Android课程---关于GridView网格视图的学习

<?xml version="1.0" encoding="utf-8"?>
<GridView xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:id="@+id/gv_1"
android:numColumns="auto_fit"
android:verticalSpacing="10dp"
android:horizontalSpacing="10dp"
android:columnWidth="100dp"
android:gravity="center"
android:stretchMode="columnWidth">

<!--stretchMode:缩放模式  columnWidth:根据列宽来设-->

</GridView>

package com.hanqi.test5;

import android.os.Bundle;
import android.support.v7.app.AppCompatActivity;
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.Toast;

public class UIActivity6 extends AppCompatActivity {

int[] imid;

@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_ui6);

GridView gv_1 =(GridView)findViewById(R.id.gv_1);

imid = new int[]{R.drawable.yuantu,R.drawable.yuantu,R.drawable.yuantu,R.drawable.yuantu,R.drawable.yuantu
,R.drawable.yuantu,R.drawable.yuantu,R.drawable.yuantu};

gv_1.setAdapter(new MyBaseAdapter());
gv_1.setOnItemClickListener(new AdapterView.OnItemClickListener() {
@Override
public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
Toast.makeText(UIActivity6.this, "position =" + position, Toast.LENGTH_SHORT).show();
}
});

}
class MyBaseAdapter extends BaseAdapter
{
@Override
public int getCount() {
return imid.length;
}

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

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

@Override
public View getView(int position, View convertView, ViewGroup parent) {
//获取数据
int Imageid = imid[position];
//构造视图
ImageView iv_1 = null;
if (convertView == null)
{
iv_1 = new ImageView(UIActivity6.this);

iv_1.setLayoutParams(new GridView.LayoutParams(100,100));  //属性设置
iv_1.setScaleType(ImageView.ScaleType.FIT_XY);  //FIT_XY:自动全部充满

}
else
{
iv_1 = (ImageView)convertView;  //强转
}
iv_1.setImageResource(Imageid);

return iv_1;
}
}
}