我可以让Android的WebView支持其他图像格式（如TIFF）？ [英] Can I make Android WebView support other image formats (e.g. TIFF)?
问题描述
例如，如何使以下的HTML页面实际显示图像，在Android的WebView？
For example, how to make the following HTML page actually display the image, in an Android WebView?
<html>
<body>
<img src="http://www.alternatiff.com/sample.tif">
</body>
</html>
任意（黑客）的建议是AP preciated。我只是一个应用程序开发者和无法控制整个系统，所以修改操作系统源$ C $ c是不适用的。
Any (hacking) suggestion is appreciated. I am only an app developer and cannot control the whole system, so modifying the OS source code is not applicable.
推荐答案
我还没有试过，但是这是我会做什么：
I haven't tried this, but this is what I would do:
- 请的一个子类
WebViewClient - 覆盖
shouldInterceptRequest（）查询的网址，看是否请求了TIFF。如果它不是一个TIFF，返回空来告诉的WebView来处理该请求本身。 - 如果请求了TIFF，打开
HttpURLConnection类来的TIFF URL和读取数据时，TIFF转换为JPEG或PNG的ex。如何TIFF转换成JPEG / PNG在Java 并成立了一个的InputStream来读取JPEG / PNG图像的字节数。 - 返回一个
WebResourceResponse的MIME类型（即图像/ JPEG格式），的InputStream创建阅读图像数据。 - 呼叫
setWebViewClient与你的WebViewClient子类的实例web视图。
- Make a subclass of
WebViewClient - Override
shouldInterceptRequest()to check the URL and see if a TIFF was requested. If it was not a TIFF, returnnullto tell theWebViewto handle the request itself. - If a TIFF was requested, open
HttpURLConnectionto the TIFF url and read the data, convert the TIFF to a JPEG or PNG ex. How to convert TIFF to JPEG/PNG in java and set up anInputStreamto read the JPEG/PNG image bytes. - Return a
WebResourceResponsewith the mime type (i.e. image/jpeg) and theInputStreamyou created to read the image data. - Call
setWebViewClienton the webview with an instance of yourWebViewClientsubclass.
而不是使用JNI库设备上的转换，我想我会的图像转换的服务器上，并打开HttpURLConnection类为pre转换的图像流，即<一个href=\"http://example.com/convert_tiff?url=http%3A%2F%2Fwww.alternatiff.com%2Fsample.tif&fmt=JPEG\" rel=\"nofollow\">http://example.com/convert_tiff?url=http%3A%2F%2Fwww.alternatiff.com%2Fsample.tif&fmt=JPEG然后返回的InputStream 在 WebResourceResponse 。我想这取决于带宽和服务器资源多么便宜的为您服务。
Rather than converting on the device using a JNI library, I think I would convert the image on a server and open the HttpURLConnection to the pre-converted image stream, i.e. http://example.com/convert_tiff?url=http%3A%2F%2Fwww.alternatiff.com%2Fsample.tif&fmt=JPEG and then return that InputStream in the WebResourceResponse. I guess it depends on how cheap the bandwidth and server resources are for you.
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