Question

好的，所以我一直在尝试让OnItemClickListener从列表项中检索值。目前正在注册点击，但价值未通过。这是我的代码的相关部分：

public class DiarySchedule extends ListActivity implements OnClickListener
{
    private DiaryDataSource datasource;
    private static final String TAG = "MAD Diary Schedule";
    private String delTitle;
    private String delDate;
    private String delTime;
    private String editTitle;
    private String editDate;
    private String editTime;

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

    datasource = new DiaryDataSource(this);
    datasource.open();

    List<DiaryEntry> values = datasource.getAllDiaryEntries();

    DiaryScheduleAdapter adapter = new DiaryScheduleAdapter(this,values);
    setListAdapter(adapter);

    registerForContextMenu(getListView());


}


public class DiaryScheduleAdapter extends ArrayAdapter<DiaryEntry>
{
    private LayoutInflater li;

    public DiaryScheduleAdapter(Context context, List<DiaryEntry> values) 
    {
        super(context, 0, values);
        li = (LayoutInflater) context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
    }

    @Override
    public View getView(int position, View convertView, ViewGroup parent) 
    {
        DiaryEntry diaryEntry = getItem(position);

        View v = convertView;
        if ( v == null ) 
        {
            v = li.inflate(R.layout.diary_schedule, null);
        }

        TextView date = (TextView)v.findViewById(R.id.scheduleListDate);
        String initialDate = diaryEntry.getDate();
        String formattedDate = ConvertToDate(initialDate);
        date.setText(formattedDate);

        TextView link = (TextView)v.findViewById(R.id.scheduleListLink);
        link.setText(" at ");

        TextView time = (TextView)v.findViewById(R.id.scheduleListTime);
        time.setText(diaryEntry.getTime());

        TextView title = (TextView)v.findViewById(R.id.scheduleListTitle);
        title.setText(diaryEntry.getTitle());

        v.setOnClickListener(new OnItemClickListener(position));

        return v;
    }

}


@Override
public boolean onCreateOptionsMenu (Menu menu)
{
    new MenuInflater(getApplication()).inflate(R.menu.diary_menu, menu);
    return (super.onCreateOptionsMenu(menu));
}

@Override
public boolean onOptionsItemSelected (MenuItem item)
{
    switch (item.getItemId())
    {
        case R.id.add:
            Intent intent = new Intent(DiarySchedule.this, DiaryAddEntry.class);
            startActivity(intent);
            break;
    }
    return super.onOptionsItemSelected(item);
}



@Override
public void onCreateContextMenu(ContextMenu menu, View v, ContextMenu.ContextMenuInfo menuInfo) 
{
    MenuInflater inflater = getMenuInflater();
    inflater.inflate(R.menu.diary_context_menu, menu);
}

@Override
public boolean onContextItemSelected(MenuItem item) 
{
    AdapterContextMenuInfo info = (AdapterContextMenuInfo) item.getMenuInfo();

    switch (item.getItemId())
    {
        case R.id.edit:
            Intent editIntent = new Intent(DiarySchedule.this, DiaryEditEntry.class);

            editTitle = (String) ((TextView) info.targetView.findViewById(R.id.scheduleListTitle)).getText();
            editDate = (String) ((TextView) info.targetView.findViewById(R.id.scheduleListDate)).getText();
            editDate = GetInfoConvertToDate(editDate);
            editTime = (String) ((TextView) info.targetView.findViewById(R.id.scheduleListTime)).getText();

            editIntent.putExtra("title", editTitle);
            editIntent.putExtra("date", editDate);
            editIntent.putExtra("time", editTime);

            startActivity(editIntent);
            break;

        case R.id.delete:
            delTitle = (String) ((TextView) info.targetView.findViewById(R.id.scheduleListTitle)).getText();
            delDate = (String) ((TextView) info.targetView.findViewById(R.id.scheduleListDate)).getText();
            delDate = GetInfoConvertToDate(delDate);
            delTime = (String) ((TextView) info.targetView.findViewById(R.id.scheduleListTime)).getText();

            Log.v(TAG, "Hopefully title is: " + delTitle + " with date of " + delDate + " and time of " + delTime);

            AlertDialog.Builder builder = new AlertDialog.Builder(this);
            builder.setMessage("Are you sure?").setPositiveButton("Yes", dialogClickListener)
                .setNegativeButton("No", dialogClickListener).show();

            break;
    }
    return super.onContextItemSelected(item);
}



DialogInterface.OnClickListener dialogClickListener = new DialogInterface.OnClickListener() 
{
    @Override
    public void onClick(DialogInterface dialog, int which) 
    {
        switch (which)
        {
            case DialogInterface.BUTTON_POSITIVE:
            datasource.deleteDiaryEntry(delTitle, delDate, delTime);

            // IN CASE NEED TO DELETE ALL DB ENTRIES UNCOMMENT THIS 
            // (AND COMMENT THE ABOVE METHOD)
            //datasource.deleteAll();

            Intent intent = new Intent(DiarySchedule.this, DiarySchedule.class);
            startActivity(intent);
            break;

            case DialogInterface.BUTTON_NEGATIVE:
            // No action taken
            break;
        }
    }
};



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

}

private class OnItemClickListener implements OnClickListener
{           
    private int mPosition;

    OnItemClickListener(int position)
    {
            mPosition = position;
    }

    @Override
    public void onClick(View v) 
    {
        Log.v(TAG, "onItemClick at position" + mPosition); 
        final String title = (String) ((TextView) findViewById(R.id.scheduleListTitle)).getText();
        System.out.println("Title is: " + title);
        String date = (String) ((TextView) findViewById(R.id.scheduleListDate)).getText();
        date = GetInfoConvertToDate(date);
        System.out.println("Date is: " + date);
        final String time = (String) ((TextView) findViewById(R.id.scheduleListTime)).getText();
        System.out.println("Time is: " + time);

        Intent descIntent = new Intent(DiarySchedule.this, DiaryDetailed.class);

        descIntent.putExtra("title", title);
        descIntent.putExtra("date", date);
        descIntent.putExtra("time", time);

        startActivity(descIntent);
    }               
}

}

当调试它到达OnItemClickListener OnClick方法时，正确地执行它但只是没有获取值为空的值。有任何想法吗？感谢

Answer 1

你的事情太过于复杂了

在您的主DiarySchedule活动中，您应该实现OnItemClickListener。覆盖侦听器的onItemClick方法并在其中执行操作。通过调用getListView（）来设置监听器.setOnItemClickListener（this）;在你的onCreate方法..

实施例。

public class DiarySchedule extends ListActivity implements OnItemClickListener
{

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

    datasource = new DiaryDataSource(this);
    datasource.open();

    List<DiaryEntry> values = datasource.getAllDiaryEntries();

    DiaryScheduleAdapter adapter = new DiaryScheduleAdapter(this,values);
    setListAdapter(adapter);

    registerForContextMenu(getListView());

    getListView().setOnItemClickListener(this); //this sets the listener


   }
   @Override
   public void onItemClick(AdapterView<?> arg0, View v, int position, long arg3)
   {

      String title = ((TextView)v.findViewById(R.id.scheduleListTitle)).getText().toString();
      String date = ((TextView)v.findViewById(R.id.scheduleListDate)).getText().toString();
      date = GetInfoConvertToDate(date);
      String time = ((TextView)v.findViewById(R.id.scheduleListTime)).getText().toString();


      Intent descIntent = new Intent(DiarySchedule.this, DiaryDetailed.class);
      descIntent.putExtra("title", title);
      descIntent.putExtra("date", date);
      descIntent.putExtra("time", time);

      startActivity(descIntent);

   }

}

然后，您可以删除对v.setOnClickListener的调用（new OnItemClickListener（position））;在您的适配器和您为处理点击而创建的类。

当在onItemClick方法中并且您尝试使用“findViewById”时，您应该使用“v.findViewById（id）;”因为您在视图“v”中搜索。

这可能是你的问题。（并且您可以这样修复它）但我建议按照我上面描述的“正确”方式进行操作，而不是为列表视图中的每个项目设置单独的处理程序

Answer 2

您有多个具有相同ID的视图（每行一个）。获取值时尝试替换

final String title = (String) ((TextView) findViewById(R.id.scheduleListTitle)).getText();

与

final String title = (String) ((TextView) v.findViewById(R.id.scheduleListTitle)).getText();

您尝试检索的其他值也是如此。

使用OnItemClickListener从List项中检索空值

2 个答案: