android异步扫描SD卡

package allen.test; import java.io.File; import java.util.ArrayList; import java.util.List; import android.app.Activity; import android.app.ProgressDialog; import android.content.Intent; import android.os.AsyncTask; import android.os.Bundle; import android.os.Environment; import android.view.View; import android.widget.Button; import android.widget.EditText; import android.widget.Toast; public class TestActivity extends Activity { static List<File> txtList;// 文件列表 EditText editText; public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.main); this.setTitle("异步加载DEMO(扫描SD卡指定后缀文件)"); Button btnPhoto = (Button) findViewById(R.id.button); editText = (EditText) findViewById(R.id.edittext); txtList = new ArrayList<File>(); btnPhoto.setOnClickListener(new View.OnClickListener() { public void onClick(View v) { new AsyncTask<Integer, Integer, String[]>() { private ProgressDialog dialog; protected void onPreExecute() { dialog = ProgressDialog.show(TestActivity.this, "", "正在扫描SD卡,请稍候...."); super.onPreExecute(); } protected String[] doInBackground(Integer... params) { if (!android.os.Environment.getExternalStorageState() .equals(android.os.Environment.MEDIA_MOUNTED)) { } else { if (!editText.getText().toString().equals("")) { GetFiles(Environment .getExternalStorageDirectory()); } } return null; } protected void onPostExecute(String[] result) { dialog.dismiss(); if (editText.getText().toString().equals("")) { Toast.makeText(TestActivity.this, "请输入有效信息", Toast.LENGTH_SHORT).show(); } else { Toast.makeText(TestActivity.this, "扫描完毕", Toast.LENGTH_LONG).show(); Intent in = new Intent(); in.setClass(TestActivity.this, ListOk.class); TestActivity.this.startActivity(in); } super.onPostExecute(result); } }.execute(0); } }); } /** * 获取文件列表 * * @param filePath */ public void GetFiles(File filePath) { File[] files = filePath.listFiles(); if (files != null) { for (int i = 0; i < files.length; i++) { if (files[i].isDirectory()) { GetFiles(files[i]); } else { if (files[i].getName().toLowerCase() .endsWith("." + editText.getText().toString())) { txtList.add(files[i]); } } } } } }