Create ForecastAdapter

ForecastAdapter.java

package com.example.android.sunshine.app;
 
import android.content.Context;
import android.database.Cursor;
import android.support.v4.widget.CursorAdapter;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.TextView;
import android.widget.ImageView;
 
/**
 * {@link ForecastAdapter} exposes a list of weather forecasts
 * from a {@link Cursor} to a {@link ListView}.
 */
public class ForecastAdapter extends CursorAdapter {
    public ForecastAdapter(Context context, Cursor c, int flags) {
        super(context, c, flags);
    }
 
    @Override
    public View newView(Context context, Cursor cursor, ViewGroup parent) {
        return LayoutInflater.from(context).inflate(R.layout.list_item_forecast, parent, false);
    }
 
    @Override
    public void bindView(View view, Context context, Cursor cursor) {
 
        // Read weather icon ID from cursor
        int weatherId = cursor.getInt(ForecastFragment.COL_WEATHER_ID);
        // Use placeholder image for now
        ImageView iconView = (ImageView) view.findViewById(R.id.list_item_icon);
        iconView.setImageResource(R.drawable.ic_launcher);
 
        // Read date from cursor
        String dateString = cursor.getString(ForecastFragment.COL_WEATHER_DATE);
        // Find TextView and set formatted date on it
        TextView dateView = (TextView) view.findViewById(R.id.list_item_date_textview);
        dateView.setText(Utility.getFriendlyDayString(context, dateString));
 
        // Read weather forecast from cursor
        String description = cursor.getString(ForecastFragment.COL_WEATHER_DESC);
        // Find TextView and set weather forecast on it
        TextView descriptionView = (TextView) view.findViewById(R.id.list_item_forecast_textview);
        descriptionView.setText(description);
 
        // Read user preference for metric or imperial temperature units
        boolean isMetric = Utility.isMetric(context);
 
        // Read high temperature from cursor
        float high = cursor.getFloat(ForecastFragment.COL_WEATHER_MAX_TEMP);
        // TODO: Find TextView and set formatted high temperature on it
 
        // Read low temperature from cursor
        float low = cursor.getFloat(ForecastFragment.COL_WEATHER_MIN_TEMP);
        // TODO: Find TextView and set formatted low temperature on it
    }
}

Helper methods for Utility.java

/** Required imports **/
 
import com.example.android.sunshine.app.data.WeatherContract;
import java.text.ParseException;
import java.text.SimpleDateFormat;
import java.util.Calendar;
import java.util.Date;
 

// Format used for storing dates in the database.  ALso used for converting those strings
// back into date objects for comparison/processing.
public static final String DATE_FORMAT = "yyyyMMdd";

/**
 * Helper method to convert the database representation of the date into something to display
 * to users.  As classy and polished a user experience as "20140102" is, we can do better.
 *
 * @param context Context to use for resource localization
 * @param dateStr The db formatted date string, expected to be of the form specified
 *                in Utility.DATE_FORMAT
 * @return a user-friendly representation of the date.
 */
public static String getFriendlyDayString(Context context, String dateStr) {
    // The day string for forecast uses the following logic:
    // For today: "Today, June 8"
    // For tomorrow:  "Tomorrow"
    // For the next 5 days: "Wednesday" (just the day name)
    // For all days after that: "Mon Jun 8"
 
    Date todayDate = new Date();
    String todayStr = WeatherContract.getDbDateString(todayDate);
    Date inputDate = WeatherContract.getDateFromDb(dateStr);
 
    // If the date we're building the String for is today's date, the format
    // is "Today, June 24"
    if (todayStr.equals(dateStr)) {
        String today = context.getString(R.string.today);
        return context.getString(
                R.string.format_full_friendly_date,
                today,
                getFormattedMonthDay(context, dateStr));
    } else {
        Calendar cal = Calendar.getInstance();
        cal.setTime(todayDate);
        cal.add(Calendar.DATE, 7);
        String weekFutureString = WeatherContract.getDbDateString(cal.getTime());
 
        if (dateStr.compareTo(weekFutureString) < 0) {
            // If the input date is less than a week in the future, just return the day name.
            return getDayName(context, dateStr);
        } else {
            // Otherwise, use the form "Mon Jun 3"
            SimpleDateFormat shortenedDateFormat = new SimpleDateFormat("EEE MMM dd");
            return shortenedDateFormat.format(inputDate);
        }
    }
}
 
/**
 * Given a day, returns just the name to use for that day.
 * E.g "today", "tomorrow", "wednesday".
 *
 * @param context Context to use for resource localization
 * @param dateStr The db formatted date string, expected to be of the form specified
 *                in Utility.DATE_FORMAT
 * @return
 */
public static String getDayName(Context context, String dateStr) {
    SimpleDateFormat dbDateFormat = new SimpleDateFormat(Utility.DATE_FORMAT);
    try {
        Date inputDate = dbDateFormat.parse(dateStr);
        Date todayDate = new Date();
        // If the date is today, return the localized version of "Today" instead of the actual
        // day name.
        if (WeatherContract.getDbDateString(todayDate).equals(dateStr)) {
            return context.getString(R.string.today);
        } else {
            // If the date is set for tomorrow, the format is "Tomorrow".
            Calendar cal = Calendar.getInstance();
            cal.setTime(todayDate);
            cal.add(Calendar.DATE, 1);
            Date tomorrowDate = cal.getTime();
            if (WeatherContract.getDbDateString(tomorrowDate).equals(
                    dateStr)) {
                return context.getString(R.string.tomorrow);
            } else {
                // Otherwise, the format is just the day of the week (e.g "Wednesday".
                SimpleDateFormat dayFormat = new SimpleDateFormat("EEEE");
                return dayFormat.format(inputDate);
            }
        }
    } catch (ParseException e) {
        e.printStackTrace();
        // It couldn't process the date correctly.
        return "";
    }
}
 
/**
 * Converts db date format to the format "Month day", e.g "June 24".
 * @param context Context to use for resource localization
 * @param dateStr The db formatted date string, expected to be of the form specified
 *                in Utility.DATE_FORMAT
 * @return The day in the form of a string formatted "December 6"
 */
public static String getFormattedMonthDay(Context context, String dateStr) {
    SimpleDateFormat dbDateFormat = new SimpleDateFormat(Utility.DATE_FORMAT);
    try {
        Date inputDate = dbDateFormat.parse(dateStr);
        SimpleDateFormat monthDayFormat = new SimpleDateFormat("MMMM dd");
        String monthDayString = monthDayFormat.format(inputDate);
        return monthDayString;
    } catch (ParseException e) {
        e.printStackTrace();
        return null;
    }
}
 
/**
 * Returns true if metric unit should be used, or false if
 * imperial units should be used.
 */
public static boolean isMetric(Context context) {
    SharedPreferences prefs = PreferenceManager.getDefaultSharedPreferences(context);
    return prefs.getString(context.getString(R.string.pref_units_key), 
            context.getString(R.string.pref_units_metric)).equals(
            context.getString(R.string.pref_units_metric));
}

Strings for strings.xml

<!-- Remember to set the root element of strings.xml to be <resources xmlns:xliff="http://schemas.android.com/apk/res-auto"> so it recognizes the xliff tags -->

<!-- Date label when displaying today's weather forecast [CHAR LIMIT=20] -->
<string name="today">Today</string>
 
<!-- Date label when displaying tomorrow's weather forecast [CHAR LIMIT=20] -->
<string name="tomorrow">Tomorrow</string>
 
<!-- Date format for displaying day of week and date (i.e. Mon Jun 1) [CHAR LIMIT=20] -->
<string name="format_full_friendly_date">
    <xliff:g id="day_of_week">%1$s</xliff:g>, <xliff:g id="date">%2$s</xliff:g>
</string>