写入文件然后读取，然后再像一个字符串一样保存内容

Question

我想写进一个文件，然后，我想把内容保存在一个 StringBuffer 里面。最后再通过一个 TextView显示，但是什么也不显示。

public class MainActivity extends Activity {
String finall;
@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);
    String FILENAME = "hello_file";
    String string = "hello world!";
    FileOutputStream fos;
    try
    {
        fos = openFileOutput(FILENAME, Context.MODE_PRIVATE);
        fos.write(string.getBytes());
        fos.close();
    } 
    catch (FileNotFoundException e) { e.printStackTrace(); } 
    catch (IOException e) { e.printStackTrace(); }



    FileInputStream in = null;
    try
    {
        in = openFileInput("hello_file.txt");
        StringBuffer fileContent = new StringBuffer("");

        byte[] buffer = new byte[1024];

        while(in.read(buffer) != -1)
        {
            fileContent.append(new String(buffer));
        }
        finall = fileContent.toString();
    }
    catch (FileNotFoundException e) { e.printStackTrace(); } 
    catch (IOException e) { e.printStackTrace(); }

    TextView text = (TextView)findViewById(R.id.mehmet);
    text.setText(finall);
}
}

Answer 1

读写文件的路径改为SD卡中，并加上写SD卡权限试试