Java tutorial
/* * Copyright (C) 2014 The Android Open Source Project * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ package ua.com.elius.sunshine.app; import android.content.Context; import android.content.Intent; import android.database.Cursor; import android.net.Uri; import android.os.Bundle; import android.support.v4.app.Fragment; import android.support.v4.app.LoaderManager; import android.support.v4.content.CursorLoader; import android.support.v4.content.Loader; import android.util.Log; import android.view.LayoutInflater; import android.view.Menu; import android.view.MenuInflater; import android.view.MenuItem; import android.view.View; import android.view.ViewGroup; import android.widget.AdapterView; import android.widget.ListView; import ua.com.elius.sunshine.app.data.WeatherContract; import ua.com.elius.sunshine.app.sync.SunshineSyncAdapter; /** * Encapsulates fetching the forecast and displaying it as a {@link ListView} layout. */ public class ForecastFragment extends Fragment implements LoaderManager.LoaderCallbacks<Cursor> { private static final String LOG_TAG = ForecastFragment.class.getSimpleName(); private static final int FORECAST_LOADER = 0; private static final String SELECTED_KEY = "position"; public static final String LOCATION_KEY = "location"; private static final String[] FORECAST_COLUMNS = { // In this case the id needs to be fully qualified with a table name, since // the content provider joins the location & weather tables in the background // (both have an _id column) // On the one hand, that's annoying. On the other, you can search the weather table // using the location set by the user, which is only in the Location table. // So the convenience is worth it. WeatherContract.WeatherEntry.TABLE_NAME + "." + WeatherContract.WeatherEntry._ID, WeatherContract.WeatherEntry.COLUMN_DATE, WeatherContract.WeatherEntry.COLUMN_SHORT_DESC, WeatherContract.WeatherEntry.COLUMN_MAX_TEMP, WeatherContract.WeatherEntry.COLUMN_MIN_TEMP, WeatherContract.LocationEntry.COLUMN_LOCATION_SETTING, WeatherContract.WeatherEntry.COLUMN_WEATHER_ID, WeatherContract.LocationEntry.COLUMN_COORD_LAT, WeatherContract.LocationEntry.COLUMN_COORD_LONG }; // These indices are tied to FORECAST_COLUMNS. If FORECAST_COLUMNS changes, these // must change. static final int COL_WEATHER_ID = 0; static final int COL_WEATHER_DATE = 1; static final int COL_WEATHER_DESC = 2; static final int COL_WEATHER_MAX_TEMP = 3; static final int COL_WEATHER_MIN_TEMP = 4; static final int COL_LOCATION_SETTING = 5; static final int COL_WEATHER_CONDITION_ID = 6; static final int COL_COORD_LAT = 7; static final int COL_COORD_LONG = 8; private ForecastAdapter mForecastAdapter; private int mPosition; private ListView mListView; private boolean mUseTodayLayout; public ForecastFragment() { } public void setUseTodayLayout(boolean useTodayLayout) { mUseTodayLayout = useTodayLayout; if (mForecastAdapter != null) { mForecastAdapter.setUseTodayLayout(mUseTodayLayout); } } @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); // Add this line in order for this fragment to handle menu events. setHasOptionsMenu(true); } @Override public void onCreateOptionsMenu(Menu menu, MenuInflater inflater) { inflater.inflate(R.menu.forecast_fragment, menu); } @Override public boolean onOptionsItemSelected(MenuItem item) { // Handle action bar item clicks here. The action bar will // automatically handle clicks on the Home/Up button, so long // as you specify a parent activity in AndroidManifest.xml. int id = item.getItemId(); if (id == R.id.action_refresh) { updateWeather(); return true; } if (id == R.id.action_view_location) { openPreferredLocationInMap(); } return super.onOptionsItemSelected(item); } @Override public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) { if (savedInstanceState != null && savedInstanceState.containsKey(SELECTED_KEY)) { mPosition = savedInstanceState.getInt(SELECTED_KEY); } // The CursorAdapter will take data from our cursor and populate the ListView. mForecastAdapter = new ForecastAdapter(getActivity(), null, 0); View rootView = inflater.inflate(R.layout.fragment_main, container, false); // Get a reference to the ListView, and attach this adapter to it. mListView = (ListView) rootView.findViewById(R.id.listview_forecast); mListView.setAdapter(mForecastAdapter); mListView.setOnItemClickListener(new AdapterView.OnItemClickListener() { @Override public void onItemClick(AdapterView adapterView, View view, int position, long l) { // CursorAdapter returns a cursor at the correct position for getItem(), or null // if it cannot seek to that position. Cursor cursor = (Cursor) adapterView.getItemAtPosition(position); if (cursor != null) { String locationSetting = Utility.getPreferredLocation(getActivity()); Callback cb; try { cb = (Callback) getActivity(); Uri dateUri = WeatherContract.WeatherEntry.buildWeatherLocationWithDate(locationSetting, cursor.getLong(COL_WEATHER_DATE)); cb.onItemSelected(dateUri); } catch (ClassCastException e) { Log.e(LOG_TAG, "Activity does not implement required callback"); } mPosition = position; } } }); return rootView; } @Override public void onSaveInstanceState(Bundle outState) { super.onSaveInstanceState(outState); if (mPosition != ListView.INVALID_POSITION) { outState.putInt(SELECTED_KEY, mPosition); } } @Override public void onActivityCreated(Bundle savedInstanceState) { getLoaderManager().initLoader(FORECAST_LOADER, null, this); super.onActivityCreated(savedInstanceState); } private void updateWeather() { Context context = getActivity(); // String location = Utility.getPreferredLocation(context); // // AlarmManager alarmMgr; // PendingIntent alarmIntent; // // alarmIntent = PendingIntent.getBroadcast(context, // 0, // new Intent(context, SunshineService.AlarmReceiver.class) // .putExtra(ForecastFragment.LOCATION_KEY, location), // PendingIntent.FLAG_ONE_SHOT // ); // // alarmMgr = (AlarmManager)context.getSystemService(Context.ALARM_SERVICE); // alarmMgr.set(AlarmManager.RTC_WAKEUP, System.currentTimeMillis() + 5000, alarmIntent); SunshineSyncAdapter.syncImmediately(context); } @Override public void onStart() { super.onStart(); // updateWeather(); } @Override public Loader<Cursor> onCreateLoader(int i, Bundle bundle) { String locationSetting = Utility.getPreferredLocation(getActivity()); // Sort order: Ascending, by date. String sortOrder = WeatherContract.WeatherEntry.COLUMN_DATE + " ASC"; Uri weatherForLocationUri = WeatherContract.WeatherEntry.buildWeatherLocationWithStartDate(locationSetting, System.currentTimeMillis()); return new CursorLoader(getActivity(), weatherForLocationUri, FORECAST_COLUMNS, null, null, sortOrder); } @Override public void onLoadFinished(Loader<Cursor> cursorLoader, Cursor cursor) { mForecastAdapter.swapCursor(cursor); if (mPosition != ListView.INVALID_POSITION) { mListView.smoothScrollToPosition(mPosition); } } @Override public void onLoaderReset(Loader<Cursor> cursorLoader) { mForecastAdapter.swapCursor(null); } public void onLocationChanged() { updateWeather(); getLoaderManager().restartLoader(FORECAST_LOADER, null, this); } /** * A callback interface that all activities containing this fragment must * implement. This mechanism allows activities to be notified of item * selections. */ public interface Callback { /** * DetailFragmentCallback for when an item has been selected. */ public void onItemSelected(Uri contentURI); } private void openPreferredLocationInMap() { if (mForecastAdapter != null) { Cursor c = mForecastAdapter.getCursor(); if (c != null) { c.moveToPosition(0); String latitude; String longitude; latitude = c.getString(COL_COORD_LAT); longitude = c.getString(COL_COORD_LONG); Uri geoLocation = Uri.parse("geo:" + latitude + "," + longitude); Log.d(LOG_TAG, geoLocation.toString()); Intent viewLocationIntent; viewLocationIntent = new Intent(); viewLocationIntent.setAction(Intent.ACTION_VIEW); viewLocationIntent.setData(geoLocation); if (viewLocationIntent.resolveActivity(getActivity().getPackageManager()) != null) { startActivity(viewLocationIntent); } } } } }