[Android進階]使用HttpURLConnection實現網頁源碼的下載

上一篇文章主要介紹的圖片文件的下載與顯示，這一篇文章主要介紹如何根據網頁的地址，獲取網頁源代碼的獲取

其實，網站源代碼的獲取比圖片的下載與顯示更加簡單，只需要對之前的代碼稍作修改即可

public class OtherActivity extends Activity {

	private TextView tv;
	private static final int LOAD_SUCCESS = 1;
	private static final int LOAD_ERROR = -1;
	private Handler handler = new Handler() {
		public void handleMessage(Message msg) {

			switch (msg.what) {
			case LOAD_SUCCESS:
				tv.setText((String) msg.obj);
				break;
			case LOAD_ERROR:
				Toast.makeText(getApplicationContext(), "加載失敗", 0).show();
				break;
			}

		};
	};

	@Override
	protected void onCreate(Bundle savedInstanceState) {
		super.onCreate(savedInstanceState);
		setContentView(R.layout.activity_main);
		tv = (TextView) findViewById(R.id.tv);
	}

	// Button的點擊事件
	public void show(View view) {
		new Thread(new Runnable() {
			public void run() {
				getHttp();
			}
		}).start();

	}

	// 下載圖片的主方法
	private void getHttp() {
		URL url = null;
		InputStream is = null;
		ByteArrayOutputStream byteArrayOutputStream = null;
		try {
			// 構建圖片的url地址
			url = new URL("http://www.baidu.com");
			// 開啟連接
			HttpURLConnection conn = (HttpURLConnection) url.openConnection();
			// 設置超時的時間，5000毫秒即5秒
			conn.setConnectTimeout(5000);
			// 設置獲取圖片的方式為GET
			conn.setRequestMethod("GET");
			if (conn.getResponseCode() == 200) {
				is = conn.getInputStream();
				byteArrayOutputStream = new ByteArrayOutputStream();
				int len = 0;
				byte[] buffer = new byte[1024];
				while ((len = is.read(buffer)) != -1) {
					byteArrayOutputStream.write(buffer, 0, len);
				}
				byteArrayOutputStream.flush();
				byte[] arr = byteArrayOutputStream.toByteArray();
				Message msg = handler.obtainMessage();
				msg.what = LOAD_SUCCESS;
				msg.obj = new String(arr);
				handler.sendMessage(msg);
			}
		} catch (Exception e) {
			handler.sendEmptyMessage(LOAD_ERROR);
			e.printStackTrace();
		} finally {

			try {
				if (is != null) {
					is.close();
				}
				if (byteArrayOutputStream != null) {
					byteArrayOutputStream.close();
				}
			} catch (Exception e) {
				handler.sendEmptyMessage(LOAD_ERROR);
				e.printStackTrace();
			}
		}
	}

}