对当前的WebView设置下载监听
mCurrentWebView.setDownloadListener(new DownloadListener() {
@Override
public void onDownloadStart(final String url, String userAgent, String contentDisposition, String mimetype, long contentLength) {
// TODO 实现下载逻辑
Log.e("onDownloadStart", "url===" + url + "---userAgent=" + userAgent + "---contentDisposition=" + contentDisposition + "---mimetype=" + mimetype + "---contentLength=" + contentLength);
}
});
下载文件核心代码:
HttpParams params = new BasicHttpParams();
HttpConnectionParams.setConnectionTimeout(params, 5 * 1000);
HttpConnectionParams.setSoTimeout(params, 5 * 1000);
HttpGet httpGet = new HttpGet(url); try {
File file = new File(Environment.getExternalStorageDirectory(), fileName);
if (!file.exists()) {
file.createNewFile();
} else {
boolean flag = file.delete();
if (flag) {
file.createNewFile();
} else {
return;
}
} RandomAccessFile randomFile = new RandomAccessFile(file, "rw"); HttpResponse response = new DefaultHttpClient(params).execute(httpGet);
HttpEntity entity = response.getEntity(); InputStream in = entity.getContent();
randomFile.seek(randomFile.length()); byte[] buffer = new byte[1024];
int lenght = 0;
while ((lenght = in.read(buffer)) > 0) {
randomFile.write(buffer, 0, lenght);
DebugTraceTool.debugTraceE(this, "file length == " + randomFile.length());
}
randomFile.close();
httpGet.abort(); } catch (Exception e) {
e.printStackTrace();
}
需要注意的点:
1.需要单启动一个线程,不能在主线程执行文件下载的操作.
2.下载的文件名,长度有限制,推荐文件的名称的长度控制在100.防止出现IOException: open failed: ENAMETOOLONG (File name too long)错误,导致下载的任务无法正常开始. 原因: Java语言规范中对文件名的长度是没有限制的。但是操作系统对文件名的长度有限制,最常见的是255个字节,这个限制长度包括文件名的后缀,如.mp3,.mkv等。