如何刪除android中的自定義listview項目

Question

我想刪除列表中的listview項目..但是當我點擊開啓按鈕時什麼也沒有發生。請告訴我在哪裏，我在做錯誤的...此代碼可以添加項目，但只刪除項目傾斜...

//列表視圖的Java

public class MemberActivity extends AppCompatActivity implements BaseColumns { 
ListView mylist; 

@Override 
protected void onCreate(Bundle savedInstanceState) { 
    super.onCreate(savedInstanceState); 
    setContentView(R.layout.activity_member); 

    final ListView listview; 
    final ListViewAdapter adapter; 
    //final ArrayList<String> items = new ArrayList<String>(); 


    mylist = (ListView) findViewById(R.id.listview1); 
    final LinearLayout linewarLayout1 = (LinearLayout) findViewById(R.id.addmember); 
    final LinearLayout linewarLayout2 = (LinearLayout) findViewById(R.id.buttongroup); 


    adapter = new ListViewAdapter(); 


    listview = (ListView) findViewById(R.id.listview1); 
    final View header = getLayoutInflater().inflate(R.layout.listview_header, null, false); 

    listview.setAdapter(adapter); 

    Button addButton = (Button) findViewById(R.id.add); 
    addButton.setOnClickListener(new Button.OnClickListener() { 
     public void onClick(View v) { 
      mylist.setVisibility(View.INVISIBLE); 
      linewarLayout2.setVisibility(View.INVISIBLE); 
      linewarLayout1.setVisibility(View.VISIBLE); 
     } 
    }); 

    final EditText name = ((EditText) findViewById(R.id.etName)); 
    final EditText ID = ((EditText) findViewById(R.id.etID)); 
    final EditText Major = ((EditText) findViewById(R.id.etMajor)); 

    Button btnDone = (Button) findViewById(R.id.btnDone); 
    btnDone.setOnClickListener(new Button.OnClickListener() { 
     public void onClick(View v) { 

      //TextView cnttxt = (TextView)findViewById(R.id.count); 
      //cnttxt.setText(adapter.getCount()); 

      adapter.addItem(name.getText().toString(), ID.getText().toString(), Major.getText().toString()); 
      name.setText(""); 
      ID.setText(""); 
      Major.setText(""); 
      Toast.makeText(getApplicationContext(), "add.", Toast.LENGTH_LONG).show(); 
      mylist.setVisibility(View.VISIBLE); 
      linewarLayout2.setVisibility(View.VISIBLE); 
      linewarLayout1.setVisibility(View.INVISIBLE); 
     } 
    }); 

    Button btnCancel = (Button) findViewById(R.id.btnCancel); 
    btnCancel.setOnClickListener(new Button.OnClickListener() { 
     public void onClick(View v) { 
      name.setText(""); 
      ID.setText(""); 
      Major.setText(""); 
      mylist.setVisibility(View.VISIBLE); 
      linewarLayout2.setVisibility(View.VISIBLE); 
      linewarLayout1.setVisibility(View.INVISIBLE); 
     } 
    }); 

    // delete button 
    Button deleteButton = (Button) findViewById(R.id.delete); 
    deleteButton.setOnClickListener(new Button.OnClickListener() { 
     public void onClick(View v) { 
      int count, checked; 
      count = adapter.getCount(); 

      if (count > 0) { 

       listview.setChoiceMode(AbsListView.CHOICE_MODE_SINGLE); 
       checked = listview.getCheckedItemPosition(); 

       if (checked > -1 && checked < count) { 

        adapter.removeitem(checked); 


        listview.clearChoices(); 


        adapter.notifyDataSetChanged(); 
       } 
      } 
     } 
    }); 

    listview.setOnItemClickListener(new AdapterView.OnItemClickListener() { 
     @Override 
     public void onItemClick(AdapterView parent, View v, int position, long id) { 
      // get item 
      ListViewItem item = (ListViewItem) parent.getItemAtPosition(position); 

      String nameStr = item.getname(); 
      String IDStr = item.getID(); 
      String majorStr = item.getmajor(); 

     } 
    }); 



} 

} //適配器

public class ListViewAdapter extends BaseAdapter { 
private ArrayList<ListViewItem> listViewItemList = new ArrayList<ListViewItem>(); 

public ListViewAdapter() { 

} 

@Override 
public int getCount() { 
    return listViewItemList.size(); 
} 

@Override 
public View getView(int position, View convertView, ViewGroup parent) { 
    final int pos = position; 
    final Context context = parent.getContext(); 

    if (convertView == null) { 
     LayoutInflater inflater = (LayoutInflater) context.getSystemService(Context.LAYOUT_INFLATER_SERVICE); 
     convertView = inflater.inflate(R.layout.listview_item, parent, false); 
    } 

    TextView nameTextView = (TextView) convertView.findViewById(R.id.list_name); 
    TextView IDTextView = (TextView) convertView.findViewById(R.id.list_ID); 
    TextView majorTextView = (TextView) convertView.findViewById(R.id.list_major); 

    ListViewItem listViewItem = listViewItemList.get(position); 

    nameTextView.setText(listViewItem.getname()); 
    IDTextView.setText(listViewItem.getID()); 
    majorTextView.setText(listViewItem.getmajor()); 

    return convertView; 
} 

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

@Override 
public Object getItem(int position) { 
    return listViewItemList.get(position); 
} 

public void removeitem(int position) { 
    listViewItemList.remove(position); 
    notifyDataSetChanged(); 
} 

public void addItem(String name, String ID, String major) { 
    ListViewItem item = new ListViewItem(); 

    item.setname(name); 
    item.setID(ID); 
    item.setmajor(major); 

    listViewItemList.add(item); 

    notifyDataSetChanged(); 
} 

}

// ListViewItem的java的

public class ListViewItem { 
private String nameStr; 
private String IDStr; 
private String majorStr; 

public void setname(String name) { 
    nameStr = name; 
} 

public void setID(String ID) { 
    IDStr = ID; 
} 

public void setmajor(String major) { 
    majorStr = major; 
} 

public String getname() { 
    return this.nameStr; 
} 

public String getID() { 
    return this.IDStr; 
} 

public String getmajor() { 
    return this.majorStr; 
} 

}

Answer 1

更新您的代碼如下。設置選擇模式爲CHOICE_MODE_SINGLE當您創建列表視圖和設置適配器之前。從按鈕點擊刪除CHOICE_MODE_SINGLE。

listview = (ListView) findViewById(R.id.listview1); 
listview.setChoiceMode(AbsListView.CHOICE_MODE_SINGLE); 
listview.setAdapter(adapter); 

另外，你需要在setItemChecked列表視圖的onItemClick。

請查看下面的示例代碼。

public class MainActivity extends Activity { 

private ListView mListView; 
private String[] mData = new String[] { "xxx", "yyy", "zzz", "aaa" }; 
private BaseAdapter mAdapter; 
private int mLastCorrectPosition = -1; 
private int mButtonPosition = 0; 

@Override 
public void onCreate(Bundle savedInstanceState) { 
    super.onCreate(savedInstanceState); 
    setContentView(R.layout.activity_main); 

    mListView = (ListView) findViewById(R.id.list_view); 
    mListView.setChoiceMode(ListView.CHOICE_MODE_SINGLE); 

    mAdapter = new ArrayAdapter<String>(this, 
        android.R.layout.simple_list_item_activated_1, mData); 
    mListView.setAdapter(mAdapter); 
    mListView.setSelector(new ColorDrawable(0)); 

    mListView.setOnItemClickListener(new OnItemClickListener() { 

     @Override 
     public void onItemClick(AdapterView<?> parent, View view, 
         int position, long id) { 
      if (position == mButtonPosition) { 
       if (mLastCorrectPosition != -1) { 
        mListView.setItemChecked(mLastCorrectPosition, true); 
       } 
       else { 
        mListView.setItemChecked(mButtonPosition, false); 
       } 
       // here show dialog 
      } 
      else { 
       mLastCorrectPosition = position; 
       // here refresh fragment 
      } 
     } 
    }); 
} 
}