首先,开始最简单的网络编程实战,URL实现网络连接,不懂的童鞋可以参考JAVA中的URL编程,其原理是一样的,在这里不再多做解释。
直接贴出实现源代码:
public class DataActivity extends Activity {
private EditText imagePathText;
private static final String TAG="DataActivity";
private ImageView imageView;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
imagePathText = (EditText) findViewById(R.id.imagepath);
imageView=(ImageView)findViewById(R.id.imageView);
Button button = (Button) findViewById(R.id.button);
button.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
String path = imagePathText.getText().toString();
try {
byte[] data=NetTool.getImage(path);
Bitmap bm=BitmapFactory.decodeByteArray(data, 0, data.length);
imageView.setImageBitmap(bm);
} catch (Exception e) {
Log.i(TAG, e.toString());
Toast.makeText(DataActivity.this, "获得图片失败", 1).show();
}
}
});
// 获取网页源代码
Button sinaButton = (Button) findViewById(R.id.sinaButton);
sinaButton.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
Intent intent=new Intent(DataActivity.this,SinaActivity.class);
startActivity(intent);
}
});
}
}
public class SinaActivity extends Activity {
private TextView textView;
private static final String TAG="SinaActivity";
// 获取网页源代码
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.sina);
textView=(TextView)this.findViewById(R.id.sina);
try {
String html=NetTool.getHtml("http://www.sina.com.cn","GBK");
textView.setText(html);
} catch (Exception e) {
Log.i(TAG, e.toString());
Toast.makeText(SinaActivity.this, "获得网页失败", 1).show();
}
}
}
public class NetTool {
/**
* 获得url代码数据
* */
public static String getHtml(String path,String encoding) throws Exception {
URL url = new URL(path);
HttpURLConnection conn = (HttpURLConnection) url.openConnection();
conn.setRequestMethod("GET");
conn.setConnectTimeout(6 * 1000);
// 别超过6秒。
System.out.println(conn.getResponseCode());
if(conn.getResponseCode()==200){
InputStream inputStream=conn.getInputStream();
byte[] data=readStream(inputStream);
return new String(data,encoding);
}
return null;
}
/**
* 获取指定路径,的数据。
*
* **/
public static byte[] getImage(String urlpath) throws Exception {
URL url = new URL(urlpath);
HttpURLConnection conn = (HttpURLConnection) url.openConnection();
conn.setRequestMethod("GET");
conn.setConnectTimeout(6 * 1000);
// 别超过6秒。
if(conn.getResponseCode()==200){
InputStream inputStream=conn.getInputStream();
return readStream(inputStream);
}
return null;
}
/**
* 读取数据
* 输入流
*
* */
public static byte[] readStream(InputStream inStream) throws Exception {
ByteArrayOutputStream outstream=new ByteArrayOutputStream();
byte[] buffer=new byte[1024];
int len=-1;
while((len=inStream.read(buffer)) !=-1){
outstream.write(buffer, 0, len);
}
outstream.close();
inStream.close();
return outstream.toByteArray();
}
}