters so that it fills the entire screen. We then call the loadUrl() method to load the specified URL into the WebView and add the WebView object to the layout.
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| Additionally, if you need to handle JavaScript events inside the web page, you can set a WebViewClient and/or a WebChromeClient for the WebView:
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| <syntaxhighlight lang="java">
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| webView.setWebViewClient(new WebViewClient() {
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| @Override
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| public boolean shouldOverrideUrlLoading(WebView view, String url) {
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| // Handle URL navigation events here
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| return super.shouldOverrideUrlLoading(view, url);
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| }
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| });
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| webView.setWebChromeClient(new WebChromeClient());
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| </syntaxhighlight>
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| In this code, we set a new WebViewClient instance and override the shouldOverrideUrlLoading() method to handle URL navigation events. We also set a new WebChromeClient instance to handle other interactive events inside the web page, such as JavaScript dialog boxes.
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| Note that these examples demonstrate basic usage of the WebView. Depending on the requirements of your project, you may need to implement additional functionality, such as handling network errors or caching web content.
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| == Update System WebView ==
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| Android WebView is a native component provided by the operating system, and upgrading to a higher version requires installation of a WebView signed by the system signature to succeed. Customers may provide their preferred versions（ download the latest version of WebView from the Google Developer website (https://developers.google.com/android/guides/webview) ） for review and signing by us, or select from several signed versions offered by us to attempt installation.
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| Please note that updating the system WebView involves modifying the device's operating system, which can be risky and void warranties.
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| Note that the version of the system WebView is dependent on the Android OS version running on POS. Some older devices may not support the latest version of the WebView.
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| Another alternative is to use a third-party WebView library, such as Crosswalk, which includes its own version of the WebView component that you can integrate into your application. This way, you can bypass the limitations imposed by the system WebView and have more control over the WebView version used in your app. However, keep in mind that using a third-party library may increase your app size and could potentially introduce stability issues.
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| == WebView versions in different model==
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| * Q2: version is 74
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| == WebView with system signature==
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| [http://ftp.wizarpos.com/webview/com.android.webview_102.0.5005.96-q2_releasekey.apk webview version 102 download]
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