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  • Android为ListView的Item设置不同的布局

    MainActivity如下:

    package cc.testlistview;
    import java.util.ArrayList;
    import java.util.HashMap;
    import android.os.Bundle;
    import android.view.View;
    import android.widget.AdapterView;
    import android.widget.AdapterView.OnItemClickListener;
    import android.widget.ListView;
    import android.app.Activity;
    /**
     * Demo描述:
     * 为ListView的Item设置不同的布局.
     * 例如在该例子中ListView的第一个Item显示一张
     * 图片,其余的Item都显示文字.
     * 
     * 为了达到此目的需要重写BaseAdapter中的
     * 1 getViewTypeCount()和getItemViewType(int position)方法.
     *   1.1在getViewTypeCount中指定一共有几种不同的item
     *      在此返回2即可.
     *   1.2在getItemViewType(int position)中需要依据position的不同
     *      返回不同的Type.
     * 2 在getView()方法中针对不同的Type为Item设置布局
     *   2.1得到当前位置(position)时的Type即代码:
     *       currentType= getItemViewType(position);
     *   2.2依据Type的不同为Item设置布局
     * 
     * 参考资料:
     * 1 http://blog.csdn.net/yueyue369/article/details/6115552
     * 2 http://blog.sina.com.cn/s/blog_5da93c8f0100wx4v.html
     *   Thank you very much
     */
    public class MainActivity extends Activity {
        private ListView mListView;
        private HashMap<String, Object> mHashMap;
    	private ArrayList<HashMap<String, Object>> mArrayList;
    	@Override
    	protected void onCreate(Bundle savedInstanceState) {
    		super.onCreate(savedInstanceState);
    		setContentView(R.layout.main);
    		init();
    	}
    	private void init(){
    		mArrayList=new ArrayList<HashMap<String,Object>>();
    		mListView=(ListView) findViewById(R.id.listview);
    		addDataForListView();
    		mListView.setAdapter
    		(new ListViewAdapter(MainActivity.this, mArrayList, R.layout.othersitem, new String []{"content"}, new int []{R.id.textView}));
    		mListView.setOnItemClickListener(new ItemClickListenerImpl());
    	}
    	private void addDataForListView(){
    		for (int i = 0; i < 30; i++) {
    			mHashMap=new HashMap<String, Object>();
    			mHashMap.put("content", "This is ---> "+i);
    			mArrayList.add(mHashMap);
    		}
    	}
    
    	private class ItemClickListenerImpl implements OnItemClickListener {
    		@Override
    		public void onItemClick(AdapterView<?> parent, View view, int position,long arg) {
    			System.out.println("OnItemClickListener position="+position);
    
    		}
    	}
    }
    


    ListViewAdapter如下:

    package cc.testlistview;
    import java.util.List;
    import java.util.Map;
    import android.content.Context;
    import android.view.LayoutInflater;
    import android.view.View;
    import android.view.View.OnClickListener;
    import android.view.ViewGroup;
    import android.widget.BaseAdapter;
    import android.widget.ImageView;
    import android.widget.TextView;
    
    public class ListViewAdapter extends BaseAdapter {
    	private List<? extends Map<String, ?>> mArrayList;
    	private int resource;
    	private LayoutInflater mLayoutInflater;
    	
    	private final int TYPE_COUNT=2;
    	private final int FIRST_TYPE=0;
    	private final int OTHERS_TYPE=1;
    	private int currentType;
    	public ListViewAdapter(Context context,List<? extends Map<String, ?>> data, int resource, String[] from,int[] to) {
    		this.mArrayList=data;
    		this.resource=resource;
    		mLayoutInflater=(LayoutInflater) context.getSystemService(context.LAYOUT_INFLATER_SERVICE);
    	}
    	
    	@Override
    	public int getCount() {
    		if (mArrayList==null) {
    			return 0;
    		} else {
    			return (mArrayList.size()+1);
    		}
    		
    	}
    	
    	@Override
    	public Object getItem(int position) {
    		if (mArrayList==null) {
    			return null;
    		} else {
    			if (position>0) {
    				return mArrayList.get(position-1);
    			} else {
    				return mArrayList.get(position+1);
    			}
    		}
    	}
    	
    	@Override
    	public long getItemId(int position) {
    		return position;
    	}
    	
    	///////////////////////////////////////////////////////
    	@Override
    	public int getViewTypeCount() {
    		return TYPE_COUNT;
    	}
    	
    	@Override
    	public int getItemViewType(int position) {
    		if (position==0) {
    			return FIRST_TYPE;
    		} else {
    			return OTHERS_TYPE;
    		}
    	}
       ///////////////////////////////////////////////////////
    	
        @Override
    	public View getView(int position, View convertView, ViewGroup parent) {
    		View firstItemView = null;
    	    View othersItemView=null;
    	    //获取到当前位置所对应的Type
    	    currentType= getItemViewType(position);
    	    System.out.println("type="+currentType);
    		if (currentType== FIRST_TYPE) {
    			firstItemView = convertView;
    			FirstItemViewHolder firstItemViewHolder=null;
    			if (firstItemView==null) {
    				System.out.println("firstItemView==null ");
    				firstItemView = mLayoutInflater.inflate(R.layout.firstitem,null);
    				firstItemView.setOnClickListener(new OnClickListener() {
    					@Override
    					public void onClick(View view) {
    						System.out.println("=====click first item=======");
    					}
    				});
    				firstItemViewHolder=new FirstItemViewHolder();
    				firstItemViewHolder.imageView=(ImageView) firstItemView.findViewById(R.id.imageView);
    				firstItemView.setTag(firstItemViewHolder);
    
    			} else {
    				System.out.println("firstItemView!=null ");
    				System.out.println("111 getClass="+firstItemView.getTag().getClass().toString());
    				firstItemViewHolder=(FirstItemViewHolder) firstItemView.getTag();
    			}
    			
    			if (firstItemViewHolder.imageView!=null) {
    				firstItemViewHolder.imageView.setImageResource(R.drawable.ic_launcher);
    			}
    			
    			convertView=firstItemView;
    
    		} else {
    			othersItemView = convertView;
    			OthersViewHolder othersViewHolder=null;
    			if (othersItemView==null) {
    				System.out.println("othersItemView==null ");
    				othersItemView = mLayoutInflater.inflate(R.layout.othersitem,null);
    				othersViewHolder=new OthersViewHolder();
    				othersViewHolder.textView=(TextView) othersItemView.findViewById(R.id.textView);
    				othersItemView.setTag(othersViewHolder);
    			} else {
    				System.out.println("othersItemView!=null ");
    				System.out.println("222 getClass="+othersItemView.getTag().getClass().toString());
    				othersViewHolder=(OthersViewHolder) othersItemView.getTag();
    			}
    			
    			if (mArrayList!=null) {
    				if (othersViewHolder.textView!=null) {
    					othersViewHolder.textView.setText((String)(mArrayList.get(position-1).get("content")));
    				}
    				
    			}
    			
    			convertView=othersItemView;
    
    		}
    
    		return convertView;
    	}
        
      
        //第一个Item的ViewHolder
        private class FirstItemViewHolder{
        	ImageView imageView;
        }
        
        //除第一个Item以外其余Item的ViewHolder
        private class OthersViewHolder{
        	TextView textView;
        }
    }
    


     

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  • 原文地址:https://www.cnblogs.com/suncoolcat/p/3357824.html
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