增加本地存储类

app/src/main/java/com/bgycc/smartcanteen/Storage/PayStorage.java

+package com.bgycc.smartcanteen.Storage;
+
+import android.content.Context;
+import org.json.JSONArray;
+import org.json.JSONException;
+import org.json.JSONObject;
+
+public class PayStorage extends Storage {
+
+    static final String TAG = PayStorage.class.getSimpleName();
+    enum Key {
+        PAY_LIST
+    }
+
+    static PayStorage sInstance;
+
+    public static void initialize(Context context) {
+        sInstance = new PayStorage(context);
+    }
+
+    public static PayStorage getInstance() {
+        return sInstance;
+    }
+
+    JSONArray mPayList = new JSONArray();
+
+    PayStorage(Context context) {
+        super(TAG, context);
+        try {
+            String tmp = mSharedPreferences.getString(Key.PAY_LIST.name(), "[]");
+            mPayList = new JSONArray(tmp);
+        } catch (JSONException e) {
+            e.printStackTrace();
+        }
+    }
+
+    public synchronized void add(JSONObject payInfo) {
+        mPayList.put(payInfo);
+    }
+
+    public synchronized JSONArray getPayList() {
+        return mPayList;
+    }
+
+    public synchronized void savePayList() {
+        mSharedPreferences.edit()
+                .putString(Key.PAY_LIST.name(), mPayList.toString())
+                .apply();
+    }
+
+    public synchronized void clearPayList() {
+        mPayList = new JSONArray();
+        mSharedPreferences.edit()
+                .remove(Key.PAY_LIST.name())
+                .apply();
+    }
+}

app/src/main/java/com/bgycc/smartcanteen/Storage/Storage.java

+package com.bgycc.smartcanteen.Storage;
+
+import android.content.Context;
+import android.content.SharedPreferences;
+
+public abstract class Storage {
+
+    SharedPreferences mSharedPreferences;
+
+    protected Storage(String name, Context context) {
+        mSharedPreferences = context.getSharedPreferences(name, Context.MODE_PRIVATE);
+    }
+
+}