android如何创建自己的监听接口.doc

android如何创建自己的监听接口 第一步：创建接口和方法 public interface OnUsernameAvailableListener { public abstract void onAvailableChecked(String username, boolean available); } 第二步：定义变量保存listener OnUsernameAvailableListener onUsernameAvailableListener = null; 第三步：提供方法允许用户设置Listener // Allows the user to set an Listener and react to the event public void setOnUsernameAvailableListener(OnUsernameAvailableListener listener) { onUsernameAvailableListener = listener; } 第四步：提供方法允许用户获得Listener public final OnUsernameAvailableListener getOnUsernameAvailableListener() { return onUsernameAvailableListener; } 第五步：添加方法，此方法每次在监听事件被触发的时候调用 // This function is called after the check was complete private void OnUserChecked(String username, boolean available){ // Check if the Listener was set, otherwise well get an Exception when we try to call it if(onUsernameAvailableListener!=null) { // Only trigger the event, when we have a username if(!TextUtils.isEmpty(username)){ onUsernameAvailableListener.onAvailableChecked(username, available); } } } 完成。 附完整代码： package com.tseng.examples; import com.tseng.examples.CheckUsernameEditText.OnUsernameAvailableListener; import android.app.Activity; import android.graphics.Color; import android.os.Bundle; import android.view.View; import android.view.View.OnClickListener; import android.widget.Button; import android.widget.EditText; import android.widget.TextView; public class RegisterExample extends Activity { // Declare our Views, so we can access them later private CheckUsernameEditText etUsername; private EditText etPassword; private EditText etPassword2; private Button btnRegister; private Button btnCancel; private TextView lblUserStatus; /** Called when the activity is first created. */ @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); // Set Activity Layout setContentView(R.layout.main); // Get the EditText and Button References etUsername =