当前位置： 移动技术网 > IT编程>移动开发>Android > Android实现商品展示效果

Android实现商品展示效果

2019年07月24日  | 移动技术网IT编程  | 我要评论

一、 创建手机界面布局

创建一个activity_main.xml文件代码如下：

<?xml version="1.0" encoding="utf-8"?>
<linearlayout xmlns:android="http://schemas.android.com/apk/res/android"
 xmlns:tools="http://schemas.android.com/tools"
 android:id="@+id/activity_main"
 android:layout_width="match_parent"
 android:layout_height="match_parent"
 android:paddingbottom="@dimen/activity_vertical_margin"
 android:paddingleft="@dimen/activity_horizontal_margin"
 android:paddingright="@dimen/activity_horizontal_margin"
 android:paddingtop="@dimen/activity_vertical_margin"
 tools:context="com.example.bz0209.shopshowdemo.activity_main"
 android:orientation="vertical">
 <linearlayout
 android:layout_width="match_parent"
 android:layout_height="wrap_content">

 <edittext
 android:id="@+id/etname"
 android:layout_width="wrap_content"
 android:layout_height="wrap_content"
 android:hint="商品名称"
 android:inputtype="text"
 android:layout_weight="1"
 />
 <edittext
 android:id="@+id/etamount"
 android:layout_width="wrap_content"
 android:layout_height="wrap_content"
 android:hint="商品金额"
 android:inputtype="number"
 android:layout_weight="1"
 />
 <imageview
 android:id="@+id/ivadd"
 android:layout_width="wrap_content"
 android:layout_height="wrap_content"
 android:onclick="addgoods"
 android:inputtype="text"
 android:src="@android:drawable/ic_input_add"
 />
 </linearlayout>
 <listview
 android:id="@+id/lvgoods"
 android:layout_width="match_parent"
 android:layout_height="match_parent">

 </listview>
</linearlayout>

效果图如下：

二、创建一个存储展示的xml文件

创建一个名为item.xml的布局文件，代码如下：

<?xml version="1.0" encoding="utf-8"?>
<linearlayout xmlns:android="http://schemas.android.com/apk/res/android"
 android:layout_width="match_parent"
 android:layout_height="match_parent">
 <textview
 android:text="1"
 android:layout_width="wrap_content"
 android:layout_height="wrap_content"
 android:id="@+id/tvid"
 android:textsize="20sp"
 android:layout_weight="2"

 />
 <textview
 android:text="商品名称"
 android:layout_width="wrap_content"
 android:layout_height="wrap_content"
 android:id="@+id/tvname"
 android:textsize="20sp"
 android:layout_weight="2"

 />
 <textview
 android:text="金额"
 android:layout_width="wrap_content"
 android:layout_height="wrap_content"
 android:id="@+id/tvamount"
 android:textsize="20sp"
 android:layout_weight="2"
 />
 <imageview
  android:id="@+id/ivup"
  android:layout_width="wrap_content"
  android:layout_height="wrap_content"
  android:src="@android:drawable/arrow_up_float"
  />
 <imageview
  android:id="@+id/ivdown"
  android:layout_width="wrap_content"
  android:layout_height="wrap_content"
  android:src="@android:drawable/arrow_down_float"
  />
 <imageview
  android:id="@+id/ivdelete"
  android:layout_width="wrap_content"
  android:layout_height="wrap_content"
  android:src="@android:drawable/arrow_down_float"
  />
</linearlayout>

三、创建数据库

在com.example.bz0209.shopshowdemo 的包下创建一个名为db的包，并在该包下定义一个dbhelper类继承自sqliteopenhelper，创建数据库代码如下：

package com.example.bz0209.shopshowdemo.db;

import android.content.context;

import android.database.sqlite.sqlitedatabase;
import android.database.sqlite.sqliteopenhelper;

/**
 * created by administrator on 2017/4/28.
 */

public class dbhelper extends sqliteopenhelper{
 public static final string create_goods="create table goods(_id integer primary key autoincrement,name varchar(20),amount integer)";
 public dbhelper(context context,int version){
 super(context,"goods.db",null,version);
 }
 @override
 public void oncreate(sqlitedatabase db) {
 db.execsql(create_goods);
 }

 @override
 public void onupgrade(sqlitedatabase db,int oldversion,int newversion) {
 }
}

四、创建goodsadapter类

为了操作数据库方便，创建一个goodsadapter类。因此需要在com.example.bz0209.shopshowdemo 的包下创建一个名为entity的包，然后在com.example.bz0209.shopshowdemo.entityd的包下定义一个goodsadapter类，代码如下：

package com.example.bz0209.shopshowdemo;

import android.content.context;
import android.support.annotation.nonnull;
import android.view.layoutinflater;
import android.view.view;
import android.view.viewgroup;
import android.widget.arrayadapter;
import android.widget.imageview;
import android.widget.textview;

import com.example.bz0209.shopshowdemo.entity.goods;

import java.util.list;

/**
 * created by administrator on 2017/4/27.
 */

public class goodsadapter extends arrayadapter<goods>{
 private int resounceid;

 public goodsadapter(context context, int resource, list<goods> objects) {
 super(context, resource, objects);
 resounceid=resource;
 }

 @nonnull
 @override
 public view getview(int position, view convertview, viewgroup parent) {
 goods goods=getitem(position);
 view view=null;
 viewholder viewholder;
 if (convertview==null){
  view = layoutinflater.from(getcontext()).inflate(resounceid,null);
  viewholder =new viewholder();
  viewholder.tvid=(textview) view.findviewbyid(r.id.tvid);
  viewholder.tvname=(textview) view.findviewbyid(r.id.tvname);
  viewholder.tvamount=(textview) view.findviewbyid(r.id.etamount);
  viewholder.ivup=(imageview) view.findviewbyid(r.id.ivup);
  viewholder.ivdown=(imageview) view.findviewbyid(r.id.ivdown);
  viewholder.ivdelete=(imageview) view.findviewbyid(r.id.ivdelete);
  view.settag(viewholder);
 }else {
  view=convertview;
  viewholder=(viewholder) view.gettag();
 }
 viewholder.tvid.settext(goods.getid()+"");
 viewholder.tvname.settext(goods.getname());
 viewholder.tvamount.settext(goods.getamount()+"");

 return view;
 }
 class viewholder{
 textview tvid;
 textview tvname;
 textview tvamount;
 imageview ivup;
 imageview ivdown;
 imageview ivdelete;
 }
}

五、创建数据操作逻辑类

在com.example.bz0209.shopshowdemo 的包下创建一个名为dao的包，并创建一个名为goodsdao的类，用于操作数据。代码如下：

public class goodsdao {
 private dbhelper dbhelper;


 public goodsdao(context context){
 dbhelper=new dbhelper(context,1);
 }

 public void add(goods goods){
 sqlitedatabase sqlitedatabase=dbhelper.getwritabledatabase();
 contentvalues values=new contentvalues();
 values.put("name",goods.getname());
 values.put("amount",goods.getamount());
 sqlitedatabase.insert("goods",null,values);
 sqlitedatabase.close();


 }
 public int delete(long id){
 sqlitedatabase sqlitedatabase=dbhelper.getwritabledatabase();
 int count=sqlitedatabase.delete("goods","id=?",new string[]{id+""});
 sqlitedatabase.close();
 return count;

 }
 public int update(goods goods){
 sqlitedatabase sqlitedatabase=dbhelper.getwritabledatabase();
 contentvalues values=new contentvalues();
 values.put("name",goods.getname());
 values.put("amount",goods.getamount());
 int count=sqlitedatabase.update("goods",values,"id=?",new string[]{goods.getid()+""});
 sqlitedatabase.close();
 return count;
 }
 public list<goods> queryall(){
 list<goods>goodslist=new arraylist<>();
 sqlitedatabase sqlitedatabase=dbhelper.getreadabledatabase();
 cursor cursor=sqlitedatabase.query("goods",null,null,null,null,null,"amount desc");
 while (cursor.movetonext()){
  long id=cursor.getlong(cursor.getcolumnindex("_id"));
  string name=cursor.getstring(cursor.getcolumnindex("name"));
  int amount=cursor.getint(cursor.getcolumnindex("amount"));
  goods goods=new goods(name,amount);
  goodslist.add(goods);
 }
 cursor.close();
 sqlitedatabase.close();
 return goodslist;
 }

}

六、编写界面交互代码

数据库操作完成后，需要界面与数据库进行交互，用于实现将数据库中的数据以listview的形式展现在界面上具体代码如下：

package com.example.bz0209.shopshowdemo;
import android.support.v7.app.appcompatactivity;
import android.os.bundle;
import android.view.view;
import android.widget.edittext;
import android.widget.listview;
import com.example.bz0209.shopshowdemo.dao.goodsdao;
import com.example.bz0209.shopshowdemo.entity.goods;
import java.util.list;
public class activity_main extends appcompatactivity {
 private edittext etname;
 private edittext etamount;
 private listview lvgoods;
 private goodsadapter goodsadapter;
 private goodsdao goodsdao;
 private list<goods>goodslist;
 @override
 protected void oncreate(bundle savedinstancestate) {
 super.oncreate(savedinstancestate);
 setcontentview(r.layout.activity_main);
 etname=(edittext)findviewbyid(r.id.etname);
 etamount=(edittext)findviewbyid(r.id.etamount);
 lvgoods=(listview)findviewbyid(r.id.lvgoods);
 goodsdao=new goodsdao(this);
 goodslist=goodsdao.queryall();
 goodsadapter=new goodsadapter(this,r.layout.item,goodslist);
 lvgoods.setadapter(goodsadapter);
 }
 public void addgoods(view view){
 string name=etname.gettext().tostring();
 string amount=etamount.gettext().tostring();
 goods goods=new goods(name,amount.equals("")?0:integer.parseint(amount));
 goodsdao.add(goods);

 }
}

七、完成后的结果展示

（1）创建起数据库的图为：

（2）最后的运行结果图：

以上就是本文的全部内容，希望对大家的学习有所帮助，也希望大家多多支持移动技术网。

您可能感兴趣的文章:

如对本文有疑问， 点击进行留言回复！！

相关文章:

验证码：
最近更新的文章
大家感兴趣的文章
移动技术网