ListView 分段加载数据

ListView listView = getListView();
//添加到脚页显示  这个要继承ListActivity 实现OnScrollListener
listView.addFooterView(loadingLayout);

这位兄弟的Demo非常不错.

public class ListViewUpdate extends Activity implements OnScrollListener,
		OnItemClickListener {

	private List<ApplicationItemInfo> applicationItemInfoList;

	private List<ApplicationItemInfo> applicationItemInfoListTemp;

	private ApplicationItemAdapter applicationItemAdapter;

	private ListView listView;

	private LinearLayout loading;

	private Handler handler;

	private boolean refreshable;

	/** Called when the activity is first created. */
	@Override
	public void onCreate(Bundle savedInstanceState) {
		super.onCreate(savedInstanceState);
		init();
		updateApplicationItemInfoList();
	}

	private void init() {
		setContentView(R.layout.main);
		listView = (ListView) findViewById(R.id.list);
		loading = (LinearLayout) findViewById(R.id.loading);

		applicationItemInfoList = new ArrayList<ApplicationItemInfo>();
		applicationItemAdapter = new ApplicationItemAdapter(this,
				applicationItemInfoList);
		handler = createHandler();
		refreshable = true;

		listView.setAdapter(applicationItemAdapter);
		listView.setOnItemClickListener(this);
		listView.setOnScrollListener(this);
	}

	private Handler createHandler() {
		Handler handler = new Handler() {

			@Override
			public void handleMessage(Message msg) {
				// TODO Auto-generated method stub
				super.handleMessage(msg);
				switch (msg.what) {
				case 1:
					if (applicationItemInfoListTemp != null) {
						ListViewUpdate.this.applicationItemInfoList
								.addAll(applicationItemInfoListTemp);
						ListViewUpdate.this.applicationItemAdapter
								.notifyDataSetChanged();
						ListViewUpdate.this.loading
								.setVisibility(View.GONE);
						ListViewUpdate.this.refreshable = true;
					} else {
						ListViewUpdate.this.loading
								.setVisibility(View.GONE);
						Toast.makeText(ListViewUpdate.this,
								"All of applications have been shown!",
								Toast.LENGTH_LONG).show();
					}
					break;
				default:
					break;
				}
			}
		};
		return handler;
	}

	public Handler getHandler() {
		return handler;
	}

	private void updateApplicationItemInfoList() {
		new Thread(new Runnable() {

			@Override
			public void run() {
				// TODO Auto-generated method stub

				if (ListViewUpdate.this.applicationItemInfoList.size() < 80) {
					ListViewUpdate.this.applicationItemInfoListTemp = ListViewUpdate.this
							.getLocalApplicationInfo();
				} else {
					ListViewUpdate.this.applicationItemInfoListTemp = null;
				}

				try {
					Thread.sleep(5000);
				} catch (InterruptedException e) {
					// TODO Auto-generated catch block
					e.printStackTrace();
				}

				Message message = new Message();
				message.what = 1;
				ListViewUpdate.this.getHandler().sendMessage(message);
			}

		}).start();
	}

	private ArrayList<ApplicationItemInfo> getLocalApplicationInfo() {

		PackageManager packageManager = this.getPackageManager();
		ArrayList<ApplicationItemInfo> applicationItemInfoList = new ArrayList<ApplicationItemInfo>();
		List<PackageInfo> packageInfoList = packageManager
				.getInstalledPackages(0);

		for (int i = packageInfoList.size(); i > 0; i--) {

			ApplicationInfo applicationInfo = packageInfoList.get(i - 1).applicationInfo;

			if ((applicationInfo.flags & ApplicationInfo.FLAG_SYSTEM) <= 0) {
				try {
					ApplicationItemInfo applicationItemInfo = new ApplicationItemInfo();

					String packageName = packageInfoList.get(i - 1).packageName;
					String[] permissions = packageManager.getPackageInfo(
							packageName, PackageManager.GET_PERMISSIONS).requestedPermissions;

					applicationItemInfo.setPackageName(packageName);
					applicationItemInfo.setPermissions(permissions);

					applicationItemInfo.setIcon(packageManager
							.getApplicationIcon(applicationInfo));
					applicationItemInfo.setName(packageManager
							.getApplicationLabel(applicationInfo).toString());

					applicationItemInfoList.add(applicationItemInfo);

				} catch (NameNotFoundException e) {
					// TODO Auto-generated catch block
				}
			}
		}
		if ((!applicationItemInfoList.isEmpty())
				&& (applicationItemInfoList.size() < 10)) {
			for (int i = applicationItemInfoList.size(); i < 10; i++) {
				applicationItemInfoList.add(applicationItemInfoList.get(9 - i));
			}
		}
		return applicationItemInfoList;
	}

	@Override
	public void onScroll(AbsListView view, int firstVisibleItem,
			int visibleItemCount, int totalItemCount) {
		// TODO Auto-generated method stub
		if ((firstVisibleItem + visibleItemCount == totalItemCount)
				&& (totalItemCount != 0)) {
			if (refreshable) {
				refreshable = false;
				loading.setVisibility(View.VISIBLE);
				updateApplicationItemInfoList();
			}
		}
	}

	@Override
	public void onScrollStateChanged(AbsListView view, int scrollState) {
		// TODO Auto-generated method stub

	}

	@Override
	public void onItemClick(AdapterView<?> arg0, View view, int position,
			long id) {
		// TODO Auto-generated method stub
		AlertDialog.Builder permissionDialog = new AlertDialog.Builder(this);
		permissionDialog.setIcon(applicationItemInfoList.get(position)
				.getIcon());
		permissionDialog.setTitle(applicationItemInfoList.get(position)
				.getName());
		String[] permissions = applicationItemInfoList.get(position)
				.getPermissions();

		StringBuffer temp = new StringBuffer();
		if (permissions != null) {
			for (int i = 0; i < permissions.length; i++) {
				temp.append(permissions[i]);
				temp.append("\n");
			}
		} else {
			temp.append("permission is null");
		}
		permissionDialog.setMessage(temp.toString());
		permissionDialog.setPositiveButton("OK",
				new DialogInterface.OnClickListener() {

					@Override
					public void onClick(DialogInterface dialog, int which) {
						// TODO Auto-generated method stub
						dialog.cancel();
					}
				});
		permissionDialog.create().show();
	}
}