Android 网络图片查看器

StreamTool：将InputStream转化为ByteArray

package util;

import java.io.ByteArrayOutputStream;
import java.io.InputStream;

public class StreamTool {
/**
* 把一个inputstream里面的内容转化成一个byte[]
*/

public static byte[] getBytes(InputStream is) throws Exception {
ByteArrayOutputStream bos = new ByteArrayOutputStream();
byte[] buffer = new byte[1024];
int len = 0;
while ((len = is.read(buffer)) != -1) {
bos.write(buffer, 0, len);
}
is.close();
bos.flush();
byte[] result = bos.toByteArray();
System.out.println(new String(result));
return result;
}
}NetUtil.java:
package service;

import java.io.InputStream;
import java.net.HttpURLConnection;
import java.net.MalformedURLException;
import java.net.URL;
import java.net.URLConnection;

import util.StreamTool;

import android.graphics.Bitmap;
import android.graphics.BitmapFactory;

public class NetUtil {
/**
* 获取网络address地址对应的图片
*
* @param address
* @return bitmap的类型
*/
public static Bitmap getImage(String address) throws Exception {
// 通过代码 模拟器浏览器访问图片的流程
URL url = new URL(address);
HttpURLConnection conn = (HttpURLConnection) url.openConnection();
conn.setRequestMethod("GET");
conn.setConnectTimeout(5000);
// 获取服务器返回回来的流
InputStream is = conn.getInputStream();
byte[] imagebytes = StreamTool.getBytes(is);
Bitmap bitmap = BitmapFactory.decodeByteArray(imagebytes, 0,
imagebytes.length);
return bitmap;
}
}MainActivity

package com.example.entimageviewer;

import java.io.IOException;
import java.net.SocketTimeoutException;

import service.NetUtil;

import android.app.Activity;
import android.graphics.Bitmap;
import android.os.Bundle;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.EditText;
import android.widget.ImageView;
import android.widget.Toast;

public class MainActivity extends Activity implements OnClickListener {
private EditText mEtAddress;
private Button mBtView;
private ImageView mIvView;

@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
mEtAddress = (EditText) this.findViewById(R.id.editText1);
mBtView = (Button) this.findViewById(R.id.chakan);
mIvView = (ImageView) this.findViewById(R.id.imageView1);
mBtView.setOnClickListener(this);
}

public void onClick(View v) {
switch (v.getId()) {
case R.id.chakan:
// 按钮对应的点击事件
String address = mEtAddress.getText().toString().trim();
if ("".equals(address)) {
Toast.makeText(this, "图片地址不能为空", Toast.LENGTH_SHORT).show();
return;
}
try {
Bitmap bitmap = NetUtil.getImage(address);
mIvView.setImageBitmap(bitmap);
} catch (Exception e) {
if (e instanceof SocketTimeoutException) {
Toast.makeText(this, "网络连接超时", Toast.LENGTH_SHORT).show();
} else if (e instanceof IOException) {
Toast.makeText(this, "读取数据错误 ", Toast.LENGTH_SHORT).show();
} else {
Toast.makeText(this, "未知错误 ", Toast.LENGTH_SHORT).show();
}
e.printStackTrace();
}
break;
}
}
}

main.xml:
<?xml version="1.0" encoding="utf-8"?><LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical" >

<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="@string/input_address" />

<EditText
android:id="@+id/editText1"
android:layout_width="match_parent"
android:lines="2"
android:text="http://172.16.40.157:8080/tomcat.png"
android:layout_height="wrap_content" />

<Button
android:id="@+id/chakan"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:text="@string/go" />
<ImageView
android:id="@+id/imageView1"
android:scaleType="center"
android:layout_width="match_parent"
android:layout_height="match_parent" />

</LinearLayout>