將數據保存在SD卡上

Question

我正在編寫一個小游戲，我想在SD卡上保存得分和音量（已啟用或已禁用），這兩個函數的代碼是：

public static void load(FileIO files) {
    BufferedReader in = null;
    try {
        in = new BufferedReader(new InputStreamReader(
                files.readFile(".save")));
        soundEnabled = Boolean.parseBoolean(in.readLine());
        for (int i = 0; i < 5; i++) {
            highscores[i] = Integer.parseInt(in.readLine());
        }
    } catch (IOException e) {
        // :( It's ok we have defaults
    } catch (NumberFormatException e) {
        // :/ It's ok, defaults save our day
    } finally {
        try {
            if (in != null)
                in.close();
        } catch (IOException e) {
        }
    }
}

// ------------------------

public static void save(FileIO files) {
    BufferedWriter out = null;
    try {
        out = new BufferedWriter(new OutputStreamWriter(
                files.writeFile(".save")));
        out.write(Boolean.toString(soundEnabled));
        for (int i = 0; i < 5; i++) {
            out.write(Integer.toString(highscores[i]));
        }

    } catch (IOException e) {
    } finally {
        try {
            if (out != null)
                out.close();
        } catch (IOException e) {
        }
    }
}

當程序運行時，此代碼可以，但是如果我重新啟動設備，分數會丟失..您知道為什么嗎？

謝謝！！

ps：FileIO類是：

  public class AndroidFileIO implements FileIO {
    Context context;
    AssetManager assets;
    String externalStoragePath;

    public AndroidFileIO(Context context) {
       this.context = context;
       this.assets = context.getAssets();
       this.externalStoragePath = Environment.getExternalStorageDirectory()
            .getAbsolutePath() + File.separator;
    }

    public InputStream readAsset(String fileName) throws IOException {
       return assets.open(fileName);
    }

    public InputStream readFile(String fileName) throws IOException {
       return new FileInputStream(externalStoragePath + fileName);
    }

    public OutputStream writeFile(String fileName) throws IOException {
       return new FileOutputStream(externalStoragePath + fileName);
    }

    public SharedPreferences getPreferences() {
       return PreferenceManager.getDefaultSharedPreferences(context);
    }
 }

Answer 1

這里有兩個問題。 首先，out.write不會在每個調用的末尾插入換行符，您必須手動執行。 所以發生的事情是，當您在cal中執行readline來解析布爾值時，您實際上正在使用文件中的所有數據。 其次，您需要在離開該函數之前刷新並關閉文件，以確保您沒有在緩沖區中保留任何數據。

這是應該工作的保存重寫：

public static void save(FileIO files) {
BufferedWriter out = null;
try {
    out = new BufferedWriter(new OutputStreamWriter(
            files.writeFile(".mrnom")));
    out.write(Boolean.toString(soundEnabled));
    out.write("\n");
    for (int i = 0; i < 5; i++) {
        out.write(Integer.toString(highscores[i]));
        out.write("\n");

    }
    out.flush();
    out.close();
} catch (IOException e) {
} finally {
    try {
        if (out != null)
            out.close();
    } catch (IOException e) {

    }
}
}

Answer 2

我是第一次編程，但是iv使用共享的首選項解決了這個問題。 這樣，您可以避免在更新應用程序時丟失數據。