Android实现网络图片查看器

                         Android实现从互联网上获取图片

       效果图如下：



   xml: <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" />

<Button
android:id="@+id/btnView"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="center"
android:background="@drawable/button_bg"
android:onClick="viewImage"
android:text="浏览" />

      java代码：
public class MainActivity extends Activity {
private EditText etImageUrl;
private ImageView ivImage;
public static final int SHOWIMAGE=1;
private Handler handler=new Handler(){
public void handleMessage(android.os.Message msg) {
switch (msg.what) {
case SHOWIMAGE:
Bitmap bitmap=(Bitmap) msg.obj;
ivImage.setImageBitmap(bitmap);
break;

default:
break;
}
};
};
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
initViews();
}

private void initViews() {
etImageUrl=(EditText) findViewById(R.id.etImageUrl);
ivImage=(ImageView) findViewById(R.id.ivImage);
}

@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 viewImage(View view){
final String imageUrl=etImageUrl.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{
Toast.makeText(MainActivity.this, "显示图片失败", Toast.LENGTH_LONG).show();
}
} catch (MalformedURLException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}

}
}.start();

}
}

}