android中File文件的读的实现

public class MainActivity extends Activity {private TextView tv;@Overrideprotected void onCreate(Bundle savedInstanceState) {super.onCreate(savedInstanceState);setContentView(R.layout.activity_main);tv = (TextView) findViewById(R.id.tv);findViewById(R.id.btn).setOnClickListener(new OnClickListener() {@Overridepublic void onClick(View v) {// 文本设为空tv.setText("");// 找文件String path = Environment.getExternalStorageDirectory().getAbsolutePath() + "/poem.txt";// 用字符流读取–try {FileReader fr = new FileReader(path);BufferedReader br = new BufferedReader(fr);while (true) {String msg = br.readLine();if (msg == null) {break;}tv.append(msg);}} catch (FileNotFoundException e) {e.printStackTrace();} catch (IOException e) {e.printStackTrace();}}});}}