安卓使用URL显示网络图片

暑假第三篇 

设计思路：

import java.io.File;  
import java.io.FileOutputStream;  
import java.io.InputStream;  
import android.content.Context;  
<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="match_parent"  
        android:layout_height="wrap_content"  
        android:layout_gravity="center"  
        android:layout_weight="1" />  
  
    <EditText  
        android:id="@+id/etImageUrl"  
        android:layout_width="match_parent"  
        android:layout_height="wrap_content"  
        android:ems="10"  
        android:hint="请输入图片的地址"  
        android:text="http://epaper.yangtse.com/images/2010-06/24/A39/YZA39624C005_b.jpg" />  
  
    <Button  
        android:id="@+id/btnView"  
        android:layout_width="wrap_content"  
        android:layout_height="wrap_content"  
        android:layout_gravity="center"  
        android:onClick="viewImage"  
        android:text="浏览" />  
  
</LinearLayout>  

package com.example.xianshitupian;

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

import android.os.Bundle;
import android.os.Handler;
import android.os.Message;
import android.app.Activity;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
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 xstp;
private EditText xdz;
private Button liulan;
public static final int SHOWIMAGE=1;
public static final int SHOWFAIL=0;
private Handler handler=new Handler(){
public void handleMessage(android.os.Message msg) {
switch (msg.what) {
case SHOWIMAGE:
Bitmap bitmap=(Bitmap) msg.obj;
xstp.setImageBitmap(bitmap);
break;

case SHOWFAIL:
xstp.setImageResource(R.drawable.button_bg);
Toast.makeText(MainActivity.this, "显示图片失败", Toast.LENGTH_LONG).show();
break;

default:
break;
}
};
};

@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
xstp=(ImageView) findViewById(R.id.ivImage);
xdz=(EditText) findViewById(R.id.etdizhi);
xstp.setImageResource(R.drawable.button_bg);
}

@Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.main, menu);
return true;
}
public void star(View view){
final String imageUrl=xdz.getText().toString();
if(TextUtils.isEmpty(imageUrl)){
Toast.makeText(this, "图片路径不能为空", Toast.LENGTH_LONG).show();
}else{
new Thread(){
public void run() {
try {
URL url=new URL(imageUrl);
HttpURLConnection httpURLConnection=(HttpURLConnection) url.openConnection();
httpURLConnection.setRequestMethod("GET");
httpURLConnection.setConnectTimeout(5000);
int responseCode=httpURLConnection.getResponseCode();
if(responseCode==200){
InputStream inputStream=httpURLConnection.getInputStream();
Bitmap bitmap=BitmapFactory.decodeStream(inputStream);
Message message=new Message();
message.what=SHOWIMAGE;
message.obj=bitmap;
//ivImage.setImageBitmap(bitmap);
handler.sendMessage(message);
}else{
Message message=new Message();
message.what=SHOWFAIL;
handler.sendMessage(message);
}
} catch (MalformedURLException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
}
}.start();
}
}
}