所以我根据我找到的教程创建了一个日历。它一直有效，直到我尝试自定义它。
我想要做的是将光标信息存储为 private ArrayList<HashMap<String, String>> list;然后将其传递给日历 fragment ，以便在那里显示/隐藏该日期的图像。然而我在这方面遇到了严重的失败:
for (HashMap<String, String> map : list)
for (Entry<String, String> mapEntry : map.entrySet()){
String key = mapEntry.getKey();
String value = mapEntry.getValue();
Log.i("PROJECTCARUSO", "key: "+ key + " value:" + value);
}
当然，我并不是想在此处显示或隐藏，而是只是迭代我的 map 。有人可以帮忙吗？
public class CalendarFragment extends Fragment {
public GregorianCalendar month, itemmonth;// calendar instances.
public CalendarAdapter adapter; // adapter instance
public Handler handler; // for grabbing some event values for showing the dot
// marker.
public ArrayList<String> items; // container to store calendar items which
// needs showing the event marker
static final ArrayList<HashMap<String,String>> list = new ArrayList<HashMap<String,String>>();
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
}
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
View view = inflater.inflate(R.layout.fragment_calendar, null);
Locale.setDefault( Locale.US );
month = (GregorianCalendar) GregorianCalendar.getInstance();
itemmonth = (GregorianCalendar) month.clone();
items = new ArrayList<String>();
adapter = new CalendarAdapter(getActivity(), month);
GridView gridview = (GridView) view.findViewById(R.id.gridview);
gridview.setAdapter(adapter);
handler = new Handler();
handler.post(calendarUpdater);
TextView title = (TextView) view.findViewById(R.id.title);
title.setText(android.text.format.DateFormat.format("MMMM yyyy", month));
RelativeLayout previous = (RelativeLayout) view.findViewById(R.id.previous);
previous.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View v) {
setPreviousMonth();
refreshCalendar();
}
});
RelativeLayout next = (RelativeLayout) view.findViewById(R.id.next);
next.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View v) {
setNextMonth();
refreshCalendar();
}
});
gridview.setOnItemClickListener(new OnItemClickListener() {
public void onItemClick(AdapterView<?> parent, View v,
int position, long id) {
((CalendarAdapter) parent.getAdapter()).setSelected(v);
String selectedGridDate = CalendarAdapter.dayString
.get(position);
String[] separatedTime = selectedGridDate.split("-");
String gridvalueString = separatedTime[2].replaceFirst("^0*",
"");// taking last part of date. ie; 2 from 2012-12-02.
int gridvalue = Integer.parseInt(gridvalueString);
// navigate to next or previous month on clicking offdays.
if ((gridvalue > 10) && (position < 8)) {
setPreviousMonth();
refreshCalendar();
} else if ((gridvalue < 7) && (position > 28)) {
setNextMonth();
refreshCalendar();
}
((CalendarAdapter) parent.getAdapter()).setSelected(v);
showToast(selectedGridDate);
}
});
return view;
}
protected void setNextMonth() {
if (month.get(GregorianCalendar.MONTH) == month
.getActualMaximum(GregorianCalendar.MONTH)) {
month.set((month.get(GregorianCalendar.YEAR) + 1),
month.getActualMinimum(GregorianCalendar.MONTH), 1);
} else {
month.set(GregorianCalendar.MONTH,
month.get(GregorianCalendar.MONTH) + 1);
}
}
protected void setPreviousMonth() {
if (month.get(GregorianCalendar.MONTH) == month
.getActualMinimum(GregorianCalendar.MONTH)) {
month.set((month.get(GregorianCalendar.YEAR) - 1),
month.getActualMaximum(GregorianCalendar.MONTH), 1);
} else {
month.set(GregorianCalendar.MONTH,
month.get(GregorianCalendar.MONTH) - 1);
}
}
protected void showToast(String string) {
Toast.makeText(getActivity(), string, Toast.LENGTH_SHORT).show();
}
public void refreshCalendar() {
TextView title = (TextView) getActivity().findViewById(R.id.title);
adapter.refreshDays();
adapter.notifyDataSetChanged();
handler.post(calendarUpdater); // generate some calendar items
title.setText(android.text.format.DateFormat.format("MMMM yyyy", month));
}
public Runnable calendarUpdater = new Runnable() {
@SuppressWarnings("static-access")
@Override
public void run() {
items.clear();
// Print dates of the current week
SimpleDateFormat df = new SimpleDateFormat("yyyy-MM-dd",Locale.US);
String itemvalue;
//start date for cursor
String startdate = df.format(month.getTime());
//end date
month.add(month.MONTH, 1);
String enddate = df.format(month.getTime());
month.add(month.MONTH, -1);
// Get the data
Cursor c = getActivity().getContentResolver().query(StatusProvider.CONTENT_URI_CHARTING, null, "? < " + StatusData.KEY_CHARTING_DATE + " AND ? > " + StatusData.KEY_CHARTING_DATE , new String[] {startdate, enddate}, null); //
getActivity().startManagingCursor(c);
c.moveToFirst();
//int i = 0;
if (c.getCount()>0 && c!=null) {
while (c.isAfterLast() == false)
{
itemvalue = df.format(itemmonth.getTime());
itemmonth.add(GregorianCalendar.DATE, 1);
items.add(c.getString(c.getColumnIndex(StatusData.KEY_CHARTING_DATE)));
c.moveToNext();
}
}
HashMap<String,String> temp = new HashMap<String,String>();
c.moveToFirst();
while(c.moveToNext()){
Log.i("PROJECTCARUSO", "Adding to HashMap");
temp.put(StatusData.KEY_CHARTING_DATE, c.getString(c.getColumnIndex(StatusData.KEY_CHARTING_DATE)));
temp.put(StatusData.KEY_CHARTING_PERIOD, c.getString(c.getColumnIndex(StatusData.KEY_CHARTING_PERIOD)));
temp.put(StatusData.KEY_CHARTING_INTERCORSE, c.getString(c.getColumnIndex(StatusData.KEY_CHARTING_INTERCORSE)));
temp.put(StatusData.KEY_CHARTING_MOOD, c.getString(c.getColumnIndex(StatusData.KEY_CHARTING_MOOD)));
temp.put(StatusData.KEY_CHARTING_HEADACHE, c.getString(c.getColumnIndex(StatusData.KEY_CHARTING_HEADACHE)));
temp.put(StatusData.KEY_CHARTING_TEST, c.getString(c.getColumnIndex(StatusData.KEY_CHARTING_TEST)));
temp.put(StatusData.KEY_CHARTING_ENERGY, c.getString(c.getColumnIndex(StatusData.KEY_CHARTING_ENERGY)));
list.add(temp);
}
adapter.setItems(items, list);
adapter.notifyDataSetChanged();
}
};
}
助手:
public class CalendarAdapter extends BaseAdapter {
private Context mContext;
ArrayList<Record> members = new ArrayList<Record>();
private java.util.Calendar month;
public GregorianCalendar pmonth; // calendar instance for previous month
/**
* calendar instance for previous month for getting complete view
*/
public GregorianCalendar pmonthmaxset;
private GregorianCalendar selectedDate;
int firstDay;
int maxWeeknumber;
int maxP;
int calMaxP;
int lastWeekDay;
int leftDays;
int mnthlength;
String itemvalue, curentDateString;
DateFormat df;
private ArrayList<String> items;
public static List<String> dayString;
private View previousView;
private ArrayList<HashMap<String, String>> list;
public CalendarAdapter(Context c, GregorianCalendar monthCalendar) {
CalendarAdapter.dayString = new ArrayList<String>();
Locale.setDefault( Locale.US );
month = monthCalendar;
selectedDate = (GregorianCalendar) monthCalendar.clone();
mContext = c;
month.set(GregorianCalendar.DAY_OF_MONTH, 1);
this.items = new ArrayList<String>();
df = new SimpleDateFormat("yyyy-MM-dd", Locale.US);
curentDateString = df.format(selectedDate.getTime());
refreshDays();
}
public void setItems(ArrayList<String> items, ArrayList<HashMap<String, String>> list) {
this.items = items;
this.list = list;
}
public int getCount() {
return dayString.size();
}
public Object getItem(int position) {
return dayString.get(position);
}
public long getItemId(int position) {
return 0;
}
// create a new view for each item referenced by the Adapter
public View getView(int position, View convertView, ViewGroup parent) {
View v = convertView;
TextView dayView;
if (convertView == null) { // if it's not recycled, initialize some
// attributes
LayoutInflater vi = (LayoutInflater) mContext
.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
v = vi.inflate(R.layout.calendar_item, null);
}
dayView = (TextView) v.findViewById(R.id.date);
// separates daystring into parts.
String[] separatedTime = dayString.get(position).split("-");
// taking last part of date. ie; 2 from 2012-12-02
String gridvalue = separatedTime[2].replaceFirst("^0*", "");
// checking whether the day is in current month or not.
if ((Integer.parseInt(gridvalue) > 1) && (position < firstDay)) {
// setting offdays to white color.
dayView.setTextColor(Color.WHITE);
dayView.setClickable(false);
dayView.setFocusable(false);
} else if ((Integer.parseInt(gridvalue) < 7) && (position > 28)) {
dayView.setTextColor(Color.WHITE);
dayView.setClickable(false);
dayView.setFocusable(false);
} else {
// setting curent month's days in blue color.
dayView.setTextColor(Color.BLUE);
}
if (dayString.get(position).equals(curentDateString)) {
setSelected(v);
previousView = v;
} else {
v.setBackgroundResource(R.drawable.list_item_background);
}
dayView.setText(gridvalue);
// create date string for comparison
String date = dayString.get(position);
if (date.length() == 1) {
date = "0" + date;
}
String monthStr = "" + (month.get(GregorianCalendar.MONTH) + 1);
if (monthStr.length() == 1) {
monthStr = "0" + monthStr;
}
for (HashMap<String, String> map : list)
for (Entry<String, String> mapEntry : map.entrySet()){
String key = mapEntry.getKey();
String value = mapEntry.getValue();
Log.i("PROJECTCARUSO", "key: "+ key + " value:" + value);
}
return v;
}
public View setSelected(View view) {
if (previousView != null) {
previousView.setBackgroundResource(R.drawable.list_item_background);
}
previousView = view;
view.setBackgroundResource(R.drawable.calendar_cel_selectl);
return view;
}
public void refreshDays() {
// clear items
list.clear();
dayString.clear();
Locale.setDefault( Locale.US );
pmonth = (GregorianCalendar) month.clone();
// month start day. ie; sun, mon, etc
firstDay = month.get(GregorianCalendar.DAY_OF_WEEK);
// finding number of weeks in current month.
maxWeeknumber = month.getActualMaximum(GregorianCalendar.WEEK_OF_MONTH);
// allocating maximum row number for the gridview.
mnthlength = maxWeeknumber * 7;
maxP = getMaxP(); // previous month maximum day 31,30....
calMaxP = maxP - (firstDay - 1);// calendar offday starting 24,25 ...
/**
* Calendar instance for getting a complete gridview including the three
* month's (previous,current,next) dates.
*/
pmonthmaxset = (GregorianCalendar) pmonth.clone();
/**
* setting the start date as previous month's required date.
*/
pmonthmaxset.set(GregorianCalendar.DAY_OF_MONTH, calMaxP + 1);
/**
* filling calendar gridview.
*/
for (int n = 0; n < mnthlength; n++) {
itemvalue = df.format(pmonthmaxset.getTime());
pmonthmaxset.add(GregorianCalendar.DATE, 1);
dayString.add(itemvalue);
}
}
private int getMaxP() {
int maxP;
if (month.get(GregorianCalendar.MONTH) == month
.getActualMinimum(GregorianCalendar.MONTH)) {
pmonth.set((month.get(GregorianCalendar.YEAR) - 1),
month.getActualMaximum(GregorianCalendar.MONTH), 1);
} else {
pmonth.set(GregorianCalendar.MONTH,
month.get(GregorianCalendar.MONTH) - 1);
}
maxP = pmonth.getActualMaximum(GregorianCalendar.DAY_OF_MONTH);
return maxP;
}
}
最佳答案
当您调用gridview.setAdapter(adapter);时和GridView已准备好显示它调用的元素 getView在您的适配器上。
那时list你的适配器里面是空的，你会得到一个 NullPointerException ，因为它发生在调用 setItems 之前.
“修复”它的最简单方法是初始化 list :
private ArrayList<HashMap<String, String>> list = new ArrayList<HashMap<String, String>>();
或者在循环之前检查 null:
if (list != null) {
for (HashMap<String, String> map : list) {
for (Entry<String, String> mapEntry : map.entrySet()){
String key = mapEntry.getKey();
String value = mapEntry.getValue();
Log.i("PROJECTCARUSO", "key: "+ key + " value:" + value);
}
}
}
关于java - 日历，传递 ArrayList<HashMap，并迭代它，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/17097751/