GridView的最后固定显示一个增加图片，点击图片动态增加内容item

public class GridViewAdapter extends BaseAdapter {  

    private Context context;  

    private List<Integer> list;  

    LayoutInflater layoutInflater;  

    private ImageView mImageView;  

  

    public GridViewAdapter(Context context, List<Integer> list) {  

        this.context = context;  

        this.list = list;  

        layoutInflater = LayoutInflater.from(context);  

    }  

  

    @Override  

    public int getCount() {  

        return list.size()+1;//注意此处  

    }  

  

    @Override  

    public Object getItem(int position) {  

        return list.get(position);  

    }  

  

    @Override  

    public long getItemId(int position) {  

        return position;  

    }  

  

    @Override  

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

  

        convertView = layoutInflater.inflate(R.layout.grid_item, null);  

        mImageView = (ImageView) convertView.findViewById(R.id.item);  

        if (position < list.size()) {  

            mImageView.setBackgroundResource(list.get(position));  

        }else{  

            mImageView.setBackgroundResource(R.drawable.pic3);//最后一个显示加号图片  

        }  

        return convertView;  

    }  

  

}  

==========================================================

public class MainActivity extends ActionBarActivity {  

    private List<Integer> mDatas;  

private GridView mGridView;  

private GridViewAdapter adapter;  

    @Override  

    protected void onCreate(Bundle savedInstanceState) {  

        super.onCreate(savedInstanceState);  

        setContentView(R.layout.activity_main);  

        mGridView=(GridView) findViewById(R.id.gv_test);  

          

        initDatas();  

        adapter=new GridViewAdapter(MainActivity.this,mDatas);  

        mGridView.setAdapter(adapter);  

        mGridView.setOnItemClickListener(new OnItemClickListener() {  

  

            @Override  

            public void onItemClick(AdapterView<?> parent, View view,  

                    int position, long id) {  

                if(position==parent.getChildCount()-1){  

                    mDatas.add(R.drawable.pic1);  

                    Toast.makeText(MainActivity.this, "您点击了添加", 1).show();  

                    adapter=new GridViewAdapter(MainActivity.this, mDatas);  

                    mGridView.setAdapter(adapter);  

                    adapter.notifyDataSetChanged();  

                }  

                  

            }  

        });  

          

    }  

    private void initDatas() {  

        mDatas=new ArrayList<>();  

        mDatas.add(R.drawable.pic1);  

        mDatas.add(R.drawable.pic1);  

        mDatas.add(R.drawable.pic1);  

        mDatas.add(R.drawable.pic1);  

        mDatas.add(R.drawable.pic1);  

          

    }  

  

      

    }  

=========================================

main.xml布局

<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/gv_test"  

        android:numColumns="3"  

        android:layout_width="match_parent"  

        android:layout_height="match_parent" />  

  

</RelativeLayout>  

=============================================

grid_item布局

<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/item"  

        android:layout_width="wrap_content"  

        android:layout_height="wrap_content" />