GridView学习笔记

自我对GridView的认知：

GridView就好像是我们在查看图片的时候会显示多少行多少列的图片，可以对比记忆Java中的的GridLayout。我暂且称其为网格控件。

mygridview项目列表如下图：下面会详细附上各部分的代码。依然按照先layout后Java最后manifests的顺序。

项目测试结果如下图：

activity_main.xml中的代码：

说明，使用自定义的相对布局，里面加上一个GridView控件，设置列数为3列

<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: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=".MainActivity">

    <GridView
        android:id="@+id/gridView_id"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:numColumns="3"
        ></GridView>

</RelativeLayout>

gridviewtest.xml代码

说明：最外层采用线性布局，有一个10dp的padding(填充),里面也采用线性布局添加一个ImageView、和TextView

<?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:padding="10dp"
    android:orientation="vertical" >

    <LinearLayout

        android:id="@+id/linearlayout_id"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:orientation="vertical"
        >

         <ImageView
        android:id="@+id/image_grideview"
        android:layout_width="80dp"
        android:layout_height="80dp"

        />
    <TextView 
        android:id="@+id/text_fruitname"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="水果名字"
        android:layout_gravity="center_horizontal"

        />

    </LinearLayout>



</LinearLayout>

MyGridViewAdapter.java

:说明：MyGridViewAdapter这个类继承自BaseAdapter,实现了BaseAdapter类中的四个抽象的方法，但最重要的是getView这个方法。

package com.example.administrator.mygridview.adapter;

import java.util.List;



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.mygridview.R;
import com.example.administrator.mygridview.model.Fruit;

public class MyGridViewAdapter extends BaseAdapter{

    private List<Fruit> mFruit;
    private LayoutInflater inflater;


    public MyGridViewAdapter(List<Fruit> mFruit,LayoutInflater inflater)
    {
            this.mFruit=mFruit;
            this.inflater=inflater;
    }


    @Override
    public int getCount() {
        // TODO Auto-generated method stub
        return mFruit.size();
    }

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

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

    @Override
    public View getView(int position, View convertView, ViewGroup parent) {

        ViewHolder viewHolder=null;
        if(convertView==null)
        {
            convertView=inflater.inflate(R.layout.grideviewtest, null);
            viewHolder=new ViewHolder();
            viewHolder.imageView = (ImageView) convertView.findViewById(R.id.image_grideview);
            viewHolder.textView=(TextView) convertView.findViewById(R.id.text_fruitname);

            convertView.setTag(viewHolder);
        }else
        {
            viewHolder=(ViewHolder)convertView.getTag();
        }

        Fruit fruit=mFruit.get(position);
        viewHolder.imageView.setImageResource(fruit.getImg());
        viewHolder.textView.setText(fruit.getName());

        return convertView;
    }

        class   ViewHolder
        {
            ImageView imageView;
            TextView textView;
        }

}

:Fruit.java代码

package com.example.administrator.mygridview.model;

public class Fruit {
    private String name;
    private int img;

    public Fruit(String name,int img)
    {
        this.name = name;
        this.img = img;
    }

    public String getName() {
        return name;
    }
    public void setName(String name) {
        this.name = name;
    }
    public int getImg() {
        return img;
    }
    public void setImg(int img) {
        this.img = img;
    }




}

MainActivity.java代码

说明：通过ininFruit();方法来得到数据，通过inflater=getLayoutInflater();来得到inflater,通过MyGridViewAdapter的构造器得到一个adapter。通过griaView.setAdapter(adapter)来加载这个适配器.

package com.example.administrator.mygridview;

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

import android.os.Bundle;
import android.app.Activity;
import android.view.LayoutInflater;
import android.view.Menu;
import android.widget.GridView;

import com.example.administrator.mygridview.adapter.MyGridViewAdapter;
import com.example.administrator.mygridview.model.Fruit;

public class MainActivity extends Activity {

    private GridView griaView;
    private List<Fruit> mFruit;
    private LayoutInflater inflater;
    private MyGridViewAdapter adapter;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        griaView=(GridView) findViewById(R.id.gridView_id);
        inflater=getLayoutInflater();
        ininFruit();


        adapter=new MyGridViewAdapter(mFruit, inflater);

        griaView.setAdapter(adapter);


    }

    public List<Fruit> ininFruit()
    {
        mFruit = new ArrayList<Fruit>();


        for (int i = 0; i < 5; i++) {

            Fruit fish = new Fruit("鱼", R.mipmap.fish);
            Fruit jellyfish = new Fruit("jelly鱼", R.mipmap.jelly_fish);
            Fruit kbugbuster = new Fruit("kbugbuster", R.mipmap.kbugbuster);
            Fruit penguin = new Fruit("penguin", R.mipmap.penguin);
            Fruit pig = new Fruit("penguin", R.mipmap.penguin);
            Fruit poweranimal = new Fruit("poweranimal", R.mipmap.power_animal);

            mFruit.add(fish);
            mFruit.add(jellyfish);
            mFruit.add(kbugbuster);
            mFruit.add(penguin);
            mFruit.add(pig);
            mFruit.add(poweranimal);


        }



        return mFruit;

    }


}

AndroidManifest.xml代码：

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="com.example.administrator.mygridview" >

    <application
        android:allowBackup="true"
        android:icon="@mipmap/fish"
        android:label="@string/app_name"
        android:theme="@style/AppTheme" >
        <activity
            android:name=".MainActivity"
            android:label="@string/app_name" >
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />

                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
        </activity>
    </application>

</manifest>

小结：

学习GridView，其基本思想都是一样的，想法设法得到一个adapter，然后去加载这个适配器。。