商城之购物车

1.购物车数据存储器

1.把购物车数据存储到本地，转换成json字符串使用SP存储

2.PreferencesUtils

package cniao5.com.cniao5shop.utils;import android.content.Context;import android.content.SharedPreferences;/** * PreferencesUtils, easy to get or put data * <ul> * <strong>Preference Name</strong> * <li>you can change preference name by {@link #PREFERENCE_NAME}</li> * </ul> * <ul> * <strong>Put Value</strong> * <li>put string {@link #putString(Context, String, String)}</li> * <li>put int {@link #putInt(Context, String, int)}</li> * <li>put long {@link #putLong(Context, String, long)}</li> * <li>put float {@link #putFloat(Context, String, float)}</li> * <li>put boolean {@link #putBoolean(Context, String, boolean)}</li> * </ul> * <ul> * <strong>Get Value</strong> * <li>get string {@link #getString(Context, String)}, {@link #getString(Context, String, String)}</li> * <li>get int {@link #getInt(Context, String)}, {@link #getInt(Context, String, int)}</li> * <li>get long {@link #getLong(Context, String)}, {@link #getLong(Context, String, long)}</li> * <li>get float {@link #getFloat(Context, String)}, {@link #getFloat(Context, String, float)}</li> * <li>get boolean {@link #getBoolean(Context, String)}, {@link #getBoolean(Context, String, boolean)}</li> * </ul> *  */public class PreferencesUtils {    public static String PREFERENCE_NAME = "Cniao_Pref_Common";    /**     * put string preferences     *      * @param context     * @param key The name of the preference to modify     * @param value The new value for the preference     * @return True if the new values were successfully written to persistent storage.     */    public static boolean putString(Context context, String key, String value) {        SharedPreferences settings = context.getSharedPreferences(PREFERENCE_NAME, Context.MODE_PRIVATE);        SharedPreferences.Editor editor = settings.edit();        editor.putString(key, value);        return editor.commit();    }    /**     * get string preferences     *      * @param context     * @param key The name of the preference to retrieve     * @return The preference value if it exists, or null. Throws ClassCastException if there is a preference with this     *         name that is not a string     * @see #getString(Context, String, String)     */    public static String getString(Context context, String key) {        return getString(context, key, null);    }    /**     * get string preferences     *      * @param context     * @param key The name of the preference to retrieve     * @param defaultValue Value to return if this preference does not exist     * @return The preference value if it exists, or defValue. Throws ClassCastException if there is a preference with     *         this name that is not a string     */    public static String getString(Context context, String key, String defaultValue) {        SharedPreferences settings = context.getSharedPreferences(PREFERENCE_NAME, Context.MODE_PRIVATE);        return settings.getString(key, defaultValue);    }    /**     * put int preferences     *      * @param context     * @param key The name of the preference to modify     * @param value The new value for the preference     * @return True if the new values were successfully written to persistent storage.     */    public static boolean putInt(Context context, String key, int value) {        SharedPreferences settings = context.getSharedPreferences(PREFERENCE_NAME, Context.MODE_PRIVATE);        SharedPreferences.Editor editor = settings.edit();        editor.putInt(key, value);        return editor.commit();    }    /**     * get int preferences     *      * @param context     * @param key The name of the preference to retrieve     * @return The preference value if it exists, or -1. Throws ClassCastException if there is a preference with this     *         name that is not a int     * @see #getInt(Context, String, int)     */    public static int getInt(Context context, String key) {        return getInt(context, key, -1);    }    /**     * get int preferences     *      * @param context     * @param key The name of the preference to retrieve     * @param defaultValue Value to return if this preference does not exist     * @return The preference value if it exists, or defValue. Throws ClassCastException if there is a preference with     *         this name that is not a int     */    public static int getInt(Context context, String key, int defaultValue) {        SharedPreferences settings = context.getSharedPreferences(PREFERENCE_NAME, Context.MODE_PRIVATE);        return settings.getInt(key, defaultValue);    }    /**     * put long preferences     *      * @param context     * @param key The name of the preference to modify     * @param value The new value for the preference     * @return True if the new values were successfully written to persistent storage.     */    public static boolean putLong(Context context, String key, long value) {        SharedPreferences settings = context.getSharedPreferences(PREFERENCE_NAME, Context.MODE_PRIVATE);        SharedPreferences.Editor editor = settings.edit();        editor.putLong(key, value);        return editor.commit();    }    /**     * get long preferences     *      * @param context     * @param key The name of the preference to retrieve     * @return The preference value if it exists, or -1. Throws ClassCastException if there is a preference with this     *         name that is not a long     * @see #getLong(Context, String, long)     */    public static long getLong(Context context, String key) {        return getLong(context, key, -1);    }    /**     * get long preferences     *      * @param context     * @param key The name of the preference to retrieve     * @param defaultValue Value to return if this preference does not exist     * @return The preference value if it exists, or defValue. Throws ClassCastException if there is a preference with     *         this name that is not a long     */    public static long getLong(Context context, String key, long defaultValue) {        SharedPreferences settings = context.getSharedPreferences(PREFERENCE_NAME, Context.MODE_PRIVATE);        return settings.getLong(key, defaultValue);    }    /**     * put float preferences     *      * @param context     * @param key The name of the preference to modify     * @param value The new value for the preference     * @return True if the new values were successfully written to persistent storage.     */    public static boolean putFloat(Context context, String key, float value) {        SharedPreferences settings = context.getSharedPreferences(PREFERENCE_NAME, Context.MODE_PRIVATE);        SharedPreferences.Editor editor = settings.edit();        editor.putFloat(key, value);        return editor.commit();    }    /**     * get float preferences     *      * @param context     * @param key The name of the preference to retrieve     * @return The preference value if it exists, or -1. Throws ClassCastException if there is a preference with this     *         name that is not a float     * @see #getFloat(Context, String, float)     */    public static float getFloat(Context context, String key) {        return getFloat(context, key, -1);    }    /**     * get float preferences     *      * @param context     * @param key The name of the preference to retrieve     * @param defaultValue Value to return if this preference does not exist     * @return The preference value if it exists, or defValue. Throws ClassCastException if there is a preference with     *         this name that is not a float     */    public static float getFloat(Context context, String key, float defaultValue) {        SharedPreferences settings = context.getSharedPreferences(PREFERENCE_NAME, Context.MODE_PRIVATE);        return settings.getFloat(key, defaultValue);    }    /**     * put boolean preferences     *      * @param context     * @param key The name of the preference to modify     * @param value The new value for the preference     * @return True if the new values were successfully written to persistent storage.     */    public static boolean putBoolean(Context context, String key, boolean value) {        SharedPreferences settings = context.getSharedPreferences(PREFERENCE_NAME, Context.MODE_PRIVATE);        SharedPreferences.Editor editor = settings.edit();        editor.putBoolean(key, value);        return editor.commit();    }    /**     * get boolean preferences, default is false     *      * @param context     * @param key The name of the preference to retrieve     * @return The preference value if it exists, or false. Throws ClassCastException if there is a preference with this     *         name that is not a boolean     * @see #getBoolean(Context, String, boolean)     */    public static boolean getBoolean(Context context, String key) {        return getBoolean(context, key, false);    }    /**     * get boolean preferences     *      * @param context     * @param key The name of the preference to retrieve     * @param defaultValue Value to return if this preference does not exist     * @return The preference value if it exists, or defValue. Throws ClassCastException if there is a preference with     *         this name that is not a boolean     */    public static boolean getBoolean(Context context, String key, boolean defaultValue) {        SharedPreferences settings = context.getSharedPreferences(PREFERENCE_NAME, Context.MODE_PRIVATE);        return settings.getBoolean(key, defaultValue);    }}

3.JSONUtil

/**JSONUtil.java*Created on 2014-9-29 上午9:54 by Ivan*Copyright(c)2014 Guangzhou Onion Information Technology Co., Ltd.*http://www.cniao5.com*/package cniao5.com.cniao5shop.utils;import com.google.gson.Gson;import com.google.gson.GsonBuilder;import java.lang.reflect.Type;/** * Created by Ivan on 14-9-29. * Copyright(c)2014 Guangzhou Onion Information Technology Co., Ltd. * http://www.cniao5.com */public class JSONUtil {    private static Gson gson = new GsonBuilder().setDateFormat("yyyy-MM-dd HH:mm:ss").create();    public static  Gson getGson(){        return  gson;    }    public static <T> T fromJson(String json,Class<T> clz){        return  gson.fromJson(json,clz);    }    public static <T> T fromJson(String json,Type type){        return  gson.fromJson(json,type);    }    public static String toJSON(Object object){       return gson.toJson(object);    }}

4.数据存储器  CartProvider

package cniao5.com.cniao5shop.utils;import android.content.Context;import android.util.SparseArray;import com.google.gson.reflect.TypeToken;import java.util.ArrayList;import java.util.List;import cniao5.com.cniao5shop.bean.ShoppingCart;/** * Created by <a href="http://www.cniao5.com">菜鸟窝</a> * 一个专业的Android开发在线教育平台 */public class CartProvider {    public static final String CART_JSON="cart_json";//相当于HasMap    private SparseArray<ShoppingCart> datas =null;    private  Context mContext;    public CartProvider(Context context){        mContext = context;       datas = new SparseArray<>(10);        listToSparse();    }    //添加数据    public void put(ShoppingCart cart){       ShoppingCart temp =  datas.get(cart.getId().intValue());        //判断该商品是否已经存在        if(temp !=null){            temp.setCount(temp.getCount()+1);        }        else{            temp = cart;            temp.setCount(1);        }        datas.put(cart.getId().intValue(),temp);        commit();    }    //更新数据    public void update(ShoppingCart cart){        datas.put(cart.getId().intValue(),cart);        commit();    }//删除数据    public void delete(ShoppingCart cart){        datas.delete(cart.getId().intValue());        commit();    }//获取所有数据    public List<ShoppingCart> getAll(){        return  getDataFromLocal();    }//保存数据到本地    public void commit(){        List<ShoppingCart> carts = sparseToList();        PreferencesUtils.putString(mContext,CART_JSON,JSONUtil.toJSON(carts));    }    private List<ShoppingCart> sparseToList(){        int size = datas.size();        List<ShoppingCart> list = new ArrayList<>(size);        for (int i=0;i<size;i++){            list.add(datas.valueAt(i));        }        return list;    }    //将本地数据存放在SparseArray    private void listToSparse(){        List<ShoppingCart> carts =  getDataFromLocal();        if(carts!=null && carts.size()>0){            for (ShoppingCart cart:                    carts) {                datas.put(cart.getId().intValue(),cart);            }        }    }    //从本地获取数据转化成对象    public  List<ShoppingCart> getDataFromLocal(){        String json = PreferencesUtils.getString(mContext,CART_JSON);        List<ShoppingCart> carts =null;        if(json !=null ){            carts = JSONUtil.fromJson(json,new TypeToken<List<ShoppingCart>>(){}.getType());        }        return  carts;    }}

(1)SparseArray 代替 HasMap 

2.显示购物车商品

1.布局

<?xml version="1.0" encoding="utf-8"?><RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"    android:orientation="vertical" android:layout_width="match_parent"    android:layout_height="match_parent">    <android.support.v7.widget.RecyclerView        android:id="@+id/recycler_view"        android:layout_width="match_parent"        android:layout_height="match_parent"        android:layout_marginBottom="50dp">    </android.support.v7.widget.RecyclerView>    <RelativeLayout        android:layout_width="match_parent"        android:layout_height="wrap_content"        android:layout_alignParentBottom="true"        android:paddingTop="10dp"        android:paddingBottom="10dp"        android:paddingLeft="5dp"        android:paddingRight="5dp"        android:background="#802f4f4f"        android:gravity="center_vertical"        >        <CheckBox            android:id="@+id/checkbox_all"            android:layout_width="wrap_content"            android:layout_height="wrap_content"            android:layout_alignParentLeft="true"            android:layout_centerVertical="true"            android:checked="true"            android:text="全选"            style="@style/customCheckbox"/>        <TextView            android:id="@+id/txt_total"            android:layout_width="wrap_content"            android:layout_height="wrap_content"            android:layout_toRightOf="@+id/checkbox_all"           android:layout_marginLeft="40dp"            android:layout_centerVertical="true"            android:textSize="30dp"            android:text="合计"/>        <Button            android:id="@+id/btn_order"            android:layout_width="wrap_content"            android:layout_height="wrap_content"            android:layout_alignParentRight="true"            android:layout_centerVertical="true"            android:minHeight="60dp"            android:minWidth="120dp"            android:text="去结算"            style="@style/bigRedButton"/>        <Button            android:id="@+id/btn_del"            android:layout_width="wrap_content"            android:layout_height="wrap_content"            android:layout_alignParentRight="true"            android:layout_centerVertical="true"            android:visibility="gone"            android:minHeight="60dp"            android:minWidth="120dp"            android:text="删除"            style="@style/bigRedButton"/>    </RelativeLayout></RelativeLayout>

3.购物车商品选择和总价统计

4.购物车编辑实现

1.CartAdapter

package cniao5.com.cniao5shop.adapter;import android.content.Context;import android.net.Uri;import android.text.Html;import android.view.View;import android.widget.CheckBox;import android.widget.TextView;import com.facebook.drawee.view.SimpleDraweeView;import java.util.Iterator;import java.util.List;import cniao5.com.cniao5shop.R;import cniao5.com.cniao5shop.bean.ShoppingCart;import cniao5.com.cniao5shop.utils.CartProvider;import cniao5.com.cniao5shop.widget.NumberAddSubView;/** *购物车Adapter */public class CartAdapter extends SimpleAdapter<ShoppingCart> implements BaseAdapter.OnItemClickListener {    public static final String TAG="CartAdapter";    private CheckBox checkBox;    private TextView textView;    private CartProvider cartProvider;    public CartAdapter(Context context, List<ShoppingCart> datas, final CheckBox checkBox,TextView tv) {        super(context, R.layout.template_cart, datas);        setCheckBox(checkBox);        setTextView(tv);        cartProvider = new CartProvider(context);        setOnItemClickListener(this);        showTotalPrice();    }    @Override    protected void convert(BaseViewHolder viewHoder, final ShoppingCart item) {        viewHoder.getTextView(R.id.text_title).setText(item.getName());        viewHoder.getTextView(R.id.text_price).setText("￥"+item.getPrice());        SimpleDraweeView draweeView = (SimpleDraweeView) viewHoder.getView(R.id.drawee_view);        draweeView.setImageURI(Uri.parse(item.getImgUrl()));        CheckBox checkBox = (CheckBox) viewHoder.getView(R.id.checkbox);        checkBox.setChecked(item.isChecked());        NumberAddSubView numberAddSubView = (NumberAddSubView) viewHoder.getView(R.id.num_control);        numberAddSubView.setValue(item.getCount());        numberAddSubView.setOnButtonClickListener(new NumberAddSubView.OnButtonClickListener() {            @Override            public void onButtonAddClick(View view, int value) {                item.setCount(value);                cartProvider.update(item);                showTotalPrice();            }            @Override            public void onButtonSubClick(View view, int value) {                item.setCount(value);                cartProvider.update(item);                showTotalPrice();            }        });    }    private  float getTotalPrice(){        float sum=0;        if(!isNull())            return sum;        for (ShoppingCart cart:                datas) {            if(cart.isChecked())                sum += cart.getCount()*cart.getPrice();        }        return sum;    }    //获取总价    public void showTotalPrice(){        float total = getTotalPrice();        textView.setText(Html.fromHtml("合计 ￥<span style='color:#eb4f38'>" + total + "</span>"), TextView.BufferType.SPANNABLE);    }    private boolean isNull(){        return (datas !=null && datas.size()>0);    }    @Override    public void onItemClick(View view, int position) {       ShoppingCart cart =  getItem(position);        cart.setIsChecked(!cart.isChecked());        notifyItemChanged(position);        checkListen();        showTotalPrice();    }    private void checkListen() {        int count = 0;        int checkNum = 0;        if (datas != null) {            count = datas.size();            for (ShoppingCart cart : datas) {                if (!cart.isChecked()) {                    checkBox.setChecked(false);                    break;                } else {                    checkNum = checkNum + 1;                }            }            if (count == checkNum) {                checkBox.setChecked(true);            }        }    }    public void checkAll_None(boolean isChecked){        if(!isNull())            return ;        int i=0;        for (ShoppingCart cart :datas){            cart.setIsChecked(isChecked);            notifyItemChanged(i);            i++;        }    }    public void delCart(){        if(!isNull())            return ;//        for (ShoppingCart cart : datas){////            if(cart.isChecked()){//                int position = datas.indexOf(cart);//                cartProvider.delete(cart);//                datas.remove(cart);//                notifyItemRemoved(position);//            }//        }        for(Iterator iterator = datas.iterator();iterator.hasNext();){            ShoppingCart cart = (ShoppingCart) iterator.next();            if(cart.isChecked()){                int position = datas.indexOf(cart);                cartProvider.delete(cart);                iterator.remove();                notifyItemRemoved(position);            }        }    }    public void setTextView(TextView textview){        this.textView = textview;    }    public void setCheckBox(CheckBox ck){        this.checkBox = ck;        checkBox.setOnClickListener(new View.OnClickListener() {            @Override            public void onClick(View v) {                checkAll_None(checkBox.isChecked());                showTotalPrice();            }        });    }}

2.CartFragment

package cniao5.com.cniao5shop.fragment;import android.content.Context;import android.os.Bundle;import android.support.v4.app.Fragment;import android.support.v7.widget.LinearLayoutManager;import android.support.v7.widget.RecyclerView;import android.view.LayoutInflater;import android.view.View;import android.view.ViewGroup;import android.widget.Button;import android.widget.CheckBox;import android.widget.TextView;import com.lidroid.xutils.ViewUtils;import com.lidroid.xutils.view.annotation.ViewInject;import com.lidroid.xutils.view.annotation.event.OnClick;import java.util.List;import cniao5.com.cniao5shop.MainActivity;import cniao5.com.cniao5shop.R;import cniao5.com.cniao5shop.adapter.CartAdapter;import cniao5.com.cniao5shop.adapter.decoration.DividerItemDecoration;import cniao5.com.cniao5shop.bean.ShoppingCart;import cniao5.com.cniao5shop.utils.CartProvider;import cniao5.com.cniao5shop.widget.CnToolbar;/** * Created by Ivan on 15/9/22. */public class CartFragment extends Fragment implements View.OnClickListener{    public static final int ACTION_EDIT=1; //编辑状态    public static final int ACTION_CAMPLATE=2;//完成状态    @ViewInject(R.id.recycler_view)    private RecyclerView mRecyclerView;    @ViewInject(R.id.checkbox_all)    private CheckBox mCheckBox;    @ViewInject(R.id.txt_total)    private TextView mTextTotal;    @ViewInject(R.id.btn_order)    private Button mBtnOrder;    @ViewInject(R.id.btn_del)    private Button mBtnDel;    private CnToolbar mToolbar;    private CartAdapter mAdapter;    private CartProvider cartProvider;//改写后的TabFragment只会首次执行该方法    public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {        View view =   inflater.inflate(R.layout.fragment_cart,container,false);        ViewUtils.inject(this,view);        cartProvider = new CartProvider(getContext());        showData();        return  view;    }    @OnClick(R.id.btn_del)    public void delCart(View view){        mAdapter.delCart();    }    //显示数据    private void showData(){        List<ShoppingCart> carts = cartProvider.getAll();        mAdapter = new CartAdapter(getContext(),carts,mCheckBox,mTextTotal);        mRecyclerView.setAdapter(mAdapter);        mRecyclerView.setLayoutManager(new LinearLayoutManager(getContext()));        mRecyclerView.addItemDecoration(new DividerItemDecoration(getContext(),DividerItemDecoration.VERTICAL_LIST));    }    public void refData(){        mAdapter.clear();        List<ShoppingCart> carts = cartProvider.getAll();        mAdapter.addData(carts);        mAdapter.showTotalPrice();    }//在Fragment中获取Activity方法    @Override    public void onAttach(Context context) {        super.onAttach(context);        if(context instanceof MainActivity){            MainActivity activity = (MainActivity) context;            mToolbar = (CnToolbar) activity.findViewById(R.id.toolbar);            changeToolbar();        }    }//改变ToolBar    public void changeToolbar(){        mToolbar.hideSearchView();        mToolbar.showTitleView();        mToolbar.setTitle(R.string.cart);        mToolbar.getRightButton().setVisibility(View.VISIBLE);        mToolbar.setRightButtonText("编辑");        mToolbar.getRightButton().setOnClickListener(this);        mToolbar.getRightButton().setTag(ACTION_EDIT);    }    private void showDelControl(){        mToolbar.getRightButton().setText("完成");        mTextTotal.setVisibility(View.GONE);        mBtnOrder.setVisibility(View.GONE);        mBtnDel.setVisibility(View.VISIBLE);        mToolbar.getRightButton().setTag(ACTION_CAMPLATE);        mAdapter.checkAll_None(false);        mCheckBox.setChecked(false);    }    private void  hideDelControl(){        mTextTotal.setVisibility(View.VISIBLE);        mBtnOrder.setVisibility(View.VISIBLE);        mBtnDel.setVisibility(View.GONE);        mToolbar.setRightButtonText("编辑");        mToolbar.getRightButton().setTag(ACTION_EDIT);        mAdapter.checkAll_None(true);        mAdapter.showTotalPrice();        mCheckBox.setChecked(true);    }    @Override    public void onClick(View v) {        int action = (int) v.getTag();        if(ACTION_EDIT == action){            showDelControl();        }        else if(ACTION_CAMPLATE == action){            hideDelControl();        }    }}