java - Android模拟器中的问题写入文件问题

Question

我正在尝试使用以下代码将一些简单数据写入外部存储。我在这里遗漏了一些东西，但不确定是什么。谢谢

罗布达

public class TimeCard extends Activity {
    /** Called when the activity is first created. */
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);

        final Button button = (Button) findViewById(R.id.Button01);
        final EditText edittext = (EditText) findViewById(R.id.EditText01);
        final EditText edittext1 = (EditText)findViewById(R.id.EditText02);
        final EditText edittext2 = (EditText)findViewById(R.id.EditText03);
        final EditText edittext3 = (EditText)findViewById(R.id.EditText04);
        final String inputString = edittext + "/n" + edittext1 + "/n"+  edittext2 + "/n" + edittext3;
        button.setOnClickListener(new OnClickListener() {
            public void onClick(View v) {               
              //Do it
              CreateFile(inputString);
              //Let them know it
              Toast.makeText(TimeCard.this, "You are Clocked In", Toast.LENGTH_LONG).show();
            }


        });
    }
    //Write to SD Card
 public void CreateFile(String InputString){        

     File SDCard = Environment.getExternalStorageDirectory();  
     String FILENAME = SDCard + "/time_card.txt";

        FileOutputStream fos = null;
        try {
            fos = openFileOutput(FILENAME, Context.MODE_WORLD_READABLE);
        } catch (FileNotFoundException e) {

            e.printStackTrace();
        }
        try {
            fos.write(InputString.getBytes());
        } catch (IOException e) {

            e.printStackTrace();
        }
        try {
            fos.close();
        } catch (IOException e) {

            e.printStackTrace();
        }
        }
   }

Answer 1

我尝试运行您的代码，错误是由您使用openFileOutput(String name, int mode) 方法的方式引起的。查看 LogCat 内部，我可以看到以下异常:

java.lang.IllegalArgumentException: File /mnt/sdcard/time_card.txt contains a path separator

这为我指出了 this question 的答案方向，这也可能会解决您的问题:

Context.openFileOutput is meant to be used for creating files private to your application. They go in your app's private data directory. You supply a name, not a path

documentation for openFileOutput还指出了有关函数的名称参数的信息:

The name of the file to open; can not contain path separators.

为了将来引用，当您遇到此类问题时，学习如何使用您可用的工具(例如 LogCat)是绝对重要的。没有它们，您将很难找出问题所在。因此，我建议您阅读一些有关如何执行此操作的信息。