java - 如何在 Android 中保存数据？

Question

这个问题已经有答案了:

Best way to store data in Android [closed] (3 个回答)

已关闭 6 年前。

所以我制作了一个 Cookie Clicker 应用程序来帮助我开始学习如何使用 Android Studio 在 Android 上编程。
但我需要一种方法来保存玩家拥有的 cookie 数量，这样当他退出游戏并回来时，它们就会被保存。
这是我当前的代码:

MainActivity.java:

package com.android.example;

import android.media.MediaPlayer;
import android.os.Bundle;
import android.support.v7.app.AppCompatActivity;
import android.view.View;
import android.widget.ImageButton;
import android.widget.TextView;

public class MainActivity extends AppCompatActivity {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

            /* Sound */
        final MediaPlayer cookieSound = MediaPlayer.create(this, R.raw.cookie_eat_short);

        ImageButton playCookieSound = (ImageButton) this.findViewById(R.id.cookie_button);

        playCookieSound.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                cookieSound.start();
                /* End of Sound */

                /* The following lines add 1 to the score and then display it. */
                scoreCookies++;
                display(scoreCookies);
            }

        });

    }

    /*  Initializing the score to 0
    * This is also what I want to change, make it set the score to the saved score.*/
    int scoreCookies = 0;

    /* This method displays the score on the screen. */
    private void display(int number) {
        TextView quantityTextView = (TextView) findViewById(R.id.score_text_view);
        quantityTextView.setText("" + number);
    }
}

activity_main.xml:

<ImageButton
    android:id="@+id/cookie_button"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:layout_alignParentBottom="true"
    android:layout_alignParentLeft="true"
    android:layout_alignParentStart="true"
    android:layout_marginBottom="124dp"
    android:background="@android:color/transparent"
    android:scaleType="fitStart"
    app:srcCompat="@drawable/cookiepic" />

<TextView
    android:id="@+id/score_text_view"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:layout_alignParentBottom="true"
    android:layout_centerHorizontal="true"
    android:layout_marginBottom="52dp"
    android:text="0"
    android:textSize="42sp"
    android:textAppearance="@style/TextAppearance.AppCompat.Headline" />

预先感谢您帮助我:)

Answer 1

您可以使用共享首选项来保存少量数据。

写

SharedPreferences sharedPref = getActivity().getPreferences(Context.MODE_PRIVATE);
SharedPreferences.Editor editor = sharedPref.edit();
editor.putInt(getString(R.string.saved_high_score), newHighScore);
editor.commit();

阅读

SharedPreferences sharedPref = getActivity().getPreferences(Context.MODE_PRIVATE);
int defaultValue = getResources().getInteger(R.string.saved_high_score_default);
long highScore = sharedPref.getInt(getString(R.string.saved_high_score), defaultValue);