Question

我正在尝试将一些简单文本保存在文件中，然后再阅读。我已经在相同的应用程序中创建了文件，但工作正常，但由于某种原因，我得到了一个当我尝试使用openFileInput（）方法时FileNotFoundException。

private static final String COOKIE = "account_cookie.txt";    

public void saveAccountCookie(String accountId, String expiryDate) {
    try {
        PrintWriter pw = new PrintWriter(openFileOutput(COOKIE, MODE_PRIVATE));
        pw.write(accountId + " " + expiryDate);
        pw.close();
    } catch (FileNotFoundException e) {
        e.printStackTrace();
    }
}



public boolean cookieValid() {
    try {
        InputStreamReader isr = new InputStreamReader(openFileInput(COOKIE));
        BufferedReader br = new BufferedReader(isr);
        String[] cookie = br.readLine().split(" ");
        br.close();
        if (checkExpiry(cookie[1])) {
            return true;
        }
        checkTrialRequest(cookie[0]);
        return false;
    } catch (FileNotFoundException e) {
        return false;
    } catch (IOException e) {
        return false;
    }
}

这些方法是从AsyncTask

调用的

Answer 1

首先在源文件夹中创建一个Application Class，这样你就可以为应用程序本身处理General Stuff这样的东西

public class MyApp extends Application {
    private static MyApp instance;

    public void onCreate() {
        super.onCreate();
    }


    public MyApp() {
        super();
        instance = this;
    }

    public static MyApp getInstance() {
        return (instance == null) ? instance = new MyApp() : instance;
    }
}

然后尝试这种方式

public void saveAccountCookie(String accountId, String expiryDate) {
    try {
        FileOutputStream fos = MyApp.getInstance().getBaseContext().openFileOutput(COOKIE, Context.MODE_PRIVATE);
        PrintWriter pw = new PrintWriter(fos);
        pw.write(accountId + " " + expiryDate);
        pw.close();
    } catch (FileNotFoundException e) {
        e.printStackTrace();
    }
}


public boolean cookieValid() {
    try {
        FileInputStream fis = MyApp.getInstance().getBaseContext().openFileInput(COOKIE);
        InputStreamReader isr = new InputStreamReader(fis);
        BufferedReader br = new BufferedReader(isr);
        String[] cookie = br.readLine().split(" ");
        br.close();
        if (checkExpiry(cookie[1])) {
            return true;
        }
        checkTrialRequest(cookie[0]);
        return false;
    } catch (FileNotFoundException e) {
        return false;
    } catch (IOException e) {
        return false;
    }
}

告诉我这种方式是否有效。：）

无法使用openFileOutput写入文件

1 个答案: