1. WebView allows Android applications to display HTML, JavaScript and CSS content. It provides a bridge that allows JavaScript code to interact with Java code in the Android app. 2. JavaScript code can call Java methods and Java code can call JavaScript functions through the bridge provided by WebView. 3. Images can be encoded to base64 strings in Java code and displayed in HTML content loaded in WebView, avoiding separate network requests.

1. HTML
Android
maruyama-r

2. • WebView HTML/JavaScript/CSS
HTML/JavaScript/CSS
WebView :
WebView
Android Framework
Linux

3. JavaScript Java
• Java
public class JavaScriptInterface {
public String getString(){
return "Hello";
}
}
....
jsInterface = new JavaScriptInterface();
webView.addJavascriptInterface(jsInterface, “API”);
• JavaScript
var msg = API.getString();

4. Java JavaScript
• Java
webView.loadUrl(“javascript:putString(‘Bye’)”);
• JavaScript
function putString(msg){
document.write(msg);
}

6. (´ ω )

8. ( ∀ )

11. 1. JavaScript Java
2. Bitmap
3. Bitmap PNG
4. PNG Base64
5. URI
6. JavaScript

12. URI
• img src
<img src="data:image/
png;base64,iVBORw0KGgoAAAANSUhEUgAAAAUA
AAAFCAYAAACNbyblAAAAHElEQVQI12P4//8/
w38GIAXDIBKE0DHxgljNBAAO
9TXL0Y4OHwAAAABJRU5ErkJggg==" alt="Red
dot" />
http://en.wikipedia.org/wiki/Data_URI_scheme

13. URI
• 4/3
• HTTP
• CSS background-image CSS

14. • img onload
• SharedPreferences Android
• Android2.1 Base64
•