Android GridView的使用
(1)GridView布局,里面比较重要的参数有numColums,很明显这个参数就是定义GridView的列数,示例布局如下:
<?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" >
<GridView
android:id="@+id/myGridView"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:numColumns="3">
</GridView>
</RelativeLayout>
(2)现在我们有了布局,该是给它添加数据的时候了,我们给它添加一张图片和一个图名,即就是每个Item中将包含一个ImageView和一个TextView。
a.我们需要先定义一下这个布局:
<?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:id="@+id/myImage"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:contentDescription="@string/ImageDescription"
>
</ImageView>"
<TextView
android:id="@+id/txt_title"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:textSize="24sp"
android:text="示例">
</TextView>"
</LinearLayout>
b.接下来为GridView定义适配器类
package com.example.mgridview;
import java.util.List;
import android.content.Context;
import android.graphics.Bitmap;
import android.graphics.drawable.Drawable;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.BaseAdapter;
import android.widget.ImageView;
import android.widget.TextView;
public class myGridViewAdapter extends BaseAdapter{
private LayoutInflater inflater;
private List<Drawable> bitmap;
private List<String> mStr;
public myGridViewAdapter(Context context)
{
inflater=LayoutInflater.from(context);
}
//这里很关键,该参数控制着GridView中数据的数目
@Override
public int getCount() {
// TODO Auto-generated method stub
return 7;
}
@Override
public Object getItem(int arg0) {
// TODO Auto-generated method stub
return null;
}
@Override
public long getItemId(int arg0) {
// TODO Auto-generated method stub
return 0;
}
@Override
public View getView(int position, View convertView, ViewGroup parent) {
// TODO Auto-generated method stub
ListItemView listItemView = null;
if (convertView == null) {
listItemView = new ListItemView();
convertView = inflater.inflate(R.layout.grid_item_layout, null);
listItemView.image=(ImageView)convertView.findViewById(R.id.myImage);
listItemView.txtDes=(TextView)convertView.findViewById(R.id.txt_title);
convertView.setTag(listItemView);
}else {
listItemView = (ListItemView) convertView.getTag();
}
listItemView.clear();
listItemView.image.setBackgroundDrawable(bitmap.get(position));
listItemView.txtDes.setText(mStr.get(position));
return convertView;
}
public List<Drawable> getBitmap() {
return bitmap;
}
public void setBitmap(List<Drawable> bitmap) {
this.bitmap = bitmap;
}
public List<String> getmStr() {
return mStr;
}
public void setmStr(List<String> mStr) {
this.mStr = mStr;
}
private final class ListItemView {
private ImageView image;
private TextView txtDes;
public void clear()
{
image.setBackgroundResource(R.drawable.img_downloading);
txtDes.setText("null");
}
}
}
C.接下来该是为GridView添加适配器的时候了
package com.example.gridview;
import java.util.ArrayList;
import java.util.List;
import android.os.Bundle;
import android.app.Activity;
import android.graphics.Bitmap;
import android.graphics.drawable.Drawable;
import android.view.Menu;
import android.widget.GridView;
public class MainActivity extends Activity {
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
init();
}
private void init()
{
GridView myGridView=(GridView)findViewById(R.id.myGridView);
List<Drawable> bitmap=new ArrayList<Drawable>();
bitmap.add(this.getResources().getDrawable(R.drawable.kbsj));
bitmap.add(this.getResources().getDrawable(R.drawable.kbsj));
bitmap.add(this.getResources().getDrawable(R.drawable.kfxyy));
bitmap.add(this.getResources().getDrawable(R.drawable.rhxpt));
bitmap.add(this.getResources().getDrawable(R.drawable.kbsj));
bitmap.add(this.getResources().getDrawable(R.drawable.kfxyy));
bitmap.add(this.getResources().getDrawable(R.drawable.rhxpt));
List<String> mStr=new ArrayList<String>();
mStr.add("示例1");
mStr.add("示例2");
mStr.add("示例3");
mStr.add("示例4");
myGridViewAdapter adapter=new myGridViewAdapter();
adapter.setBitmap(bitmap);
adapter.setmStr(mStr);
myGridView.setAdapter(adapter);
}
}
3.好了。接下来可以运行看一下结果啦!