Android TextReader

package com.jim8581.txtReader; import java.io.File; import java.util.ArrayList; import java.util.List; import android.app.AlertDialog; import android.app.Dialog; import android.app.ListActivity; import android.content.DialogInterface; import android.content.Intent; import android.os.Bundle; import android.view.Menu; import android.view.MenuInflater; import android.view.MenuItem; import android.view.View; import android.widget.ArrayAdapter; import android.widget.ListView; import com.jim8581.txtReader.R; /*展现全部文件的Activity*/ public class ListAllFileActivity extends ListActivity { @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.filelist); initFileList(); } private void initFileList() { File path = android.os.Environment.getExternalStorageDirectory(); File[] f = path.listFiles(); fill(f); } @Override public boolean onCreateOptionsMenu(Menu menu) { MenuInflater inflater = this.getMenuInflater(); inflater.inflate(R.menu.menu, menu); menu.removeItem(R.id.gb2312); menu.removeItem(R.id.utf8); return true; } @Override public boolean onOptionsItemSelected(MenuItem item) { switch (item.getItemId()) { case R.id.about: doAbout(); break; default: break; } return super.onOptionsItemSelected(item); } //弹出关于框 private void doAbout() { Dialog dialog = new AlertDialog.Builder(ListAllFileActivity.this).setTitle( R.string.aboutTitle).setMessage(R.string.aboutInfo) .setPositiveButton(R.string.aboutOK, new DialogInterface.OnClickListener() { public void onClick( DialogInterface dialoginterface, int i) { // 按钮事件 } }).create(); dialog.show(); } @Override protected void onListItemClick(ListView l, View v, int position, long id) { Intent intent = new Intent(ListAllFileActivity.this, ViewFile.class); bundle = new Bundle(); File file = fileNameList.get(position); if (file.isDirectory()) { File[] f = file.listFiles(); fill(f); } else { bundle.putString(fileNameKey, file.getAbsolutePath()); intent.putExtras(bundle); startActivityForResult(intent, 0); } } // 读取文件列表,并设置listview private void fill(File[] files) { fileNameList = new ArrayList<File>(); for (File file : files) { if (isValidFileOrDir(file)) { fileNameList.add(file); } } ArrayAdapter<String> adapter = new ArrayAdapter<String>(this, android.R.layout.simple_list_item_1, fileToStrArr(fileNameList)); setListAdapter(adapter); } /*检查是否为合法的文件名，或者是否为路径*/ private boolean isValidFileOrDir(File file) { if (file.isDirectory()) { return true; } else { String fileName = file.getName().toLowerCase(); if (fileName.endsWith(".txt")) { return true; } } return false; } private String[] fileToStrArr(List<File> fl) { ArrayList<String> fnList = new ArrayList<String>(); for (int i = 0; i < fl.size(); i++) { String nameString = fl.get(i).getName(); fnList.add(nameString); } return fnList.toArray(new String[0]); } /*文件列表*/ private List<File> fileNameList; private Bundle bundle; private String fileNameKey = "fileName"; }