我的android學習經曆34

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用類對象作為ArrayAdapter綁定的基礎資料型別 (Elementary Data Type)（和SimpleAdater效果類似）

一般ArrayAdapter綁定的基礎資料型別 (Elementary Data Type)是String，接下來介紹一下類對象作為基礎資料型別 (Elementary Data Type)；

首先，建立一個類News，這個類作為基本的資料類型

package com.example.news;import android.R.integer;import android.widget.ImageView;public class News {       private String title;       private String content;       private int imageId;              News(String title,String content,int imageId){           this.title=title;           this.content=content;           this.imageId=imageId;       }              public String  getTitle() {        return title;    }       public String  getContent() {           return content;       }       public int  getimageId() {              return imageId;          }      public void setTitle(String title){          this.title=title;      }      public void setContent(String content){          this.content=content;      }}

接下來先把listView的item的布局確定下來，有一個Textview和ImageView；

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"    android:layout_width="match_parent"    android:layout_height="match_parent"    android:orientation="vertical" >    <TextView         android:id="@+id/news_title"        android:layout_width="wrap_content"        android:layout_height="wrap_content"/>    <ImageView         android:id="@+id/news_image"        android:layout_width="wrap_content"        android:layout_height="wrap_content"/></LinearLayout>

 

然後自訂一個適配器NewsAdapter，繼承ArrayAdapter，並且實現其中的兩個方法，resourceId也就是上面的listView的item的布局的id；

package com.example.news;import java.util.List;import android.content.Context;import android.view.LayoutInflater;import android.view.View;import android.view.ViewGroup;import android.widget.ArrayAdapter;import android.widget.ImageView;import android.widget.TextView;public class NewsAdapter extends ArrayAdapter<News>{        private int resourceId;        public NewsAdapter(Context context, int resource, List<News> objects) {        super(context, resource, objects);        // TODO Auto-generated constructor stub        resourceId=resource;    }    @Override    public View getView(int position, View convertView, ViewGroup parent) {        // TODO Auto-generated method stub         News news=getItem(position);        View view ;        if(convertView==null){            view=LayoutInflater.from(getContext()).inflate(resourceId, null);        }else {            view=convertView;        }        TextView news_title=(TextView) view.findViewById(R.id.news_title);        ImageView news_image=(ImageView) view.findViewById(R.id.news_image);                news_title.setText(news.getTitle());        news_image.setImageResource(news.getimageId());        return view;    }}

然後在主布局中添加一個listview控制項，這個簡單，大家肯定都會

<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"    tools:context="${relativePackage}.${activityClass}" >    <ListView         android:id="@+id/list_title"        android:layout_width="wrap_content"        android:layout_height="match_parent"></ListView></RelativeLayout>

然後重寫主activity

import java.util.ArrayList;import java.util.List;import android.app.Activity;import android.os.Bundle;import android.view.Menu;import android.view.MenuItem;import android.widget.ListView;public class MainActivity extends Activity {        private ListView list_title;    private List<News> list= new ArrayList<News>();        private NewsAdapter adapter;    @Override    protected void onCreate(Bundle savedInstanceState) {        super.onCreate(savedInstanceState);        setContentView(R.layout.activity_main);        list_title=(ListView) findViewById(R.id.list_title);        initList();            adapter=new NewsAdapter(this, R.layout.news_item,list);        list_title.setAdapter(adapter);    }    private void initList() {                News news1=new News("標題1", "1", R.drawable.ic_launcher);        list.add(news1);        News news2=new News("標題2", "2", R.drawable.ic_launcher);        list.add(news2);        News news3=new News("標題3", "3", R.drawable.ic_launcher);        list.add(news3);        News news4=new News("標題4", "4", R.drawable.ic_launcher);        list.add(news4);    }    }

介面效果

 

不懂得可以留言

 

我的android學習經曆34