#1.下载utils项目

https://github.com/wyouflf/xUtils

#2布局文件里实现UI

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"xmlns:tools="http://schemas.android.com/tools"android:layout_width="match_parent"android:layout_height="match_parent"android:orientation="vertical"tools:context=".MainActivity" ><EditTextandroid:id="@+id/tv_path"android:layout_width="match_parent"android:layout_height="wrap_content"android:text="http://down.360safe.com/inst.exe" /><Buttonandroid:layout_marginTop="10dip"android:layout_width="match_parent"android:onClick="download"android:layout_height="wrap_content"android:text="下载"/><TextViewandroid:id="@+id/tv_info"android:layout_width="match_parent"android:layout_marginTop="10dip"android:layout_height="wrap_content"android:text="提示信息"/></LinearLayout>

#3.在mainactivity中实现代码功能

package com.wzw.downloaddemo;import java.io.File;import com.lidroid.xutils.HttpUtils;
import com.lidroid.xutils.exception.HttpException;
import com.lidroid.xutils.http.HttpHandler;
import com.lidroid.xutils.http.ResponseInfo;
import com.lidroid.xutils.http.callback.RequestCallBack;import android.os.Bundle;
import android.app.Activity;
import android.view.Menu;
import android.view.View;
import android.widget.EditText;
import android.widget.TextView;public class MainActivity extends Activity {private EditText etPath;private TextView tvInfo;@Overrideprotected void onCreate(Bundle savedInstanceState) {super.onCreate(savedInstanceState);setContentView(R.layout.activity_main);etPath=(EditText) findViewById(R.id.tv_path);tvInfo=(TextView) findViewById(R.id.tv_info);}public void download(View v){String path =etPath.getText().toString();HttpUtils http = new HttpUtils();http.download(path, "/sdcard/360.exe", true, true, new RequestCallBack<File>() {<span style="white-space:pre">    </span>@Overridepublic void onStart() {tvInfo.setText("正在连接...");}@Overridepublic void onLoading(long total, long current, boolean isUploading) {tvInfo.setText(current + "/" + total);}@Overridepublic void onFailure(HttpException error, String msg) {tvInfo.setText(msg);}@Overridepublic void onSuccess(ResponseInfo<File> responseInfo) {// TODO Auto-generated method stubtvInfo.setText("downloaded:" + responseInfo.result.getPath());}});}}

用Utils的话比用传统的方式要方便的多。