ListView动态加载数据模板(使用代码布局)

1、对于做Android应用程序来说，ListView一定用得非常多，经常解析xml文件然后在ListView中显示，往往我们需要让它动态地加载内容，也就是不一次性地加载完成，对于手机来说，这点很重要！笔者之前也是弄的不明白，用的时候直接在网上找代码，复制粘贴，再修改一下就是自己的了，笔者的这个小Demo灵感来自于新浪或者腾讯微博手机客户端，比如第一页加载十条Item，当翻到最后一个Item的时候，会出来一个Button，当点击Button的时候就会继续加载更多的，当然如果不点，就不会加载的，节约用户流量，先看效果图OK，如果觉得满意的话就继续看下面的代码吧，笔者这里没有用到main.xml文件，

2、全部在java文件中定义的，如果理解了的话自己可以在xml文件里面写布局package com.focus.loading;import android.app.ListActivity;import android.os.Bundle;import android.os.Handler;import android.view.Gravity;import android.view.View;import android.view.View.OnClickListener;import android.view.ViewGroup;import android.view.ViewGroup.L

3、ayoutParams;import android.widget.AbsListView;import android.widget.AbsListView.OnScrollListener;import android.widget.BaseAdapter;import android.widget.Button;import android.widget.LinearLayout;import android.widget.ListView;import android.widget.ProgressBar;import android.widget.TextView;public cl

4、ass ListViewActivity extends ListActivity implements OnScrollListener private LinearLayout mLoadLayout;private LinearLayout mProgressLoadLayout;private ListView mListView;private ListViewAdapter mListViewAdapter = new ListViewAdapter(;private int mLastItem = 0;private int mCount = 41;private final H

5、andler mHandler = new Handler(;/ 在Handler中加载数据private final LayoutParams mLayoutParams = new LinearLayout.LayoutParams(LinearLayout.LayoutParams.WRAP_CONTENT,LinearLayout.LayoutParams.WRAP_CONTENT;int scrollState;/ 全局变量，用来记录ScrollView的滚动状态，1表示开始滚动，2表示正在滚动，0表示滚动停止int visibleItemCount;/ 当前可见页面中的Item总数

6、Overridepublic void onCreate(Bundle savedInstanceState super.onCreate(savedInstanceState;/* "加载项"布局，此布局被添加到ListView的Footer中。*/mLoadLayout = new LinearLayout(this;mLoadLayout.setMinimumHeight(30;mLoadLayout.setGravity(Gravity.CENTER;mLoadLayout.setOrientation(LinearLayout.VERTICAL;/* 当点击按钮的

7、时候显示这个View，此View使用水平方式布局，左边是一个进度条，右边是文本，默认设为不可见*/mProgressLoadLayout = new LinearLayout(this;mProgressLoadLayout.setMinimumHeight(30;mProgressLoadLayout.setGravity(Gravity.CENTER;mProgressLoadLayout.setOrientation(LinearLayout.HORIZONTAL;ProgressBar mProgressBar = new ProgressBar(this;mProgressBar.s

8、etPadding(0, 0, 15, 0;mProgressLoadLayout.addView(mProgressBar, mLayoutParams;/ 为布局添加进度条TextView mTipContent = new TextView(this;mTipContent.setText("加载中."mProgressLoadLayout.addView(mTipContent, mLayoutParams;/ 为布局添加文本mProgressLoadLayout.setVisibility(View.GONE;/ 默认设为不可见，注意View.GONE和View.

9、INVISIBLE的区别mLoadLayout.addView(mProgressLoadLayout;/ 把之前的布局以View对象添加进来final Button button = new Button(this;button.setText("加载更多"/ 添加按钮mLoadLayout.addView(button, new LayoutParams(LayoutParams.FILL_PARENT,LayoutParams.WRAP_CONTENT;button.setOnClickListener(new OnClickListener( Overridepub

10、lic void onClick(View v if (mLastItem = mListViewAdapter.count&& scrollState = OnScrollListener.SCROLL_STATE_IDLE / 当点击时把带进度条的Layout设为可见，把Button设为不可见mProgressLoadLayout.setVisibility(View.VISIBLE;button.setVisibility(View.GONE;if (mListViewAdapter.count <= mCount mHandler.postDelayed(new

11、Runnable( Overridepublic void run( mListViewAdapter.count += 10;mListViewAdapter.notifyDataSetChanged(;mListView.setSelection(mLastItem- visibleItemCount + 1;/ 获取数据成功时把Layout设为不可见，把Button设为可见mProgressLoadLayout.setVisibility(View.GONE;button.setVisibility(View.VISIBLE;, 2000;mListView = getListView(

12、;mListView.addFooterView(mLoadLayout;setListAdapter(mListViewAdapter;mListView.setOnScrollListener(this;Overridepublic void onScroll(AbsListView view, int firstVisibleItem,int visibleItemCount, int totalItemCount this.visibleItemCount = visibleItemCount;mLastItem = firstVisibleItem + visibleItemCoun

13、t - 1;if (mListViewAdapter.count > mCount mListView.removeFooterView(mLoadLayout;Overridepublic void onScrollStateChanged(AbsListView view, int scrollState this.scrollState = scrollState;class ListViewAdapter extends BaseAdapter int count = 10;public int getCount( return count;public Object getItem(int position return position;public long getItemId(int position return position;public View getView(int position, View view, ViewGroup parent TextView mTextView;if (view = null mTextView = new TextView(ListViewActivity.this; e