滑动显示首字母的ListView

package com.mark; import java.lang.reflect.Field; import android.app.Activity; import android.app.Dialog; import android.content.Context; import android.content.Intent; import android.graphics.PixelFormat; import android.graphics.drawable.Drawable; import android.net.Uri; import android.os.Bundle; import android.os.Handler; import android.util.Log; import android.view.LayoutInflater; import android.view.View; import android.view.ViewGroup.LayoutParams; import android.view.WindowManager; import android.widget.AbsListView; import android.widget.AdapterView; import android.widget.AdapterView.OnItemClickListener; import android.widget.ImageView; import android.widget.LinearLayout; import android.widget.ListView; import android.widget.TextView; /** * @author Sodino E-mail:sodinoopen@hotmail.com * @version Time：2011-5-1 下午03:22:00 */ public class MainActivity extends Activity implements ListView.OnScrollListener, OnItemClickListener, android.view.View.OnClickListener { private Handler handler; private DisapearThread disapearThread; /** 标识List的滚动状态。 */ private int scrollState; private ListAdapter listAdapter; private ListView listMain; private TextView txtOverlay; private WindowManager windowManager; /** Called when the activity is first created. */ public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.main); handler = new Handler(); // 初始化首字母悬浮提示框 txtOverlay = (TextView) LayoutInflater.from(this).inflate(R.layout.popup_char_hint, null); txtOverlay.setVisibility(View.INVISIBLE); WindowManager.LayoutParams lp = new WindowManager.LayoutParams(LayoutParams.WRAP_CONTENT, LayoutParams.WRAP_CONTENT, WindowManager.LayoutParams.TYPE_APPLICATION, WindowManager.LayoutParams.FLAG_NOT_FOCUSABLE | WindowManager.LayoutParams.FLAG_NOT_TOUCHABLE, PixelFormat.TRANSLUCENT); windowManager = (WindowManager) getSystemService(Context.WINDOW_SERVICE); windowManager.addView(txtOverlay, lp); // 初始化ListAdapter listAdapter = new ListAdapter(this, stringArr, this); listMain = (ListView) findViewById(R.id.listInfo); listMain.setOnItemClickListener(this); listMain.setOnScrollListener(this); listMain.setAdapter(listAdapter); changeFastScrollerDrawable(listMain); disapearThread = new DisapearThread(); } /** 更改指定ListView的快速滚动条图标。 */ private void changeFastScrollerDrawable(ListView list) { try { Field f = AbsListView.class.getDeclaredField("mFastScroller"); f.setAccessible(true); Object obj = f.get(list); f = f.getType().getDeclaredField("mThumbDrawable"); f.setAccessible(true); Drawable drawable = (Drawable) f.get(obj); drawable = getResources().getDrawable(R.drawable.fast_scroller_img); f.set(obj, drawable); } catch (Exception e) { throw new RuntimeException(e); } } /** ListView.OnScrollListener */ public void onScroll(AbsListView view, int firstVisibleItem, int visibleItemCount, int totalItemCount) { // 以中间的ListItem为标准项。 txtOverlay.setText(String.valueOf(stringArr[firstVisibleItem + (visibleItemCount >> 1)] .charAt(0))); } /** ListView.OnScrollListener */ public void onScrollStateChanged(AbsListView view, int scrollState) { this.scrollState = scrollState; if (scrollState == ListView.OnScrollListener.SCROLL_STATE_IDLE) { handler.removeCallbacks(disapearThread); // 提示延迟1.5s再消失 boolean bool = handler.postDelayed(disapearThread, 1500); Log.d("ANDROID_INFO", "postDelayed=" + bool); } else { txtOverlay.setVisibility(View.VISIBLE); } } /** OnItemClickListener */ public void onItemClick(AdapterView<?> parent, View view, int position, long id) { String personalName = stringArr[position]; String url = ListAdapter.URL_PREFIX + personalName.replace(" ", "%20"); showInfo(personalName, url); } /** * View.OnClickListener <br/> * 点击“咧牙”图片。<br/> */ public void onClick(View view) { if (view instanceof ImageView) { // "咧牙"图标 int position = ((Integer) view.getTag()).intValue(); ActionItem actionAdd = new ActionItem(getResources().getDrawable(R.drawable.icon_info), "Info", this); ActionItem actionWeb = new ActionItem(getResources().getDrawable(R.drawable.icon_web), "Web", this); ActionItem actionEMail = new ActionItem(getResources().getDrawable( R.drawable.icon_email), "Email", this); QuickActionBar qaBar = new QuickActionBar(view, position); qaBar.setEnableActionsLayoutAnim(true); qaBar.addActionItem(actionAdd); qaBar.addActionItem(actionWeb); qaBar.addActionItem(actionEMail); qaBar.show(); } else if (view instanceof LinearLayout) { // ActionItem组件 LinearLayout actionsLayout = (LinearLayout) view; QuickActionBar bar = (QuickActionBar) actionsLayout.getTag(); bar.dismissQuickActionBar(); int listItemIdx = bar.getListItemIndex(); TextView txtView = (TextView) actionsLayout.findViewById(R.id.qa_actionItem_name); String actionName = txtView.getText().toString(); String personalName = stringArr[listItemIdx]; String url = ListAdapter.URL_PREFIX + personalName.replace(" ", "%20"); if (actionName.equals("Info")) { showInfo(personalName, url); } else if (actionName.equals("Web")) { go2Web(url); } else if (actionName.equals("Email")) { sendEMail(personalName, url); } } } public void showInfo(String name, String url) { String content = "Name:" + name + "\n"// + "URL:" + url// ; Dialog dialog = new Dialog(this); dialog.setContentView(R.layout.info_dialog); dialog.setTitle("Personal Information"); TextView text = (TextView) dialog.findViewById(R.id.text); text.setText(content); ImageView image = (ImageView) dialog.findViewById(R.id.image); image.setImageResource(R.drawable.icon_info); dialog.show(); } private void go2Web(String url) { Intent intent = new Intent(Intent.ACTION_VIEW, Uri.parse(url)); startActivity(intent); } private void sendEMail(String name, String url) { Intent mailIntent = new Intent(Intent.ACTION_SEND); // 设置邮件类型为纯文本，即为所有可见字符与一些简单的控制符的组合。 mailIntent.setType("plain/text"); // 收件人地址 String[] arrReceiver = { "sodinoopen@hotmail.com" }; // 抄送地址 String[] arrCc = { "sodinoopen@hotmail.com" }; // 密送地址 String[] arrBcc = { "sodinoopen@hotmail.com", "sodinoopen@hotmail.com" }; String mailSubject = "This is a mail send by list demo"; String mailBody = "Hello everyone, I think the my demo is very good, haha. thanks."; // 指定要添加的附件的完整路径 String attachPath = "file:///sdcard/Test.apk"; mailIntent.putExtra(Intent.EXTRA_EMAIL, arrReceiver); mailIntent.putExtra(Intent.EXTRA_CC, arrCc); mailIntent.putExtra(Intent.EXTRA_BCC, arrBcc); mailIntent.putExtra(Intent.EXTRA_SUBJECT, mailSubject); mailIntent.putExtra(Intent.EXTRA_TEXT, mailBody); mailIntent.putExtra(Intent.EXTRA_STREAM, Uri.parse(attachPath)); // 过滤Intent并启动GMail界面，之后点击Send即可将邮件发送出去。 Intent finalIntent = Intent.createChooser(mailIntent, "Mail Sending..."); startActivity(finalIntent); } private class DisapearThread implements Runnable { public void run() { // 避免在1.5s内，用户再次拖动时提示框又执行隐藏命令。 if (scrollState == ListView.OnScrollListener.SCROLL_STATE_IDLE) { txtOverlay.setVisibility(View.INVISIBLE); } } } public void onDestroy() { super.onDestroy(); // 将txtOverlay删除。 txtOverlay.setVisibility(View.INVISIBLE); windowManager.removeView(txtOverlay); } private String[] stringArr = { "Abbaye de Belloc", "Abbaye du Mont des Cats", "Abertam", "Abondance", "Ackawi", "Acorn", "Adelost", "Affidelice au Chablis", "Afuega'l Pitu", "Airag", "Airedale", "Aisy Cendre", "Allgauer Emmentaler", "Alverca",