android - 如何从列表中删除复选框项目

Question

我在列表中有 50 个列表项。现在我已经选中了 10 个项目，那么当我单击删除按钮时如何从 ListView 中删除(删除)这 10 个选中的项目。

这是我的代码

请查看我的代码和响应错误在哪里:

public class BookmarksJokes extends Activity implements OnClickListener,
    OnItemClickListener {
ListView lv;
Button btn_delete;
public String TAG = "horror";
private SQLiteDatabase db;
public static final String PREFS_NAME = "MyPreferences";
static String[] tempTitle = new String[100];
static String[] tempBody = new String[100];
private static boolean bRequiresResponse;

private static class EfficientAdapter extends BaseAdapter {
    private LayoutInflater mInflater;

    public EfficientAdapter(Context context) {
        mInflater = LayoutInflater.from(context);

    }
    public int getCount() {
        return tempTitle.length;
    }

    public Object getItem(int position) {
        return position;
    }

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

    public View getView(int position, View convertView, ViewGroup parent) {
        ViewHolder holder;
        if (convertView == null) {
            convertView = mInflater.inflate(R.layout.bookmarks_list_item,
                    null);
            holder = new ViewHolder();
            holder.text1 = (TextView) convertView
                    .findViewById(R.id.title);
            holder.text2 = (TextView) convertView
                    .findViewById(R.id.body);
             holder.checkBox = (CheckBox) convertView.findViewById(R.id.checkbox);

            convertView.setTag(holder);
        } else {
            holder = (ViewHolder) convertView.getTag();
        }

        holder.text1.setText(tempTitle[position]);
        holder.text2.setText(tempBody[position]);
        // bRequiresResponse = checkBox.isChecked();
        return convertView;
    }

    static class ViewHolder {
        TextView text1;
        TextView text2;
        CheckBox checkBox;
    }
}

@Override
protected void onCreate(Bundle savedInstanceState) {

    super.onCreate(savedInstanceState);
    setContentView(R.layout.bokmarksjoks);

    try {
        db = (new DatabaseHelper(this)).getWritableDatabase();
    } catch (IOException e) {
        e.printStackTrace();
    }
    setUpViews();

    title = (TextView) findViewById(R.id.body);
    SharedPreferences pref = getSharedPreferences(PREFS_NAME, 0);

    //String ids = pref.getString("jid", "");
    String one = pref.getString("title", "");
    String two = pref.getString("body", "");

    tempTitle = one.split(",");
    tempBody = two.split(",");
    lv.setAdapter(new EfficientAdapter(this));
}

private void setUpViews() {
    lv = (ListView) findViewById(R.id.list);
    btn_delete = (Button) findViewById(R.id.delete);
    btn_delete.setOnClickListener(this);
    // checkbox = (CheckBox) findViewById(R.id.checkbox);

}
private void removeData(){
//int pos= getIntent().getIntExtra("POSITION", 0);
//lv.removeViewAt(pos);
// notifyAll();*/
//  int pos= getIntent().getIntExtra("POSITION", 0);
//  if(checkBox.isChecked()){
//      Log.d(TAG, " checked d]"+pos);
//      Toast.makeText(this, "checked "+pos, Toast.LENGTH_SHORT).show();
//  }
}
public void onClick(View v) {
    switch (v.getId()) {
        case R.id.delete:
        AlertDialog.Builder alt_bld = new AlertDialog.Builder(this);
        alt_bld.setMessage("Are you Sure want to delete all checked jok ?")
                .setCancelable(false)
                .setPositiveButton("Yes",
                        new DialogInterface.OnClickListener() {
                            public void onClick(DialogInterface dialog,
                                    int id) {
                                //removeJok();

                            }
                        })
                .setNegativeButton("No",
                        new DialogInterface.OnClickListener() {
                            public void onClick(DialogInterface dialog,
                                    int id) {
                                dialog.cancel();
                            }
                        });
        AlertDialog alert = alt_bld.create();
        alert.setTitle("Delete Jokes");
        alert.show();
    case R.id.checkbox:

    default:
        break;
    }

}

public void onItemClick(AdapterView<?> arg0, View view, int position,
        long ids) {

    try {

    //   checkBox = (CheckBox)view.findViewById(R.id.checkbox);
    //   checkBox.setChecked(true);

        Intent intent = new Intent(BookmarksJokes.this,
                BookmarkJokesDetails.class);

        intent.putExtra("POSITION", position);
        intent.putExtra("ID", ids);
        Cursor cursor = (Cursor) adapter.getItem(position);

        intent.putExtra("_ID",
                cursor.getInt(cursor.getColumnIndex("_id")));

        startActivity(intent);
    } catch (Exception e) {
        e.printStackTrace();
    }

    Toast.makeText(BookmarksJokes.this,
            "Item in position " + position + " clicked", Toast.LENGTH_LONG)
            .show();
}
}

这是我的完整代码:

http://pastebin.com/LB2WKHMP

Answer 1

我在我的一个应用程序中执行了相同的任务。

你应该做的是使用一个与列表项大小相同的ArrayList，默认情况下每个项目包含0。现在，在您的 Efficient Adapter 中，为选中的每个复选框在 arrayList 中的特定位置分配 1。最后单击 delete 按钮，遍历 ArrayList 并从列表中删除所有那些在该 ArrayList 中那个位置包含 1 的项目，最后调用 notifyDatasetChanged() 列表的方法 以便列表得到刷新和显示新列表。

下面是一些示例代码，可以让您对此有更好的了解:

 ArrayList<Integer> checks=new ArrayList<Integer>();

现在在onCreate方法中

for(int b=0;b<tempTitle.length;b++){
    checks.add(b,0);  //assign 0 by default in each position of ArrayList
        } 

现在在您的 efficientAdapter 的 getView 方法中

 public View getView(int position, View convertView, ViewGroup parent) {
        ViewHolder holder;
        if (convertView == null) {
            convertView = mInflater.inflate(R.layout.bookmarks_list_item,
                    null);
            holder = new ViewHolder();
            holder.text1 = (TextView) convertView
                    .findViewById(R.id.title);
            holder.text2 = (TextView) convertView
                    .findViewById(R.id.body);
             holder.checkBox = (CheckBox) convertView.findViewById(R.id.checkbox);

            convertView.setTag(holder);
        } else {
            holder = (ViewHolder) convertView.getTag();
        }

           holder.checkBox.setOnClickListener(new OnClickListener() {

            public void onClick(View v) {
                // TODO Auto-generated method stub

                if(((CheckBox)v).isChecked()){
                  checks.set(position, 1);
                }
                else{
                 checks.set(position, 0);
                }

            }
        });


        return convertView;
    }

最后点击删除按钮:

     delete.setOnClickListener(new OnClickListener() {

    public void onClick(View v) {
    // TODO Auto-generated method stub

          for(int i=0;i<checks.size();i++){

    if(checks.get(i)==1){
          //remove items from the list here for example from ArryList 
          checks.remove(i);
           //similarly remove other items from the list from that particular postion
           i--;
        }
     }
    ((EfficientAdapter)lv.getAdapter()).notifyDataSetChanged();
  }
}

希望这能解决您的问题。