Android listview点赞问题分析

最近这段时间一直在看android，利用listview去实现点赞功能

基本思路：

进入界面–》获取数据–》
在listview中显示–》
通过map集合（position,boolean）保存每一行是否被点击–》
利用实体类去保存相应的对象–》
get/set方法进行相应值得改变–》
点击一次，相应的数量加1

只实现了点赞功能，踩和赞基本类似。

具体实现如下：

继承自baseadapter

package com.gz.test_listview;

import android.content.context;
import android.content.dialoginterface;
import android.content.intent;
import android.os.handler;
import android.os.message;
import android.util.log;
import android.view.layoutinflater;
import android.view.view;
import android.view.viewgroup;
import android.widget.adapterview;
import android.widget.baseadapter;
import android.widget.button;
import android.widget.imageview;
import android.widget.listview;
import android.widget.textview;
import android.widget.toast;

import java.util.arraylist;
import java.util.hashmap;
import java.util.list;
import java.util.map;

/**
 * created by gz on 2016/11/9.
 */
public class mainactivityadapter extends baseadapter{
//用来获取界面上的元素
 private viewholder holder;
 private context context;
 //这里的bean是个测试用的内部类，将点赞数和踩得数存起来，可以定义一个类，
 //直接获取数据就好，需要改进下
 private list<bean> praise_step_num = new arraylist<bean>();

 private layoutinflater inflater;
 //保存当前点赞数
 list<map<string,object>> listitems;
 /*
 根据position，保存点击的是哪一行数据，默认为false，点击后改为true
 */
 private map<integer, boolean> isexist = new hashmap<integer, boolean>();

 public mainactivityadapter(context context,list<map<string,object>> listitems){
 this.context = context;
 this.listitems = listitems;
 inflater = layoutinflater.from(context);
 log.i("listitem",listitems.tostring());
 init();
 }

 private void init() {
 /*
 为相应的数据赋值，所有的数据存储在listitems中
 position一一对应每一行数据
  */
 for (int i = 0;i<listitems.size();i++){
  isexist.put(i,false);
  bean b = new bean();
  integer praise = integer.parseint(listitems.get(i).get("praise").tostring());
  b.setpraise(praise);
  integer step = integer.parseint(listitems.get(i).get("step").tostring());
  b.setstep(step);
  praise_step_num.add(i,b);
  log.i("praise_step",praise_step_num.get(i).getpraise()+"");
 }

 }

 @override
 public int getcount() {
 return listitems.size() ;
 }

 @override
 public object getitem(int position) {
 return position;
 }

 @override
 public long getitemid(int position) {
 return position;
 }

 @override
 public view getview(final int position, view convertview, viewgroup parent) {
 //获取赞、踩得值
 final bean bean = praise_step_num.get(position);

 if(convertview == null){
  holder = new viewholder();
  convertview = inflater.inflate(r.layout.item_praise,null);
  holder.img_praise = (imageview) convertview.findviewbyid(r.id.tv_praises_img);
  holder.img_step = (imageview) convertview.findviewbyid(r.id.tv_step_img);
  holder.praise = (textview) convertview.findviewbyid(r.id.tv_praises);
  holder.step = (textview) convertview.findviewbyid(r.id.tv_step);
  holder.title = (textview) convertview.findviewbyid(r.id.tv_name);


  //holder.img_step.setimageresource(r.drawable.bad);



  convertview.settag(holder);
 }else{
  holder = (viewholder) convertview.gettag();
 }

 holder.praise.settext(bean.getpraise()+"");
 holder.step.settext(bean.getstep()+"");
 holder.title.settext(listitems.get(position).get("title")+"");
  /*
  每次会复用convertview,
  convertview没有被赋值，就会使用之后赋值的数据，
  比如：点击了第一行数据赞的按钮，相应的第一行点赞图片变为红色
  当向下滑动页面时，下方的也会有一项数据发生变化，复用
  在这里为每次重用赋值
  */
 if(bean.getpraise()!=0){
  holder.img_praise.setimageresource(r.drawable.good);
 }else{
  holder.img_praise.setimageresource(r.drawable.good_no);
 }
 if(bean.getstep()!=0){
  holder.img_step.setimageresource(r.drawable.bad);
 }else{
  holder.img_step.setimageresource(r.drawable.bad_no);
 }


 holder.img_praise.setonclicklistener(new imgclick(position,bean));

 return convertview;
 }

 class imgclick implements view.onclicklistener {
 private int position;
 private bean bean;

 public imgclick(int position,bean bean){
  this.position = position;
  this.bean = bean;
 }
 @override
 public void onclick(final view v) {
  log.i("position",position+"");
  if(bean.getpraise()==0){
  if(isexist.get(position) == false){
   final handler handler = new handler() {
   @override
   public void handlemessage(message msg) {
    super.handlemessage(msg);
    switch (msg.what){
    case 1:
     imageview btn = (imageview) v;
     if(v.getid() == btn.getid()) {
     isexist.put(position, true);
     bean.setpraise(bean.getpraise()+1);
     btn.setimageresource(r.drawable.good);
     animationtools.scale(btn);
     notifydatasetchanged();
     break;
     }
    case 2:
     toast.maketext(context, "失败", toast.length_long).show();
     break;
    }
   }
   };
   new thread(){
   @override
   public void run() {
    message msg = new message();
    msg.what=1;
    handler.sendmessage(msg);
   }
   }.start();
  }
  }else{
  toast.maketext(context, "已经点击过", toast.length_long).show();
  }
 }
 }

 private static class viewholder{
 public imageview img_praise;

 public imageview getimg_praise() {
  return img_praise;
 }

 public imageview getimg_step() {
  return img_step;
 }

 public textview getpraise() {
  return praise;
 }

 public textview getstep() {
  return step;
 }

 public textview gettitle() {
  return title;
 }

 private imageview img_step;
 public textview praise;
 private textview step;
 private textview title;


 }

 class bean{
 public int getpraise() {
  return praise;
 }

 public void setpraise(int praise) {
  this.praise = praise;
 }

 public int getstep() {
  return step;
 }

 public void setstep(int step) {
  this.step = step;
 }

 private int praise;
 private int step;

 }
}

mainactivity

进行listview值赋值，然后进行和adapter的绑定

package com.gz.test_listview;

import android.app.activity;
import android.content.intent;
import android.support.v7.app.appcompatactivity;
import android.os.bundle;
import android.view.view;
import android.widget.adapterview;
import android.widget.listview;

import java.util.arraylist;
import java.util.hashmap;
import java.util.list;
import java.util.map;
import java.util.objects;

public class mainactivity extends activity {

 private listview listview;
 private string[] title = {"商用","家用","测试","多联","空气能","商用","家用","测试","多联","空气能"};
 private string[] praise = {"3","1","0","0","0","3","1","0","0","0"};
 private string[] step = {"3","0","0","0","0","3","0","0","0","0"};

 private arraylist<map<string,object>> map = new arraylist<map<string, object>>();

 private listview listview;
 @override
 protected void oncreate(bundle savedinstancestate) {
 super.oncreate(savedinstancestate);
 setcontentview(r.layout.activity_main);
 listview = (listview) findviewbyid(r.id.listview);
 for(int i=0;i<title.length;i++){
  map<string,object> item = new hashmap<string,object>();
  item.put("title",title[i]);
  item.put("praise",praise[i]);
  item.put("step",step[i]);
  map.add(item);
 }

 mainactivityadapter adapter = new mainactivityadapter(this,map);

 listview.setadapter(adapter);
 listview.setonitemclicklistener(new adapterview.onitemclicklistener() {
  @override
  public void onitemclick(adapterview<?> parent, view view, int position, long id) {
  intent intent = new intent(mainactivity.this,detailactivity.class);
  startactivity(intent);
  }
 });

 }
}

跳转界面，测试用

package com.gz.test_listview;

import android.app.activity;
import android.os.bundle;
import android.widget.listview;

import java.util.arraylist;
import java.util.hashmap;
import java.util.map;

public class detailactivity extends activity {


 @override
 protected void oncreate(bundle savedinstancestate) {
 super.oncreate(savedinstancestate);
 setcontentview(r.layout.detail_info);
 }
}

简单的动画效果的实现

直接用就好了

package com.gz.test_listview;

import android.view.view;
import android.view.animation.animation;
import android.view.animation.scaleanimation;

public class animationtools {
 public static void scale(view v) {
 scaleanimation anim = new scaleanimation(1.0f, 1.5f, 1.0f, 1.5f,
  animation.relative_to_self, 0.5f, animation.relative_to_self,
  0.5f);
 anim.setduration(300);
 v.startanimation(anim);

 }
}

界面

<?xml version="1.0" encoding="utf-8"?>
<relativelayout
 xmlns:android="http://schemas.android.com/apk/res/android"
 xmlns:tools="http://schemas.android.com/tools"
 android:layout_width="match_parent"
 android:layout_height="match_parent"
 android:paddingleft="@dimen/activity_horizontal_margin"
 android:paddingright="@dimen/activity_horizontal_margin"
 android:paddingtop="@dimen/activity_vertical_margin"
 android:paddingbottom="@dimen/activity_vertical_margin"
 tools:context="com.gz.test_listview.mainactivity">

 <listview
 android:id="@+id/listview"
 android:layout_width="match_parent"
 android:layout_height="wrap_content">


 </listview>
</relativelayout>

listview子项

<?xml version="1.0" encoding="utf-8"?>
<linearlayout xmlns:android="http://schemas.android.com/apk/res/android"
 android:id="@+id/lyt_root"
 android:layout_width="match_parent"
 android:layout_height="match_parent"
 android:background="#ccc"
 android:orientation="vertical"
 android:descendantfocusability= "blocksdescendants"
 >
 <framelayout
 android:layout_width="fill_parent"
 android:layout_height="wrap_content" >


 <imageview
  android:id="@+id/has_exame"
  android:layout_width="wrap_content"
  android:layout_height="wrap_content"
  android:layout_gravity="top|left"
  />

 <linearlayout
  android:layout_margin="10dip"
  android:layout_width="fill_parent"
  android:layout_height="wrap_content"
  android:layout_gravity="center_vertical"
  android:background="@drawable/corners"
  android:layout_weight="1.0"
  android:orientation="vertical"
  >

  <textview
  android:id="@+id/tv_name"
  android:layout_width="match_parent"
  android:layout_height="wrap_content"
  android:textsize="14sp"
  android:text="商用多联机"
  android:textcolor="#000"
  />

  <linearlayout
  android:layout_width="fill_parent"
  android:layout_height="wrap_content"
  android:orientation="horizontal" >

  <textview
   android:id="@+id/tv_date"
   android:layout_margintop="10dip"
   android:layout_width="match_parent"
   android:layout_height="wrap_content"
   android:textsize="12sp"
   android:text="时间 2016-10-10"
   android:textcolor="#000"
   android:visibility="visible"
   />

  <textview
   android:id="@+id/tv_downloads"
   android:layout_width="wrap_content"
   android:layout_height="wrap_content"
   android:layout_gravity="center_vertical"
   android:layout_weight="1"
   android:textcolor="#000"
   android:textsize="14sp"
   android:visibility="gone" />


  </linearlayout>

  <linearlayout
  android:layout_width="match_parent"
  android:layout_height="match_parent"
  android:orientation="horizontal"
  android:gravity="center|right"
  >

  <imageview
   android:id="@+id/tv_praises_img"
   android:layout_width="30dip"
   android:layout_height="30dip"
   android:background="@drawable/good_no"
   android:layout_marginright="5dip"
   />
  <textview
   android:id="@+id/tv_praises"
   android:layout_width="50dip"
   android:layout_height="wrap_content"
   android:textcolor="#000"
   android:text="10"
   android:textsize="14dip"
   android:layout_gravity="center"
   />

  <imageview
   android:id="@+id/tv_step_img"
   android:layout_width="30dip"
   android:layout_height="30dip"
   android:background="@drawable/bad_no"
   android:layout_marginright="5dip"

   />
  <textview
   android:id="@+id/tv_step"
   android:layout_width="50dip"
   android:layout_height="wrap_content"
   android:textcolor="#000"
   android:text="10"
   android:textsize="14dip"
   android:layout_gravity="center"
   />

  </linearlayout>

 </linearlayout>


 </framelayout>

</linearlayout>

点击item后进入的界面

<?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"
 android:paddingleft="@dimen/activity_horizontal_margin"
 android:paddingright="@dimen/activity_horizontal_margin"
 android:paddingtop="@dimen/activity_vertical_margin"
 android:paddingbottom="@dimen/activity_vertical_margin"
 android:orientation="vertical"
 >

 <textview
 android:layout_width="wrap_content"
 android:layout_height="wrap_content"
 android:text="111"
 />
 <textview
 android:layout_width="wrap_content"
 android:layout_height="wrap_content"
 android:text="111"
 />
 <textview
 android:layout_width="wrap_content"
 android:layout_height="wrap_content"
 android:text="111"
 />
 <textview
 android:layout_width="wrap_content"
 android:layout_height="wrap_content"
 android:text="111"
 />
 <textview
 android:layout_width="wrap_content"
 android:layout_height="wrap_content"
 android:text="111"
 />


</linearlayout>

代码中是我对程序的理解，有的地方可能不是很明白，还得完善完善
这篇文章给了我很大帮助，动画效果就是搬过来的，哈哈，很不错，学习了。

参考文章：

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。