如何从 webview 中的按钮启动相机 -Android
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【中文标题】如何从 webview 中的按钮启动相机 -Android【英文标题】：How to launch camera from button in webview -Android 【发布时间】：2014-03-07 16:13:25 【问题描述】：如何通过 Web 视图中的按钮启动设备的摄像头？
我在 android 中有这段代码：
protected void onCreate(Bundle savedInstanceState)
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
webview = (WebView)findViewById(R.id.webView1);
webview.getSettings().setjavascriptEnabled(true);
webview.loadUrl("file:///android_asset/camtest.html");
而且Html文件很简单：
<html>
<body>
<form enctype="multipart/form-data" method="post">
<h2>capture=camera</h2>
<input type="file" accept="image/*;capture=camera"></input>
</form>
</body>
</html>
当我启动应用程序并单击按钮时，
日志显示：
02-10 12:00:03.775: V/WebViewInputDispatcher(10110): blockWebkitDraw
02-10 12:00:03.775: V/WebViewInputDispatcher(10110): blockWebkitDraw lockedfalse
02-10 12:00:04.085: D/webview(10110): blockWebkitViewMessage= false
而且相机没有启动。
我错过了什么？
【问题讨论】：
通过 html 无法启动相机。您必须使用 phonegap lib 或类似的东西。或者您必须编写自己的 JavascriptInterface 来访问相机。 @Shudy 【参考方案1】：你可以使用Phonegap
将活动扩展到DroidGap
然后在assets folder 内创建文件夹www
并在文件夹www 内创建文件夹js 并在其中放置phonegap.js
然后创建文件index.html:
<!DOCTYPE html>
<html>
<head>
<title>Capture Photo</title>
<meta name="viewport" content="width=device-width,height=device-height,initial-scale=1"/>
<script type="text/javascript" charset="utf-8" src="js/phonegap.js"></script>
<script type="text/javascript" charset="utf-8">
var pictureSource; // picture source
var destinationType; // sets the format of returned value
// Wait for PhoneGap to connect with the device
//
document.addEventListener("deviceready",onDeviceReady,false);
// PhoneGap is ready to be used!
//
function onDeviceReady()
pictureSource=navigator.camera.PictureSourceType;
destinationType=navigator.camera.DestinationType;
// Called when a photo is successfully retrieved
//
function onPhotoDataSuccess(imageData)
// Get image handle
//
var smallImage = document.getElementById('smallImage');
// Unhide image elements
//
smallImage.style.display = 'block';
// Show the captured photo
// The inline CSS rules are used to resize the image
//
smallImage.src = "data:image/jpeg;base64," + imageData;
// Called when a photo is successfully retrieved
//
function onPhotoFileSuccess(imageData)
// Get image handle
console.log(JSON.stringify(imageData));
// Get image handle
//
var smallImage = document.getElementById('smallImage');
// Unhide image elements
//
smallImage.style.display = 'block';
// Show the captured photo
// The inline CSS rules are used to resize the image
//
smallImage.src = imageData;
// Called when a photo is successfully retrieved
//
function onPhotoURISuccess(imageURI)
// Uncomment to view the image file URI
// console.log(imageURI);
// Get image handle
//
var largeImage = document.getElementById('largeImage');
// Unhide image elements
//
largeImage.style.display = 'block';
// Show the captured photo
// The inline CSS rules are used to resize the image
//
largeImage.src = imageURI;
// A button will call this function
//
function capturePhotoWithData()
// Take picture using device camera and retrieve image as base64-encoded string
navigator.camera.getPicture(onPhotoDataSuccess, onFail, quality: 50 );
function capturePhotoWithFile()
navigator.camera.getPicture(onPhotoFileSuccess, onFail, quality: 50, destinationType: Camera.DestinationType.FILE_URI );
// A button will call this function
//
function getPhoto(source)
// Retrieve image file location from specified source
navigator.camera.getPicture(onPhotoURISuccess, onFail, quality: 50,
destinationType: destinationType.FILE_URI,
sourceType: source );
// Called if something bad happens.
//
function onFail(message)
alert('Failed because: ' + message);
</script>
</head>
<body>
<button onclick="capturePhotoWithData();">Capture Photo With Image Data</button> <br>
<button onclick="capturePhotoWithFile();">Capture Photo With Image File URI</button> <br>
<button onclick="getPhoto(pictureSource.PHOTOLIBRARY);">From Photo Library</button><br>
<button onclick="getPhoto(pictureSource.SAVEDPHOTOALBUM);">From Photo Album</button><br>
<img style="display:none;width:60px;height:60px;" id="smallImage" src="" />
<img style="display:none;" id="largeImage" src="" />
</body>
</html>
然后你必须添加库cordova.jar
然后运行你的应用程序
【讨论】：
在哪里可以找到“cordova.jar”文件？以上是关于如何从 webview 中的按钮启动相机 -Android的主要内容，如果未能解决你的问题，请参考以下文章