android用户界面组件Widget网格视图GridView

GridView按照行列的方式来显示内容。一般适合显示图标。图片等内容，主要用于设置Adapter。

通过基础类BaseAdapter类，重写getView()方法来设置图片显示格式。

/Chapter04_UI_GridView01/src/com/amaker/test/MainActivity.java

package com.amaker.test;

import android.app.Activity;
import android.content.Context;
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 gv;
    
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);
        gv = (GridView)findViewById(R.id.GridView01);
        gv.setNumColumns(4);
        // gv.setNumColumns(3);
        // String[] strs = {"a","a1","a2","b","b1","b2","c","c1","c2"};
        // ArrayAdapter<String> adapter = new ArrayAdapter<String>(this,android.R.layout.simple_gallery_item,strs);
        gv.setAdapter(new MyAdapter(this));
        
    }
    
    class MyAdapter extends BaseAdapter{
        
        private Integer[] imgs = {
                R.drawable.gallery_photo_1,
                R.drawable.gallery_photo_2,
                R.drawable.gallery_photo_3,
                R.drawable.gallery_photo_4,
                R.drawable.gallery_photo_5,
                R.drawable.gallery_photo_6,
                R.drawable.gallery_photo_7,
                R.drawable.gallery_photo_8,
                
                R.drawable.gallery_photo_1,
                R.drawable.gallery_photo_2,
                R.drawable.gallery_photo_3,
                R.drawable.gallery_photo_4,
                R.drawable.gallery_photo_5,
                R.drawable.gallery_photo_6,
                R.drawable.gallery_photo_7,
                R.drawable.gallery_photo_8
        };
        Context context;
        MyAdapter(Context context){
            this.context = context;
        }
        public int getCount() {
            return imgs.length;
        }

        public Object getItem(int item) {
            return item;
        }

        public long getItemId(int id) {
            return id;
        }

        public View getView(int position, View convertView, ViewGroup parent) {
             ImageView imageView;
                if (convertView == null) {
                    imageView = new ImageView(context);
                    imageView.setLayoutParams(new GridView.LayoutParams(45, 45));
                    imageView.setAdjustViewBounds(false);
                    imageView.setScaleType(ImageView.ScaleType.CENTER_CROP);
                    imageView.setPadding(8, 8, 8, 8);
                } else {
                    imageView = (ImageView) convertView;
                }
                imageView.setImageResource(imgs[position]);
                return imageView;
        }
    }
}