Listview結合checkbox實現刪除功能

效果圖

實現要點：

1 Listview是一個動態的組件，實現監聽Listview裏的動作需要用到BaseAdapter類

2 數據存儲結構ArrayList<HashMap<String, String>> list， 第一個string存放flag，用以判斷是否選中；第二個string存放msg

3 一旦數據有變，必須使用mAdapter.notifyDataSetChanged(); 否則view無法得知數據變化，從而會報錯

一共由以下文件組成（僅核心部分，參考慎用）

JAVA

    Button btnDelete;
    ListView lv;
		Context mContext;
		MyListAdapter adapter; 
		private ArrayList<HashMap<String, String>> list;
		
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState); 
        
        requestWindowFeature(Window.FEATURE_NO_TITLE); 
        setContentView(R.layout.activity_carton_no_main);
        SysApplication.getInstance().addActivity(this); 
        
        btnDelete = (Button)findViewById(R.id.ctn_no_scan_delete_btn); 
        lv = (ListView)findViewById(R.id.carton_no_list);
        
				list = new ArrayList<HashMap<String, String>>();  
				mAdapter = new MyListAdapter(list, this);
				lv.setAdapter(mAdapter);
				
				//insert something
				HashMap<String, String> map = new HashMap<String, String>();
  			map.put("content", 'test');
  			map.put("flag", "false");
  			list.add(map); 
  			
  			btnDelete.setOnClickListener(new View.OnClickListener() { 
					@Override
					public void onClick(View v) { 
						Iterator<HashMap<String, String>> iterator = list.iterator();
						while (iterator.hasNext()) {
							HashMap<String, String> temp = iterator.next();
							if (temp.get("flag").equals("true")) {
								iterator.remove();
							}
						}
						checkNum = 0;
						//if you have changed list, please excute mAdapter.notifyDataSetChanged(); 
						dataChanged();
					}
				});
  			
  			lv.setOnItemClickListener(new OnItemClickListener() {
					@Override
					public void onItemClick(AdapterView<?> arg0, View arg1, int arg2,
							long arg3) {  
						ViewHolder holder = (ViewHolder) arg1.getTag();  
						holder.cb.toggle();
						
						//store checkbox's status 
						if (holder.cb.isChecked() == true) {
							list.get(arg2).put("flag", "true");
							checkNum++;
						} else {
							list.get(arg2).put("flag", "false");
							checkNum--;
						} 
					}
				});
    }
		public class MyListAdapter extends BaseAdapter{
		
				private ArrayList<HashMap<String, String>> list;
				 
				private Context context;
				 
				private LayoutInflater inflater = null;
				 
				public MyListAdapter(ArrayList<HashMap<String, String>> list, Context context){
					this.context = context;
					this.list = list;
					inflater = LayoutInflater.from(context);
				}
				
				@Override
				public int getCount() {
					 
					return list.size();
				}
				@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){
					ViewHolder holder = null;
					if (convertView == null) {
						holder = new ViewHolder();
						convertView = inflater.inflate(R.layout.activity_carton_no_list, null);
						holder.tv = (TextView) convertView.findViewById(R.id.carton_no_list_name);
						holder.cb = (CheckBox) convertView.findViewById(R.id.carton_no_list_checked); 
						convertView.setTag(holder);
					} else { 
						holder = (ViewHolder) convertView.getTag();
					}
					//init view
					holder.tv.setText(list.get(position).get("content").toString()); 
					holder.cb.setChecked(list.get(position).get("flag").equals("true"));
					return convertView;
				}
				
				final class ViewHolder{
					TextView tv;
					CheckBox cb; 
				}
			}
		private void dataChanged(){
		
	  mAdapter.notifyDataSetChanged(); 
	  }

XML 

1/2

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:tools="http://schemas.android.com/tools"
    xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    android:background="@color/white"
    android:orientation="vertical" >
    
  <LinearLayout
     android:layout_width="wrap_content"
     android:layout_height="wrap_content"
     android:orientation="horizontal"
     android:descendantFocusability="blocksDescendants"> 
	  
      <CheckBox
        android:id="@+id/carton_no_list_checked"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:clickable="false"
        android:focusable="false"
        android:focusableInTouchMode="false"
        android:gravity="center_vertical" />

	  <TextView
	      android:id="@+id/carton_no_list_name"
	      android:layout_width="fill_parent"
	      android:layout_height="wrap_content"
	      android:layout_gravity="center"
	      android:layout_marginLeft="10dp"
	      android:layout_weight="1"
	      android:text="Name"
	      android:textColor="@color/viewfinder_mask"
	      android:textSize="20dp" />
	   
  </LinearLayout>
</LinearLayout>

2/2

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:tools="http://schemas.android.com/tools"
    xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:background="@color/white"
    android:orientation="vertical" >
 
	<LinearLayout  
	    android:orientation="vertical"
	    android:layout_width="match_parent"
	    android:layout_height="match_parent" 
	    android:layout_weight="0.1"> 
	    <ListView
	       android:id="@+id/carton_no_list"
	       android:layout_width="match_parent"
	       android:layout_height="fill_parent"/>
	</LinearLayout>
 	 	<LinearLayout
        android:id="@+id/LinearLayout1"
        android:layout_width="match_parent"
        android:layout_height="match_parent"   
        android:layout_weight="0.7"
        android:orientation="horizontal" >

        <Button
            android:id="@+id/ctn_no_scan_delete_btn"
            android:layout_width="match_parent"
            android:layout_height="50dp"
            android:layout_weight="0.1" 
            android:text="Delete" /> 
         
    </LinearLayout>  
</LinearLayout>

同理，實現radiobox，也是一樣的道理。

One thing leads to another...