以日期为 SectionHeader 的自定义 ListView(使用自定义 SimpleCursorAdapter) [英] Custom ListView with Date as SectionHeader (Used custom SimpleCursorAdapter)
本文介绍了以日期为 SectionHeader 的自定义 ListView(使用自定义 SimpleCursorAdapter)的处理方法，对大家解决问题具有一定的参考价值，需要的朋友们下面随着小编来一起学习吧！
问题描述
我想以日期作为 SectionHeader 显示 ListView.
I want to display ListView with Date as SectionHeader.
我有什么:我正在使用自定义 SimpleCursorAdapter 从 sqlite 数据库显示 ListView.
What i have : I am displaying ListView from sqlite database using custom SimpleCursorAdapter.
我的自定义 SimpleCursorAdapter 是:
My Custom SimpleCursorAdapter is :
public class DomainAdapter extends SimpleCursorAdapter{
private Cursor dataCursor;
private LayoutInflater mInflater;
public DomainAdapter(Context context, int layout, Cursor dataCursor, String[] from,
int[] to) {
super(context, layout, dataCursor, from, to);
this.dataCursor = dataCursor;
mInflater = LayoutInflater.from(context);
}
public View getView(int position, View convertView, ViewGroup parent) {
ViewHolder holder;
if (convertView == null) {
convertView = mInflater.inflate(R.layout.todo_row, null);
holder = new ViewHolder();
holder.text1 = (TextView) convertView.findViewById(R.id.label);//Task Title
holder.text2 = (TextView) convertView.findViewById(R.id.label2);//Task Date
holder.img = (ImageView) convertView.findViewById(R.id.task_icon);
convertView.setTag(holder);
} else {
holder = (ViewHolder) convertView.getTag();
}
dataCursor.moveToPosition(position);
int title = dataCursor.getColumnIndex("title");
String task_title = dataCursor.getString(title);
int title_date = dataCursor.getColumnIndex("day");
String task_day = dataCursor.getString(title_date);
int description_index = dataCursor.getColumnIndex("priority");
int priority = dataCursor.getInt(description_index);
holder.text1.setText(task_title);
holder.text2.setText(task_day);
if(priority==1) holder.img.setImageResource(R.drawable.redbutton);
else if(priority==2) holder.img.setImageResource(R.drawable.bluebutton);
else if(priority==3)holder.img.setImageResource(R.drawable.greenbutton);
else holder.img.setImageResource(R.drawable.redbuttonchecked);
return convertView;
}
static class ViewHolder {
TextView text1;
TextView text2;
ImageView img;
}
}
到目前为止的 Google 结果:
问题:我想以日期作为部分标题显示列表视图.当然日期值来自sqlite数据库.
Problem : I want to display listview with Date as section headers. Ofcourse Date values come from sqlite database.
谁能指导我如何完成这项任务.
Can anyone please guide me how can i achieve this task.
或者给我提供一个示例代码或与之相关的确切(类似)代码.
Or Provide me a Sample Code or Exact(like) Code related to the same.
已编辑根据 Graham Borald 的回答(这很好用.但是这是一个快速修复.)
Edited According to Graham Borald's Answer (This works fine. However it was a quick fix.)
public class DomainAdapter extends SimpleCursorAdapter{
private Cursor dataCursor;
private LayoutInflater mInflater;
public DomainAdapter(Context context, int layout, Cursor dataCursor, String[] from,
int[] to) {
super(context, layout, dataCursor, from, to);
this.dataCursor = dataCursor;
mInflater = LayoutInflater.from(context);
}
@Override
public View getView(int position, View convertView, ViewGroup parent) {
ViewHolder holder;
if (convertView == null)
{
convertView = mInflater.inflate(R.layout.tasks_row, null);
holder = new ViewHolder();
holder.text1 = (TextView) convertView.findViewById(R.id.label);//Task Title
holder.text2 = (TextView) convertView.findViewById(R.id.label2);//Task Date
holder.img = (ImageView) convertView.findViewById(R.id.taskImage);
holder.sec_hr=(TextView) convertView.findViewById(R.id.sec_header);
convertView.setTag(holder);
}
else
{
holder = (ViewHolder) convertView.getTag();
}
dataCursor.moveToPosition(position);
int title = dataCursor.getColumnIndex("title");
String task_title = dataCursor.getString(title);
int title_date = dataCursor.getColumnIndex("due_date");
String task_day = dataCursor.getString(title_date);
int description_index = dataCursor.getColumnIndex("priority");
int priority = dataCursor.getInt(description_index);
String prevDate = null;
if (dataCursor.getPosition() > 0 && dataCursor.moveToPrevious()) {
prevDate = dataCursor.getString(title_date);
dataCursor.moveToNext();
}
if(task_day.equals(prevDate))
{
holder.sec_hr.setVisibility(View.GONE);
}
else
{
holder.sec_hr.setText(task_day);
holder.sec_hr.setVisibility(View.VISIBLE);
}
holder.text1.setText(task_title);
holder.text2.setText(task_day);
if(priority==1) holder.img.setImageResource(R.drawable.redbutton);
else if(priority==2) holder.img.setImageResource(R.drawable.bluebutton);
else if(priority==3)holder.img.setImageResource(R.drawable.greenbutton);
else holder.img.setImageResource(R.drawable.redbuttonchecked);
return convertView;
}
static class ViewHolder {
TextView text1;
TextView text2;
TextView sec_hr;
ImageView img;
}
}
编辑根据CommonsWare的回答
Edited According to CommonsWare's Answer
public class DomainAdapter extends SimpleCursorAdapter{
private Cursor dataCursor;
private TodoDbAdapter adapter;
private LayoutInflater mInflater;
boolean header;
String last_day;
public DomainAdapter(Context context, int layout, Cursor dataCursor, String[] from,
int[] to) {
super(context, layout, dataCursor, from, to);
this.dataCursor = dataCursor;
mInflater = LayoutInflater.from(context);
header=true;
adapter=new TodoDbAdapter(context);
}
@Override
public View getView(int position, View convertView, ViewGroup parent) {
ViewHolder holder = null;
TitleHolder title_holder = null;
if(getItemViewType(position)==1)
{
//convertView= mInflater.inflate(R.layout.todo_row, parent, false);
if (convertView == null)
{
convertView = mInflater.inflate(R.layout.todo_row, null);
holder = new ViewHolder();
holder.text1 = (TextView) convertView.findViewById(R.id.label);//Task Title
holder.text2 = (TextView) convertView.findViewById(R.id.label2);//Task Date
holder.img = (ImageView) convertView.findViewById(R.id.task_icon);
convertView.setTag(holder);
}
else
{
holder = (ViewHolder) convertView.getTag();
}
dataCursor.moveToPosition(position);
int title = dataCursor.getColumnIndex("title");
String task_title = dataCursor.getString(title);
int title_date = dataCursor.getColumnIndex("day");
String task_day = dataCursor.getString(title_date);
int description_index = dataCursor.getColumnIndex("priority");
int priority = dataCursor.getInt(description_index);
holder.text1.setText(task_title);
holder.text2.setText(task_day);
if(priority==1) holder.img.setImageResource(R.drawable.redbutton);
else if(priority==2) holder.img.setImageResource(R.drawable.bluebutton);
else if(priority==3)holder.img.setImageResource(R.drawable.greenbutton);
else holder.img.setImageResource(R.drawable.redbuttonchecked);
}
else
{
if (convertView == null)
{
convertView = mInflater.inflate(R.layout.section_header, null);
title_holder = new TitleHolder();
title_holder.datee = (TextView) convertView.findViewById(R.id.sec_header);//Task Title
convertView.setTag(title_holder);
}
else
{
title_holder = (TitleHolder) convertView.getTag();
}
dataCursor.moveToPosition(position);
int title_date = dataCursor.getColumnIndex("day");
String task_day = dataCursor.getString(title_date);
title_holder.datee.setText(task_day);
}
return convertView;
}
static class ViewHolder {
TextView text1;
TextView text2;
ImageView img;
}
static class TitleHolder{
TextView datee;
}
@Override
public int getCount() {
return dataCursor.getCount()+1; //just for testing i took no. of headers=1
}
@Override
public int getViewTypeCount() {
return 2;
}
@Override
public int getItemViewType(int position) {
dataCursor.moveToPosition(position);
**Long id=dataCursor.getLong(position);**
Cursor date=adapter.fetchTodo(id);
int title_date = date.getColumnIndex("day");
String task_day = date.getString(title_date);
Log.i("tag",task_day);
if(last_day.equals(task_day))
return 1;//Display Actual Row
else
{
last_day=task_day;//Displaying Header
return 0;
}
}
/*
@Override
public View newView(Context context, Cursor cursor, ViewGroup parent) {
final View view;
if(getItemViewType(cursor.getPosition())==1)
view= mInflater.inflate(R.layout.todo_row, parent, false);
else
view=mInflater.inflate(R.layout.section_header,parent, false);
return view;
}
@Override
public void bindView(View convertView, Context context, Cursor cursor) {
long id = cursor.getPosition();
}*/
}
我在以下行收到 Null Pointer Exception:Cursor date=adapter.fetchTodo(id);好像 Cursor 没有得到任何数据.
I am getting Null Pointer Exception at line : Cursor date=adapter.fetchTodo(id);
Seems that Cursor is not getting any data.
推荐答案
到目前为止，最简单的方法是在每个项目中嵌入日期标题视图.然后，您需要在 bindView 中做的就是将前一行的日期与本行的日期进行比较，如果相同则隐藏该日期.像这样:
By far the simplest way to do this is to embed the date header view in every item. Then, all you need to do in bindView is compare the previous row's date to this row's date, and hide the date if it's the same. Something like this:
String thisDate = cursor.getString(dateIndex);
String prevDate = null;
// get previous item's date, for comparison
if (cursor.getPosition() > 0 && cursor.moveToPrevious()) {
prevDate = cursor.getString(dateIndex);
cursor.moveToNext();
}
// enable section heading if it's the first one, or
// different from the previous one
if (prevDate == null || !prevDate.equals(thisDate)) {
dateSectionHeaderView.setVisibility(View.VISIBLE);
} else {
dateSectionHeaderView.setVisibility(View.GONE);
}
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