Java tutorial
/* * Firetweet - Twitter client for Android * * Copyright (C) 2012-2014 Mariotaku Lee <mariotaku.lee@gmail.com> * * This program is free software: you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation, either version 3 of the License, or * (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program. If not, see <http://www.gnu.org/licenses/>. */ package org.getlantern.firetweet.preference; import android.app.AlertDialog; import android.app.ProgressDialog; import android.content.Context; import android.content.DialogInterface; import android.content.DialogInterface.OnCancelListener; import android.content.DialogInterface.OnClickListener; import android.content.SharedPreferences; import android.os.AsyncTask; import android.preference.Preference; import android.util.AttributeSet; import android.view.View; import android.view.ViewGroup; import android.widget.ArrayAdapter; import android.widget.ListView; import android.widget.TextView; import org.getlantern.firetweet.Constants; import org.getlantern.firetweet.R; import java.text.Collator; import java.util.Comparator; import java.util.List; import twitter4j.Location; import twitter4j.ResponseList; import twitter4j.Twitter; import twitter4j.TwitterException; import static org.getlantern.firetweet.util.Utils.getDefaultTwitterInstance; public class TrendsLocationPreference extends Preference implements Constants, OnClickListener { private SharedPreferences mPreferences; private int mCheckedWoeId = 1; private GetAvailableTrendsTask mGetAvailableTrendsTask; private final AvailableTrendsAdapter mAdapter; private AlertDialog mDialog; public TrendsLocationPreference(final Context context) { this(context, null); } public TrendsLocationPreference(final Context context, final AttributeSet attrs) { this(context, attrs, android.R.attr.preferenceStyle); } public TrendsLocationPreference(final Context context, final AttributeSet attrs, final int defStyle) { super(context, attrs, defStyle); mAdapter = new AvailableTrendsAdapter(context); } @Override public void onClick(final DialogInterface dialog, final int which) { final SharedPreferences.Editor editor = getEditor(); if (editor == null) return; final Location item = mAdapter.getItem(which); if (item != null) { editor.putInt(KEY_LOCAL_TRENDS_WOEID, item.getWoeid()); editor.apply(); } if (mDialog != null && mDialog.isShowing()) { mDialog.dismiss(); } } @Override protected void onClick() { mPreferences = getSharedPreferences(); if (mPreferences == null) return; mCheckedWoeId = mPreferences.getInt(KEY_LOCAL_TRENDS_WOEID, 1); if (mGetAvailableTrendsTask != null) { mGetAvailableTrendsTask.cancel(false); } mGetAvailableTrendsTask = new GetAvailableTrendsTask(getContext()); mGetAvailableTrendsTask.execute(); } private static class AvailableTrendsAdapter extends ArrayAdapter<Location> { private final Context mContext; public AvailableTrendsAdapter(final Context context) { super(context, android.R.layout.simple_list_item_single_choice); mContext = context; } public int findItemPosition(final int woeid) { final int count = getCount(); for (int i = 0; i < count; i++) { final Location item = getItem(i); if (item.getWoeid() == woeid) return i; } return -1; } @Override public View getView(final int position, final View convertView, final ViewGroup parent) { final View view = super.getView(position, convertView, parent); final TextView text = (TextView) (view instanceof TextView ? view : view.findViewById(android.R.id.text1)); final Location item = getItem(position); if (item != null && text != null) { text.setSingleLine(); text.setText(item.getName()); } return view; } public void setData(final List<Location> data) { clear(); if (data != null) { addAll(data); } sort(new LocationComparator(mContext)); } } private static class LocationComparator implements Comparator<Location> { private final Collator mCollator; LocationComparator(final Context context) { mCollator = Collator.getInstance(context.getResources().getConfiguration().locale); } @Override public int compare(final Location object1, final Location object2) { if (object1.getWoeid() == 1) return Integer.MIN_VALUE; if (object2.getWoeid() == 1) return Integer.MAX_VALUE; return mCollator.compare(object1.getName(), object2.getName()); } } class GetAvailableTrendsTask extends AsyncTask<Object, Object, ResponseList<Location>> implements OnCancelListener { private final ProgressDialog mProgress; public GetAvailableTrendsTask(final Context context) { mProgress = new ProgressDialog(context); } @Override public void onCancel(final DialogInterface dialog) { cancel(true); } @Override protected ResponseList<Location> doInBackground(final Object... args) { final Twitter twitter = getDefaultTwitterInstance(getContext(), false); if (twitter == null) return null; try { return twitter.getAvailableTrends(); } catch (final TwitterException e) { e.printStackTrace(); } return null; } @Override protected void onPostExecute(final ResponseList<Location> result) { if (mProgress.isShowing()) { mProgress.dismiss(); } mAdapter.setData(result); if (result == null) return; final AlertDialog.Builder selectorBuilder = new AlertDialog.Builder(getContext()); selectorBuilder.setTitle(getTitle()); selectorBuilder.setSingleChoiceItems(mAdapter, mAdapter.findItemPosition(mCheckedWoeId), TrendsLocationPreference.this); selectorBuilder.setNegativeButton(android.R.string.cancel, null); mDialog = selectorBuilder.create(); final ListView lv = mDialog.getListView(); if (lv != null) { lv.setFastScrollEnabled(true); } mDialog.show(); } @Override protected void onPreExecute() { if (mProgress.isShowing()) { mProgress.dismiss(); } mProgress.setMessage(getContext().getString(R.string.please_wait)); mProgress.setOnCancelListener(this); mProgress.show(); } } }