界面中有三个控件，一个EditText，一个Button，一个ImageView
1、下面是具体布局文件
<EditText
android:id="@+id/picturepagh"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:text="@string/hello_world"
/>
<Button
android:id="@+id/btn"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:text="查看"
/>
<ImageButton
android:id="@+id/imageView"
android:layout_width="fill_parent"
android:layout_height="200px"
/>
2、在MainActivity中进行图片图示代码编写
public class MainActivity extends Activity {
private Button
btn;
private EditText path;
private ImageView imgview;
@Override
protected void onCreate(Bundle savedInstanceState)
{
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
btn
= (Button) findViewById(R.id.btn);
path = (EditText)
findViewById(R.id.picturepagh);
imgview = (ImageView)
findViewById(R.id.imageView);
btn.setOnClickListener(new OnClickListener() {
@Override
public
void onClick(View v) {
Log.i("CLICK", ((Button)
v).getText().toString());
new
Thread(runa).start();
}
});
}
public void setView() {
String picturepath =
path.getText().toString();
byte[] data = null;
try {
data =
ImageService.getImage(picturepath);
Bitmap bitmap =
BitmapFactory.decodeByteArray(data, 0, data.length);//
BitmapFactory：图片工厂！
Looper.prepare();// 必须调用此方法，要不然会报错
Message msg =
new Message();
msg.what = 0;
msg.obj =
bitmap;
handler.sendMessage(msg);
} catch (Exception e)
{
Toast.makeText(getApplicationContext(), "获取图片错误",
1).show();
}
}
private Handler handler = new Handler() {
@Override
public void
handleMessage(Message msg) {
if (msg.what == 0)
{
updateImageView((Bitmap) msg.obj);
}
}
};
private Runnable runa = new Runnable() {
@Override
public void
run() {
setView();
}
};
private void updateImageView(Bitmap bm)
{
imgview.setImageBitmap(bm);
}
}
3、添加一个ImageService图片服务类，里面包含一个获取网络数据的方法；
public class ImageService {
// 获取网络图片的数据
public static byte[] getImage(String picturepath) throws
Exception {
URL url = new URL(picturepath);
HttpURLConnection conn =
(HttpURLConnection) url.openConnection();//
基于http协议的连接对象
conn.setConnectTimeout(10);//
10秒；
conn.setRequestMethod("GET");// 大写
if (conn.getResponseCode() ==
200) {
InputStream ins = conn.getInputStream();
return
StreamTool.read(ins);
}
return null;
}
}
4、添加一个流处理工作类StreamTool
public class StreamTool {
public static byte[] read(InputStream ins) throws Exception
{
ByteArrayOutputStream outstream = new
ByteArrayOutputStream();
byte[] buffer = new byte[1024];
int length =
0;
while ((length = ins.read(buffer)) > -1)
{
outstream.write(buffer, 0,
length);
}
outstream.close();
return
outstream.toByteArray();
}
}
5、大功告成？NO，还要添加网络访问权限： <uses-permission
android:name="android.permission.INTERNET" />
OK，运行程序！