public class DataActivity extends Activity {

    private EditText filenameText;

    private EditText contentText;

    private TextView resultView;

    private static final String TAG = "DataActivity";

    /** Called when the activity is first created. */

    @Override

        public void onCreate(Bundle savedInstanceState) {

        super.onCreate(savedInstanceState);

        setContentView(R.layout.main);

        filenameText = (EditText) this.findViewById(R.id.filename);

        contentText = (EditText) this.findViewById(R.id.content);

        resultView = (TextView) this.findViewById(R.id.result);

        String filename = filenameText.getText().toString();

        Button button = (Button) this.findViewById(R.id.button);

        Button showButton = (Button) this.findViewById(R.id.showButton);

        button.setOnClickListener(listener);

        showButton.setOnClickListener(listener);

    }  

    private View.OnClickListener listener = new View.OnClickListener() {

        @Override

            public void onClick(View v) {

            Button button = (Button) v;

            String filename = filenameText.getText().toString();

            switch(button.getId()){

            case R.id.button://如果是保存按钮

                int resId = R.string.success;  

                String content = contentText.getText().toString();

                File file = new File(Environment.getExternalStorageDirectory(),filename);

                if(Environment.getExternalStorageState().equals(Environment.MEDIA_MOUNTED)){

                    try {

                        //OutputStream outStream = DataActivity.this.openFileOutput(filename, Context.MODE_WORLD_WRITEABLE+Context.MODE_WORLD_READABLE);

                        //四中操作模式

                        //Context.MODE_PRIVATE=0 覆盖、私有

                        //Context.MODE_APPEND=32768追加、私有

                        //Context.MODE_WORLD_READABLE=1其他的程序可以访问

                        //Context.MODE_WORLD_WRITEABLE=2

                        //Environment.getExternalStorageDirectory()==new file("/sdcard")  

                        FileOutputStream outStream = new FileOutputStream(file);

                        try {

                            FileService.save(outStream, content);

                        } catch (Exception e) {

                            Log.e(TAG, e.toString());

                            resId = R.string.error;

                        }

                    } catch (FileNotFoundException e) {

                        Log.e(TAG, e.toString());

                        resId = R.string.error;

                    }

                    Toast.makeText(DataActivity.this, resId, Toast.LENGTH_LONG).show();

                }

                else{

                    Toast.makeText(DataActivity.this,"SD卡不存在或者写保护", Toast.LENGTH_LONG).show();

                }

                break;

            case R.id.showButton://如果是显示按钮

                try {

                    InputStream inStream = DataActivity.this.openFileInput(filename);

                    String text = FileService.read(inStream);

                    resultView.setText(text);

                } catch (Exception e) {

                    Log.e(TAG, e.toString());

                    resId = R.string.error;

                    Toast.makeText(DataActivity.this, "读取失败", Toast.LENGTH_LONG).show();

                }  

                break;

            }

        }

    };  

}