Android学习0825(ListView和Adapter拓展)

ViewHolder和convertview

为了防止当数据过多时,出现错误,利用一个convertview对View进行缓存,可以给下一个重新使用。
先定义一个Student类

package StudentAdapter;

import android.widget.ImageView;

/**
 * Created by Administrator on 2015/8/24.
 */
public class Student {
    private String name;
    private String age;
    private String sex;
    private String hobit;
    private int image;
    public  Student(String name,String sex,String age,String hobit,int image){
        this.name=name;
        this.age=age;
        this.sex=sex;
        this.hobit=hobit;
        this.image=image;
    }

    public int getImage() {
        return image;
    }

    public void setImage(int image) {
        this.image = image;
    }

    public String getName() {
        return name;
    }

    public String getHobit() {
        return hobit;
    }

    public String getSex() {
        return sex;
    }

    public String getAge() {
        return age;
    }

    public void setName(String name) {
        this.name = name;
    }

    public void setAge(String  age) {
        this.age = age;
    }

    public void setSex(String sex) {
        this.sex = sex;
    }

    public void setHobit(String hobit) {
        this.hobit = hobit;
    }
}

定义一个StudentAdapter的适配器,添加convertview

package StudentAdapter;

import android.util.Log;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.BaseAdapter;
import android.widget.ImageView;
import android.widget.TextView;

import com.example.administrator.myapplication.R;
import StudentAdapter.StudentAdapter.ViewHolder;
import java.util.HashMap;
import java.util.List;

/**
 * Created by Administrator on 2015/8/24.
 */
public class StudentAdapter extends BaseAdapter{
    private List mData;
    private LayoutInflater mInflater;
    private int count;
    public StudentAdapter(LayoutInflater Inflater,List data){
        //将Inflater和数据传递到
        mInflater=Inflater;
        mData=data;
    }
    @Override
    //
    public int getCount() {
        count=mData.size();
         return mData.size();
    }

    @Override
    public Object getItem(int position) {
        return null;
    }

    @Override
    public long getItemId(int position) {
        return 0;
    }

    @Override
    public View getView(int position, View convertView, ViewGroup parent) {
        Student student =mData.get(position);
//        添加了防止多条数据出错的机制
        if (convertView==null){
            convertView=mInflater.inflate(R.layout.acativity_simpleadapter,null);
        }
        ImageView imageView= (ImageView) convertView.findViewById(R.id.image);
        TextView textview_name= (TextView) convertView.findViewById(R.id.textview_name);
        TextView textview_age= (TextView) convertView.findViewById(R.id.textview_age);
        TextView textview_sex= (TextView) convertView.findViewById(R.id.textview_sex);
        TextView textview_hobit= (TextView) convertView.findViewById(R.id.textview_hobit);
        textview_name.setText(student.getName());
        textview_age.setText(student.getAge());
        textview_sex.setText(student.getSex());
        textview_hobit.setText(student.getHobit());
        imageView.setImageResource(student.getImage());
        return convertView;
    }

因为每次使用convertview时都要对findViewbyId进行一次实例,为了减少内存的占用,自定义一个viewHolder方法

package StudentAdapter;

import android.util.Log;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.BaseAdapter;
import android.widget.ImageView;
import android.widget.TextView;

import com.example.administrator.myapplication.R;
import StudentAdapter.StudentAdapter.ViewHolder;
import java.util.HashMap;
import java.util.List;

/**
 * Created by Administrator on 2015/8/24.
 */
public class StudentAdapter extends BaseAdapter{
    private List mData;
    private LayoutInflater mInflater;
    private int count;
    public StudentAdapter(LayoutInflater Inflater,List data){
        //将Inflater和数据传递到
        mInflater=Inflater;
        mData=data;
    }
    @Override
    //
    public int getCount() {
        count=mData.size();
         return mData.size();
    }

    @Override
    public Object getItem(int position) {
        return null;
    }

    @Override
    public long getItemId(int position) {
        return 0;
    }

    @Override
    public View getView(int position, View convertView, ViewGroup parent) {
        Student student =mData.get(position);
        //为了减少内存的使用
        ViewHolder vh=null;
        if (convertView==null) {
            vh=new ViewHolder();
            convertView=mInflater.inflate(R.layout.acativity_simpleadapter,null);
            vh.imageView= (ImageView) convertView.findViewById(R.id.image);
            vh.textview_name= (TextView) convertView.findViewById(R.id.textview_name);
            vh.textview_age= (TextView) convertView.findViewById(R.id.textview_age);
            vh.textview_sex= (TextView) convertView.findViewById(R.id.textview_sex);
            vh.textview_hobit= (TextView) convertView.findViewById(R.id.textview_hobit);
            convertView.setTag(vh);
            Log.d("convertView","convertView为空时加载"+count);
        }else{
            vh= (ViewHolder) convertView.getTag();
            Log.d("convertView","convertView不为空时加载"+count);
        }
        count++;
        vh.textview_name.setText(student.getName());
        vh.textview_age.setText(student.getAge());
        vh.textview_sex.setText(student.getSex());
        vh.textview_hobit.setText(student.getHobit());
        vh.imageView.setImageResource(student.getImage());
        return convertView;
    }
    class ViewHolder{
        ImageView imageView;
        TextView textview_name;
        TextView textview_age;
        TextView textview_sex;
        TextView textview_hobit;
    }
}

AdapterViewActivity类中

package com.example.administrator.myapplication;

import android.app.Activity;
import android.os.Bundle;
import android.util.Log;
import android.view.LayoutInflater;
import android.view.View;
import android.widget.ArrayAdapter;
import android.widget.Button;
import android.widget.ListView;

import java.util.ArrayList;
import java.util.List;

import StudentAdapter.Student;
import StudentAdapter.StudentAdapter;

/**
 * Created by Administrator on 2015/8/24.
 */
public class AdpaterViewActivity extends Activity {
    private ListView listView_name;
    private List mDataStudent;
    private String []array={"张三","李四","王五","赵六"};
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_adapterview);
        listView_name= (ListView) findViewById(R.id.listview_adapterview);
        LayoutInflater inflater=getLayoutInflater();
        setData();
        StudentAdapter studentAdapter=new StudentAdapter(inflater,mDataStudent);
        Log.d("Null point",""+listView_name+"11111");
        listView_name.setAdapter(studentAdapter);
    }
    private void setData() {
        mDataStudent=new ArrayList<>();
        Student zhangsan=new Student("张三", "男", "18", "打球",R.mipmap.jie1);
        Student lisi=new Student("李四","男","21","爱吃",R.mipmap.image_boy);
        Student wangwu=new Student("王五","女","19","爱喝",R.mipmap.jie7);
        Student zhaoliu=new Student("赵六","女","20","爱玩",R.mipmap.image_girl);
        for (int i=0;i<50;i++){
            mDataStudent.add(zhangsan);
            mDataStudent.add(lisi);
            mDataStudent.add(wangwu);
            mDataStudent.add(zhaoliu);
        }

    }
}

Android学习0825(ListView和Adapter拓展)_第1张图片

divider和dividerHeight

android:cacheColorHint=”#00000000”设置listview背景的颜色
android:divider=”@color/treegreen”设置LisView的数据间的间隔的颜色
android:dividerHeight=”2dp”设置ListView的数据间的间隔距离
activity_adapterview.xml(同时也是上面的convertView布局)

"http://schemas.android.com/apk/res/android"
    android:orientation="vertical" android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:background="@mipmap/image_bac_green">
    "@+id/listview_adapterview"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:cacheColorHint="#00000000"
        android:divider="@color/treegreen"
        android:dividerHeight="2dp">

activity_simpleadapter.xml

"http://schemas.android.com/apk/res/android"
    android:orientation="horizontal" android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:background="@drawable/adapter_bacground">

    "@+id/image"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content" />
    "wrap_content"
        android:layout_height="wrap_content"
        android:orientation="horizontal">
        "@+id/textview_name"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_gravity="center"
            />
        "wrap_content"
            android:layout_height="wrap_content"
            android:orientation="vertical"
            >
            "@+id/textview_age"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                />
            "@+id/textview_sex"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                />
        
        "@+id/textview_hobit"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_gravity="center"/>
    

adapter_bacground.xml

"1.0" encoding="utf-8"?>
"http://schemas.android.com/apk/res/android">
    "@mipmap/imagegreen"
        android:state_pressed="true"
        />
    
        
        

Android学习0825(ListView和Adapter拓展)_第2张图片

在ListView中添加控件

在activity_fruit_adapter中添加checkBox
在ListView中设置屏蔽子控件抢夺ListView的焦点,在ListView中添加

android:descendantFocusability="blocksDescendants"

在子控件本身设置焦点属性为false

android:focusable="false"

>

activity_fruit_adapter

"1.0" encoding="utf-8"?>
"http://schemas.android.com/apk/res/android"
    android:orientation="horizontal" android:layout_width="match_parent"
    android:layout_height="match_parent">
    "@+id/checkbox_fruit"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:focusable="false"
        android:text="选择的水果是"/>
    "@+id/image_fruit"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:src="@mipmap/apple"/>
    "@+id/text_fruit"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="苹果"/>

activity_fruit.xml

"1.0" encoding="utf-8"?>
"http://schemas.android.com/apk/res/android"
    android:orientation="vertical" android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:background="@mipmap/image_bac_green">
    "@+id/listview_fruit"
        android:layout_width="match_parent"
        android:layout_height="match_parent">

Fruit.java

package StudentAdapter;

/**
 * Created by Administrator on 2015/8/25.
 */
public class Fruit {
    private int img;
    private String fruit_name;
    private boolean isCheck;
    public Fruit( String fruit_name,int img) {
        this.img = img;
        this.fruit_name = fruit_name;
    }

    public boolean isCheck() {
        return isCheck;
    }

    public void setIsCheck(boolean isCheck) {
        this.isCheck = isCheck;
    }

    public int getImg() {
        return img;
    }

    public void setImg(int img) {
        this.img = img;
    }

    public String getFruit_name() {
        return fruit_name;
    }

    public void setFruit_name(String fruit_name) {
        this.fruit_name = fruit_name;
    }
}

添加一个Frutiadapter适配器FruitAdapter.java

package StudentAdapter;

import android.util.Log;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.BaseAdapter;
import android.widget.CheckBox;
import android.widget.CompoundButton;
import android.widget.ImageView;
import android.widget.TextView;

import com.example.administrator.myapplication.R;

import java.util.List;

/**
 * Created by Administrator on 2015/8/25.
 */
public class FruitAdapter extends BaseAdapter{
    private List mData;
    private LayoutInflater mInflater;
    private int count;
    private boolean []mMangerAllCheckBox;
    public FruitAdapter( LayoutInflater mInflater,List mData) {
        this.mData = mData;
        this.mInflater = mInflater;
        mMangerAllCheckBox=new boolean[mData.size()];
    }
    public void checkedAll(){
        for (int i=0;itrue;
        }
        notifyDataSetChanged();
    }
    public void contraryChecked(){
        for (int i=0;ipublic void itemSelect(int position){
        mMangerAllCheckBox[position]=!mMangerAllCheckBox[position];
        notifyDataSetChanged();
    }
    @Override
    public int getCount() {
        return mData.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) {
       Fruit fruit =mData.get(position);
        ViewHolder vh=null;
        if (convertView==null) {
            vh=new ViewHolder();
            convertView=mInflater.inflate(R.layout.activity_fruit_adapter,null);
            vh.checkBox_fruit= (CheckBox) convertView.findViewById(R.id.checkbox_fruit);
            vh.imageView= (ImageView) convertView.findViewById(R.id.image_fruit);
            vh.textview_name= (TextView) convertView.findViewById(R.id.text_fruit);
            convertView.setTag(vh);
        }else{
            vh= (ViewHolder) convertView.getTag();
        }
        count++;
        vh.textview_name.setText(fruit.getFruit_name());
        vh.imageView.setImageResource(fruit.getImg());
        vh.checkBox_fruit.setOnCheckedChangeListener(new CompoundButton.OnCheckedChangeListener() {
            @Override
            public void onCheckedChanged(CompoundButton buttonView, boolean isChecked) {
                Log.d("myfruit","选择框的变化为:"+isChecked);
                mData.get(position).setIsCheck(isChecked);
                notifyDataSetChanged();
            }
        });
        vh.checkBox_fruit.setChecked(mMangerAllCheckBox[position]);
        return convertView;
    }
    class ViewHolder{
        ImageView imageView;
        TextView textview_name;
        CheckBox checkBox_fruit;
    }
}

FruitAdapterAvitvity.java

package com.example.administrator.myapplication;

import android.app.Activity;
import android.os.Bundle;
import android.util.Log;
import android.view.LayoutInflater;
import android.view.View;
import android.widget.AdapterView;
import android.widget.Button;
import android.widget.ListView;

import java.util.ArrayList;
import java.util.List;

import StudentAdapter.Fruit;
import StudentAdapter.FruitAdapter;



/**
 * Created by Administrator on 2015/8/25.
 */
public class FruitAdapterActivity extends Activity{
    private ListView listView_name;
    private List mDataFruit;
    private FruitAdapter fruitAdapter;
    private Button button_checkAll;
    private Button button_contraryCheck;
    private View headerView;
    private View bottomView;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_fruit);
        listView_name= (ListView) findViewById(R.id.listview_fruit);
        LayoutInflater inflater=getLayoutInflater();
        setData();
//        final FruitAdapter fruitAdapter=new FruitAdapter(inflater,mDataFruit);


        headerView=inflater.inflate(R.layout.activity_checkall,null);

        button_checkAll= (Button) headerView.findViewById(R.id.button_checkAll);
        button_checkAll.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                fruitAdapter.checkedAll();
            }
        });
        listView_name.addHeaderView(headerView);
        bottomView=inflater.inflate(R.layout.activity_contrarycheck,null);
        button_contraryCheck= (Button) bottomView.findViewById(R.id.button_contraryCheck);
        button_contraryCheck.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                fruitAdapter.contraryChecked();
            }
        });
        listView_name.addFooterView(bottomView);

        fruitAdapter=new FruitAdapter(inflater,mDataFruit);
        listView_name.setAdapter(fruitAdapter);
        listView_name.setOnItemClickListener(new AdapterView.OnItemClickListener() {
            @Override
            public void onItemClick(AdapterView parent, View view, int position, long id) {
                Log.d("Myfruit","水果名称"+mDataFruit.get(position-1).getFruit_name());
                fruitAdapter.itemSelect(position-1);
            }
        });
    }
    private void setData() {
        mDataFruit = new ArrayList<>();
        for (int i = 0; i < 5; i++) {
            Fruit apple = new Fruit("苹果", R.mipmap.apple);
            Fruit pineapple = new Fruit("菠萝", R.mipmap.pineapple);
            Fruit strawberry = new Fruit("草莓", R.mipmap.strawberry);
            Fruit watermelon = new Fruit("西瓜", R.mipmap.fruit_ninja);
            mDataFruit.add(apple);
            mDataFruit.add(pineapple);
            mDataFruit.add(strawberry);
            mDataFruit.add(watermelon);
        }
    }
}

添加activity_checkall.xml和activity_contrarycheck.xml

"1.0" encoding="utf-8"?>
"http://schemas.android.com/apk/res/android"
    android:orientation="vertical" android:layout_width="match_parent"
    android:layout_height="match_parent">
"1.0" encoding="utf-8"?>
"http://schemas.android.com/apk/res/android"
    android:orientation="vertical" android:layout_width="match_parent"
    android:layout_height="match_parent">

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