使用http協議獲取網路圖片
http用於傳輸WWW方式的資料。http協議採用了請求響應的模型。在android中提供了HttpURLConnection和HttpClient介面開發HTTP程式。下面分別使用這兩種方式獲取網路圖片。
1.HttpURLConnection
程式碼如下：
public class HttpURLConnectionActivity extends Activity {
private ImageView imageView;
@Override
protected void onCreate(Bundle savedInstanceState) {
// TODO Auto-generated method stub
super.onCreate(savedInstanceState);
setContentView(R.layout.simple1);
imageView=(ImageView) this.findViewById(R.id.imageView1);
//傳入網路圖片地址
try {
URL url = new URL("http://news.xinhuanet.com/photo/2012-02/09/122675973_51n.jpg");
HttpURLConnection conn= (HttpURLConnection) url.openConnection();
conn.setRequestMethod("GET");
conn.setConnectTimeout(5*1000);
conn.connect();
InputStream in=conn.getInputStream();
ByteArrayOutputStream bos=new ByteArrayOutputStream();
byte[] buffer=new byte[1024];
int len = 0;
while((len=in.read(buffer))!=-1){
bos.write(buffer,0,len);
}
byte[] dataImage=bos.toByteArray();
bos.close();
in.close();
Bitmap bitmap=BitmapFactory.decodeByteArray(dataImage, 0, dataImage.length);
//Drawable drawable=BitmapDrawable.
imageView.setImageBitmap(bitmap);
} catch (Exception e) {
// TODO Auto-generated catch block
e.printStackTrace();
Toast.makeText(getApplicationContext(), "圖片載入失敗", 1).show();
}
}
}
最後不要忘記在manifest.xml加入網路訪問許可權：
<uses-permission android:name="android.permission.INTERNET" /> 由於訪問網路圖片是比較耗時的操作，所以在正式專案中使用非同步載入圖片，效果會更好。
執行效果：
2.HttpClient
下面使用HttpClient獲取網頁內容：
public class HttpClientActivity extends Activity {
private ImageView imageview;
private TextView text;
@Override
protected void onCreate(Bundle savedInstanceState) {
// TODO Auto-generated method stub
super.onCreate(savedInstanceState);
setContentView(R.layout.simple2);
imageview=(ImageView) this.findViewById(R.id.imageView2);
text=(TextView) this.findViewById(R.id.textView2);
HttpGet httpGet=new HttpGet("http://cloud.csdn.net/a/20120209/311628.html");
HttpClient httpClient=new DefaultHttpClient();
try {
//得到HttpResponse物件
HttpResponse httpResponse=httpClient.execute(httpGet);
//HttpResponse的返回結果是不是成功
if(httpResponse.getStatusLine().getStatusCode()==HttpStatus.SC_OK){
//得到返回資料的字串
String dataImageStr=EntityUtils.toString(httpResponse.getEntity());
text.setText(dataImageStr);
}
} catch (ClientProtocolException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
}
執行效果：
這樣就成功載入了網頁內容。