安卓学习UI组件-GridView-常用属性与自定义适配器，图文排列

一.常用属性与自定义适配器。网格方式排列视图

图片应该设置大小一样

MainActivity.java

import android.app.Activity;
import android.content.Context;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.view.ViewGroup;
import android.widget.BaseAdapter;
import android.widget.GridView;
import android.widget.ImageView;

public class MainActivity extends Activity {

    private GridView gridView;
    /*GridView组件:
    *1.自定义适配器
    * （1）创建一个类，继承BaseAdapter类
    * （2）实现四个方法
    *    getCount:获取要显示的选项总数
    *    getItem:获取每一个选项
    *    getItemId:选项的ID值
    *    getView:该方法用来为每一个选项生成视图（ImageView）,该方法会被多次调用
    * */
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        gridView=(GridView)findViewById(R.id.gridView);
        //绑定适配器
       gridView.setAdapter(new MyAdapter(this));
    }


    //自定义适配器
    static class MyAdapter extends BaseAdapter
    {
//图片大小要一样
        private int[] images={R.mipmap.pic0,
                R.mipmap.pic1,
                R.mipmap.pic2,
                R.mipmap.pic3,
                R.mipmap.pic4,
                R.mipmap.pic5,
                R.mipmap.pic6,
                R.mipmap.pic7,
                R.mipmap.pic8,
                R.mipmap.pic9,
                R.mipmap.pic10,
                R.mipmap.pic11,
                R.mipmap.pic12,
                R.mipmap.pic13,
                R.mipmap.pic14,
                R.mipmap.pic15};
        private Context context;
        public MyAdapter(Context context)
        {
            this.context=context;
        }
        @Override
        public int getCount() {
            return images.length;
        }

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

        @Override
        public long getItemId(int position) {
            return position;
        }
      //关键 重复调用给每一个ITEM 填充
        @Override
        public View getView(int position, View convertView, ViewGroup parent) {
                ImageView iv=new ImageView(context);

            iv.setImageResource(images[position]);
            return iv;
        }
    }
}

<?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: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.administrator.myapplication.MainActivity">

    <GridView
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:id="@+id/gridView"
        android:numColumns="auto_fit"
        android:columnWidth="90dp"
         android:horizontalSpacing="10dp"
        android:verticalSpacing="10dp"
        android:stretchMode="columnWidth"
        android:gravity="center"
        android:layout_alignParentTop="true"
        android:layout_alignParentStart="true"
        />
</RelativeLayout>

二.带图片和文本视图的GridView

ManActivity.java

import android.app.Activity;
import android.content.Context;
import android.os.Bundle;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.AdapterView;
import android.widget.BaseAdapter;
import android.widget.GridView;
import android.widget.ImageView;
import android.widget.TextView;
import android.widget.Toast;

import org.w3c.dom.Text;

public class MainActivity2 extends Activity {
private GridView gridView;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main2);
        gridView= (GridView) findViewById(R.id.gridView2);
        gridView.setAdapter(new MyAdapter(this));
         gridView.setOnItemClickListener(new AdapterView.OnItemClickListener() {
             @Override
             public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
                 System.out.println("parent="+parent);
                 System.out.println("view="+view);//每一个选项的布局
                 System.out.println("position="+position);//位置
                 System.out.println("id=" + id);///id
                 TextView tv=(TextView)view.findViewById(R.id.textView);
                 Toast.makeText(MainActivity2.this,tv.getText(),Toast.LENGTH_SHORT).show();
             }
         });
    }

//静态类相当于一个外部类 不依赖于外部类的对象 比非静态内部类效率更高
    static class MyAdapter extends BaseAdapter{

    private String[] names={"转账","查询","金融","基金","国债","信用卡","商城","充值","红包"};
    private int[] images={R.mipmap.ic_launcher,
            R.mipmap.ic_launcher,
            R.mipmap.ic_launcher,
            R.mipmap.ic_launcher,
            R.mipmap.ic_launcher,
            R.mipmap.ic_launcher,
            R.mipmap.ic_launcher,
            R.mipmap.ic_launcher,
            R.mipmap.ic_launcher
    };


private Context context;
    public MyAdapter(Context context)
    {
this.context=context;
    }

        @Override
        public int getCount() {
            return names.length;
        }

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

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

        @Override
        public View getView(int position, View convertView, ViewGroup parent) {
            LayoutInflater inflater=LayoutInflater.from(context);
            View view=inflater.inflate(R.layout.item, null);
            ImageView iv= (ImageView) view.findViewById(R.id.imageView);
            TextView tv= (TextView) view.findViewById(R.id.textView);
            iv.setImageResource(images[position]);
            tv.setText(names[position]);


            return view;
        }
    }
}

activity_main.xml

<?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:paddingBottom="16dp"
    android:paddingLeft="16dp"
    android:paddingRight="16dp"
    android:paddingTop="16dp"
    tools:context="com.example.administrator.myapplication.MainActivity2">

    <GridView
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:id="@+id/gridView2"
        android:numColumns="4"
        android:horizontalSpacing="10dp"
        android:verticalSpacing="10dp"
        android:gravity="center"
        android:columnWidth="60dp"
        android:stretchMode="columnWidth"
        android:layout_alignParentTop="true"
        android:layout_alignParentStart="true" />
</RelativeLayout>

item.xml

<?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:orientation="vertical">

    <ImageView
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:id="@+id/imageView"
        android:layout_gravity="center"
        android:src="@mipmap/ic_launcher"/>

    <TextView
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_gravity="center"
        android:text="New Text"
        android:id="@+id/textView" />
</LinearLayout>