Android - This Handler class should be static or leaks might occur.

package spt.http.get.activity;


import java.lang.ref.WeakReference;

import spt.http.get.assist.SendDataToServer;
import android.app.Activity;
import android.os.Bundle;
import android.os.Handler;
import android.os.Message;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.Toast;

public class MainActivity extends Activity {
	//view.
	private EditText edt_name = null;
	private EditText edt_pwd = null;
	private Button btn_ok = null;

	@Override
	protected void onCreate(Bundle savedInstanceState) {
		super.onCreate(savedInstanceState);
		setContentView(R.layout.activity_main);
		initView();
		initListener();
	}
	
	/**
	 * 初始化View.
	 */
	private void initView() {
		edt_name = (EditText)findViewById(R.id.edt_name);
		edt_pwd = (EditText)findViewById(R.id.edt_pwd);
		btn_ok = (Button)findViewById(R.id.btn_ok);
		
		//test:
		edt_name.setText("你好");
		edt_pwd.setText("abc");
	}
	
	/**使用静态内部类,解决‘This Handler class should be static or leaks might occur‘,以免造成内存泄露.
	 * @author Administrator
	 *
	 */
	private static class StatusHandler extends Handler {
		WeakReference<MainActivity>  iMainActivity = null;
		
		public StatusHandler(MainActivity mainActivity) {
			iMainActivity = new WeakReference<MainActivity>(mainActivity);
		}
		
		@Override
		public void handleMessage(Message msg) {
			switch (msg.what) {
			case SendDataToServer.SEND_SUCCESS:
				//有iMainActivity.get()和iMainActivity.getClass().
				Toast.makeText(iMainActivity.get(), "发送成功", Toast.LENGTH_SHORT).show();
				break;
			case SendDataToServer.SEND_FAIL:
				Toast.makeText(iMainActivity.get(), "发送失败", Toast.LENGTH_SHORT).show();
				break;
			default:
				throw new RuntimeException("未知的发送结果!");
			}
		}
	}

	/**
	 * 处理发送是否成功的状态的Handler.
	 */
	private final  Handler handler = new StatusHandler(this);
	
	/**
	 * 初始化监听器.
	 */
	private void initListener() {
		btn_ok.setOnClickListener(new Button.OnClickListener() {
			
			@Override
			public void onClick(View v) {
				String name = edt_name.getText().toString();
				String pwd = edt_pwd.getText().toString();
				if(name.isEmpty() || pwd.isEmpty()) {
					Toast.makeText(MainActivity.this, "用户名和密码不能为空", Toast.LENGTH_SHORT).show();
					return;
				}
				new SendDataToServer(handler).send(name, pwd);
			}
		});
	}
}