<?xml version="1.0" encoding="utf-8"?><!--  Copyright 2012 GitHub Inc.  Licensed under the Apache License, Version 2.0 (the "License");  you may not use this file except in compliance with the License.  You may obtain a copy of the License at  http://www.apache.org/licenses/LICENSE-2.0  Unless required by applicable law or agreed to in writing, software  distributed under the License is distributed on an "AS IS" BASIS,  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.  See the License for the specific language governing permissions and  limitations under the License.--><rotate xmlns:android="http://schemas.android.com/apk/res/android"  android:duration="2000"  android:fromDegrees="0"  android:interpolator="@android:anim/linear_interpolator"  android:pivotX="50%"  android:pivotY="50%"  android:toDegrees="360" />

package com.example.actionbarmenubtnrefresh;import android.os.Bundle;import android.app.Activity;import android.view.Menu;import android.view.MenuItem;import android.view.View;import android.view.animation.Animation;import android.view.animation.AnimationUtils;import android.widget.ImageView;import android.widget.Toast;public class MainActivity extends Activity {    protected MenuItem refreshItem;        private boolean isRefreshState = false;            @Override    protected void onCreate(Bundle savedInstanceState) {        super.onCreate(savedInstanceState);        setContentView(R.layout.main);    }    @Override    public boolean onCreateOptionsMenu(Menu menu) {        //MenuInflater实例化Menu目录下的Menu布局文件        getMenuInflater().inflate(R.menu.main, menu);        return true;    }    @Override    public boolean onOptionsItemSelected(MenuItem item) {        switch (item.getItemId()) {        case R.id.action_refresh:            refreshMenuItemView(item);            Toast.makeText(getBaseContext(), "开始刷新", Toast.LENGTH_SHORT).show();            break;        case R.id.action_stop:            hideRefreshAnimation();            Toast.makeText(getBaseContext(), "停止刷新", Toast.LENGTH_SHORT).show();            break;        default:            break;        }        return super.onOptionsItemSelected(item);    }    private void refreshMenuItemView(MenuItem item) {        hideRefreshAnimation();        refreshItem = item;                //LayoutInflater实例化整个布局文件        //使用ImageView设置成MenuItem的ActionView        ImageView refreshView = (ImageView)getLayoutInflater().inflate(R.layout.refresh_view, null);        refreshView.setImageResource(R.drawable.ic_action_refresh);        refreshItem.setActionView(refreshView);        //显示刷新动画        Animation animation = AnimationUtils.loadAnimation(this, R.anim.refresh);        //设置重复模式  Defines what this animation should do when it reaches the end        animation.setRepeatMode(Animation.RESTART);        //设置重复次数        animation.setRepeatCount(Animation.INFINITE);        //使用ImageView 显示旋转动画        refreshView.startAnimation(animation);        isRefreshState = true;    }        private void hideRefreshAnimation() {        if (refreshItem != null) {            View view = refreshItem.getActionView();            if (view != null) {                view.clearAnimation();                refreshItem.setActionView(null);                isRefreshState = false;            }        }    }    }