读写内部存储的文件数据

    把  XXX.txt文件 写入/读取  在data/data/包  目录下面。

/** 读写内部存储的文件数据 */
        findViewById(R.id.btnWrite).setOnClickListener(
                new View.OnClickListener() {
                    @Override
                    public void onClick(View v) {
                        try {
                            FileOutputStream fas = openFileOutput("text",
                                    Context.MODE_PRIVATE);
                            OutputStreamWriter asw = new OutputStreamWriter(
                                    fas, "UTF-8");
                            asw.write(et.getText().toString());
                            asw.flush();
                            fas.flush();
                            asw.close();
                            fas.close();
                            Toast.makeText(getApplicationContext(), "写入完成。",
                                    Toast.LENGTH_SHORT).show();
                        } catch (FileNotFoundException e) {
                            e.printStackTrace();
                        } catch (UnsupportedEncodingException e) {
                            e.printStackTrace();
                        }
                    }
                });
        findViewById(R.id.btnRead).setOnClickListener(
                new View.OnClickListener() {
                    @Override
                    public void onClick(View v) {
                        try {
                            FileInputStream fis = openFileInput("text");
                            InputStreamReader is = new InputStreamReader(fis,
                                    "UTF-8");
                            char input[] = new char[fis.available()];
                            is.read(input);
                            is.close();
                            fis.close();
                            String readed = new String(input);
                            show.setText(readed);
                        } catch (FileNotFoundException e) {
                            e.printStackTrace();
                        } catch (IOException e) {
                            e.printStackTrace();
                        }
                    }
                });