Thursday 15 November 2012

Android Calendar Sample

This can be used for creating calendar in android 2.2 versions.


CalendarView.java


public class CalendarView extends Activity {

public Calendar 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

public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.calendar);

month = Calendar.getInstance();
itemmonth = (Calendar) month.clone();

items = new ArrayList<String>();
adapter = new CalendarAdapter(this, month);

GridView gridview = (GridView) findViewById(R.id.gridview);
gridview.setAdapter(adapter);

handler = new Handler();
handler.post(calendarUpdater);

TextView title = (TextView) findViewById(R.id.title);
title.setText(android.text.format.DateFormat.format("MMMM yyyy", month));

RelativeLayout previous = (RelativeLayout) findViewById(R.id.previous);

previous.setOnClickListener(new OnClickListener() {

@Override
public void onClick(View v) {
setPreviousMonth();
refreshCalendar();
}
});

RelativeLayout next = (RelativeLayout) 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);

}
});
}

protected void setNextMonth() {
if (month.get(Calendar.MONTH) == month.getActualMaximum(Calendar.MONTH)) {
month.set((month.get(Calendar.YEAR) + 1),
month.getActualMinimum(Calendar.MONTH), 1);
} else {
month.set(Calendar.MONTH, month.get(Calendar.MONTH) + 1);
}

}

protected void setPreviousMonth() {
if (month.get(Calendar.MONTH) == month.getActualMinimum(Calendar.MONTH)) {
month.set((month.get(Calendar.YEAR) - 1),
month.getActualMaximum(Calendar.MONTH), 1);
} else {
month.set(Calendar.MONTH, month.get(Calendar.MONTH) - 1);
}

}

protected void showToast(String string) {
Toast.makeText(this, string, Toast.LENGTH_SHORT).show();

}

public void refreshCalendar() {
TextView title = (TextView) 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() {

@Override
public void run() {
items.clear();

// Print dates of the current week
DateFormat df = new SimpleDateFormat("yyyy-MM-dd");
String itemvalue;
for (int i = 0; i < 7; i++) {
itemvalue = df.format(itemmonth.getTime());
itemmonth.add(Calendar.DATE, 1);
items.add("2012-09-12");
items.add("2012-10-07");
items.add("2012-10-15");
items.add("2012-10-20");
items.add("2012-11-30");
items.add("2012-11-28");
}

adapter.setItems(items);
adapter.notifyDataSetChanged();
}
};
}


CalendarAdapter.java




public class CalendarAdapter extends BaseAdapter {
private Context mContext;

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;

public CalendarAdapter(Context c, GregorianCalendar monthCalendar) {
CalendarAdapter.dayString = new ArrayList<String>();
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) {
for (int i = 0; i != items.size(); i++) {
if (items.get(i).length() == 1) {
items.set(i, "0" + items.get(i));
}
}
this.items = items;
}

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;
}

// show icon if date is not empty and it exists in the items array
ImageView iw = (ImageView) v.findViewById(R.id.date_icon);
if (date.length() > 0 && items != null && items.contains(date)) {
iw.setVisibility(View.VISIBLE);
} else {
iw.setVisibility(View.INVISIBLE);
}
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
items.clear();
dayString.clear();
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;
}

}


calendar.xml




<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    android:background="@drawable/background"
    android:orientation="vertical" >

    <RelativeLayout
        android:id="@+id/header"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:background="@drawable/calendar_top" >

        <RelativeLayout
            android:id="@+id/previous"
            android:layout_width="40dip"
            android:layout_height="30dip"
            android:layout_alignParentLeft="true" >

            <ImageView
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:layout_centerInParent="true"
                android:background="@drawable/arrow_left" />
        </RelativeLayout>

        <TextView
            android:id="@+id/title"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_centerHorizontal="true"
            android:layout_marginTop="5dip"
            android:textColor="#000000"
            android:textSize="18dip"
            android:textStyle="bold" />

        <RelativeLayout
            android:id="@+id/next"
            android:layout_width="40dip"
            android:layout_height="30dip"
            android:layout_alignParentRight="true" >

            <ImageView
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:layout_centerInParent="true"
                android:background="@drawable/arrow_right" />
        </RelativeLayout>
    </RelativeLayout>

    <GridView
        xmlns:android="http://schemas.android.com/apk/res/android"
        android:id="@+id/gridview"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:layout_gravity="center_horizontal"
        android:listSelector="@android:color/transparent"
        android:numColumns="7"
        android:stretchMode="columnWidth" />

</LinearLayout>


calendar_item.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:background="@drawable/calendar_cell"
    android:gravity="center"
    android:orientation="vertical"
    android:padding="2dip" >

    <TextView
        xmlns:android="http://schemas.android.com/apk/res/android"
        android:id="@+id/date"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:textColor="#0000D7"
        android:textSize="14dip"
        android:textStyle="bold" >
    </TextView>

    <ImageView
        xmlns:android="http://schemas.android.com/apk/res/android"
        android:id="@+id/date_icon"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:src="@drawable/dot"
        android:visibility="gone" />

</LinearLayout>