Android Volley扩展实现支持进度条的文件上传功能
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2022-07-04 09:46:39
volley是一个轻量级的开源网络通信框架,开源的好处就是可以*定制自己需要的jar包。volley里网络通信时android2.3以上用的httpurlconnecti...
volley是一个轻量级的开源网络通信框架,开源的好处就是可以*定制自己需要的jar包。volley里网络通信时android2.3以上用的httpurlconnection,2.3以下用的httpclient,我做的改动只考虑了2.3以上,不支持2.3版本以下。httpurlconnection默认传输数据是将数据全部写到内存中再发送到服务端,volley就是采用默认的方式,这样在上传大文件时很容易就out of memory,有一种解决办法是设置每次传输流的大小:
已知文件大小:connection .setfixedlengthstreamingmode(long l);
不知道文件大小:connection.setchunkedstreamingmode(1024); //建议使用
android的文件上传一般都是模拟表单,也可以直接socket传,我这里是集成了表单上传,下面是关键类:
public class multipartrequest extends request<string> { private final listener<string> mlistener; private map<string, string> headermap; private map<string, string> mparams; private formfile[] files; private string boundary = "---------7dc05dba8f3e19"; public multipartrequest(string url, listener<string> listener, map<string, string> params, formfile[] files) { this(method.post, url, listener, params, files); } public multipartrequest(int method, string url, listener<string> listener, map<string, string> params, formfile[] files) { super(method, url, listener); mlistener = listener; mparams = params; this.files = files; } @override public map<string, string> getheaders() throws authfailureerror { headermap = new hashmap<string, string>(); headermap.put("charset", "utf-8"); //keep-alive headermap.put("connection", "keep-alive"); headermap.put("content-type", "multipart/form-data; boundary=" + boundary); return headermap; } @override public byte[] getbody() throws authfailureerror { //传参数 stringbuilder sb = new stringbuilder(); for (map.entry<string, string> entry : mparams.entryset()) { // 构建表单字段内容 sb.append("--"); sb.append(boundary); sb.append("\r\n"); sb.append("content-disposition: form-data; name=\"" + entry.getkey() + "\"\r\n\r\n"); sb.append(entry.getvalue()); sb.append("\r\n"); } return sb.tostring().getbytes(); } @override public void handrequest(outputstream out) { dataoutputstream dos = (dataoutputstream) out; try { //发送文件数据 if (files != null) { for (formfile file : files) { // 发送文件数据 stringbuilder split = new stringbuilder(); split.append("--"); split.append(boundary); split.append("\r\n"); split.append("content-disposition: form-data;name=\"" + file.getparametername() + "\";filename=\"" + file.getfilname() + "\"\r\n"); split.append("content-type: " + file.getcontenttype() + "\r\n\r\n"); dos.write(split.tostring().getbytes()); if (file.getinstream() != null) { byte[] buffer = new byte[1024]; int len = -1; int count = 0; while ((len = file.getinstream().read(buffer)) != -1) { dos.write(buffer, 0, len); count += len; if (mlistener != null) { mlistener.onprogresschange(file.getfilesize(), count); } } count = 0; file.getinstream().close(); } else { dos.write(file.getdata(), 0, file.getdata().length); } dos.write("\r\n".getbytes()); } } dos.writebytes("--" + boundary + "--\r\n"); dos.flush(); } catch (ioexception e) { mlistener.onerror(new volleyerror(e.tostring())); try { dos.close(); } catch (ioexception e1) { e1.printstacktrace(); } } } @override protected response<string> parsenetworkresponse(networkresponse response) { string parsed; try { parsed = new string(response.data, httpheaderparser.parsecharset(response.headers)); } catch (unsupportedencodingexception e) { parsed = new string(response.data); } return response.success(parsed, httpheaderparser.parsecacheheaders(response)); } @override protected void deliverresponse(string response) { mlistener.onsuccess(response); } @override public void delivererror(volleyerror error) { mlistener.onerror(error); } }
附上demo连接:android实现文件上传功能
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