如何制作能查看网络图片的简单应用

以下是效果图：



activity_main.xml

<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"

android:paddingBottom="@dimen/activity_vertical_margin"

android:paddingLeft="@dimen/activity_horizontal_margin"

android:paddingRight="@dimen/activity_horizontal_margin"

android:paddingTop="@dimen/activity_vertical_margin"

tools:context=".MainActivity" >

<ImageView

android:id="@+id/ivImage"

android:layout_width="288dp"

android:layout_height="wrap_content"

android:layout_gravity="center"

android:layout_weight="0.82"

android:src="@drawable/ic_launcher" />

<EditText

android:id="@+id/etImageUrl"

android:layout_width="match_parent"

android:layout_height="wrap_content"

android:ems="10"

android:text="http://img4q.duitang.com/uploads/item/201303/17/20130317141530_kWFkv.jpeg"

android:hint="请输入图片的地址" />

<Button

android:id="@+id/btnView"

android:layout_width="100dp"

android:layout_height="48dp"

android:layout_gravity="center"

android:background="@drawable/button_bg"

android:onClick="showImage"

android:text="浏览" />

</LinearLayout>

MainActivity.java

package com.example.showimageview;

import java.io.IOException;

import java.io.InputStream;

import java.net.HttpURLConnection;

import java.net.MalformedURLException;

import java.net.URL;

import java.util.logging.Handler;

import java.util.logging.LogRecord;

import org.xml.sax.HandlerBase;

import android.app.Activity;

import android.graphics.Bitmap;

import android.graphics.BitmapFactory;

import android.os.Bundle;

import android.os.HandlerThread;

import android.os.Message;

import android.text.TextUtils;

import android.view.Menu;

import android.view.View;

import android.widget.Button;

import android.widget.EditText;

import android.widget.ImageView;

import android.widget.Toast;

public class MainActivity extends Activity {

private ImageView ivImage;

private EditText etImageUrl;

private Button btnView;

public static final int SHOWIMAGE=1;

private android.os.Handler handler=new android.os.Handler(){

public void handleMessage(Message msg){

switch (msg.what) {

case SHOWIMAGE:

Bitmap bitmap=(Bitmap) msg.obj;

ivImage.setImageBitmap(bitmap);

break;

default:

break;

}

};

};

protected void onCreate(Bundle savedInstanceState) {

super.onCreate(savedInstanceState);

setContentView(R.layout.activity_main);

initViews();

}

private void initViews() {

btnView=(Button) findViewById(R.id.btnView);

etImageUrl=(EditText) findViewById(R.id.etImageUrl);

ivImage= (ImageView) findViewById(R.id.ivImage);

}

@Override

public boolean onCreateOptionsMenu(Menu menu) {

getMenuInflater().inflate(R.menu.main, menu);

return true;

}

public void showImage(View view){

final String path=etImageUrl.getText().toString();

if(TextUtils .isEmpty(path)){

Toast.makeText(this, "图片路径不为空", Toast.LENGTH_LONG).show();

}else{

new Thread(){

public void run(){

try {

URL url=new URL(path);

HttpURLConnection connection=(HttpURLConnection) url.openConnection();

connection.setRequestMethod("GET");

connection.setConnectTimeout(5000);

int responseCode=connection.getResponseCode();

if(responseCode==200){

InputStream inputStream=connection.getInputStream();

Bitmap bitmap=BitmapFactory.decodeStream(inputStream);

//ivImage.setImageBitmap(bitmap);

Message message=new Message();

message.what=SHOWIMAGE;

message.obj=bitmap;

handler.sendMessage(message);

}

} catch (MalformedURLException e) {

e.printStackTrace();

} catch (IOException e) {

e.printStackTrace();

}

};

}.start();

}

}

}

AndroidMainifest.xml

<?xml version="1.0" encoding="utf-8"?>

<manifest xmlns:android="http://schemas.android.com/apk/res/android"

package="com.example.showimageview"

android:versionCode="1"

android:versionName="1.0" >

<uses-sdk

android:minSdkVersion="14"

android:targetSdkVersion="17" />

<uses-permission android:name="android.permission.INTERNET" />

<application

android:allowBackup="true"

android:icon="@drawable/ic_launcher"

android:label="@string/app_name"

android:theme="@style/AppTheme" >

<activity

android:name="com.example.showimageview.MainActivity"

android:label="@string/app_name" >

<intent-filter>

<action android:name="android.intent.action.MAIN" />

<category android:name="android.intent.category.LAUNCHER" />

</intent-filter>

</activity>

</application>

</manifest>