Java tutorial
/* * Copyright 2012 Google Inc. * * 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 com.google.android.apps.iosched.util; import com.google.android.apps.iosched.BuildConfig; import com.google.android.apps.iosched.R; import com.google.android.apps.iosched.provider.ScheduleContract.Blocks; import com.google.android.apps.iosched.provider.ScheduleContract.Rooms; import com.google.android.apps.iosched.ui.phone.MapActivity; import com.google.android.apps.iosched.ui.phone.SessionDetailActivity; import com.google.android.apps.iosched.ui.phone.SessionsActivity; import com.google.android.apps.iosched.ui.phone.TrackDetailActivity; import com.google.android.apps.iosched.ui.phone.VendorDetailActivity; import com.google.android.apps.iosched.ui.tablet.MapMultiPaneActivity; import com.google.android.apps.iosched.ui.tablet.SessionsVendorsMultiPaneActivity; import android.annotation.TargetApi; import android.content.ActivityNotFoundException; import android.content.ComponentName; import android.content.Context; import android.content.Intent; import android.content.SharedPreferences; import android.content.pm.PackageManager; import android.content.pm.ResolveInfo; import android.content.res.Configuration; import android.content.res.Resources; import android.graphics.Color; import android.graphics.Typeface; import android.os.Build; import android.preference.PreferenceManager; import android.support.v4.app.FragmentActivity; import android.text.Html; import android.text.Spannable; import android.text.SpannableStringBuilder; import android.text.TextUtils; import android.text.format.DateUtils; import android.text.method.LinkMovementMethod; import android.text.style.StyleSpan; import android.view.View; import android.widget.TextView; import android.widget.Toast; import java.util.Calendar; import java.util.Formatter; import java.util.Locale; import java.util.TimeZone; /** * An assortment of UI helpers. */ public class UIUtils { /** * Time zone to use when formatting all session times. To always use the * phone local time, use {@link TimeZone#getDefault()}. */ public static TimeZone CONFERENCE_TIME_ZONE = TimeZone.getTimeZone("America/Los_Angeles"); public static long CONFERENCE_START_MILLIS = ParserUtils.parseTime("2012-06-27T09:30:00.000-07:00"); public static long CONFERENCE_END_MILLIS = ParserUtils.parseTime("2012-06-29T18:00:00.000-07:00"); public static String CONFERENCE_HASHTAG = "#io12"; private static final int SECOND_MILLIS = 1000; private static final int MINUTE_MILLIS = 60 * SECOND_MILLIS; private static final int HOUR_MILLIS = 60 * MINUTE_MILLIS; private static final int DAY_MILLIS = 24 * HOUR_MILLIS; /** Flags used with {@link DateUtils#formatDateRange}. */ private static final int TIME_FLAGS = DateUtils.FORMAT_SHOW_TIME | DateUtils.FORMAT_SHOW_WEEKDAY | DateUtils.FORMAT_ABBREV_WEEKDAY; /** {@link StringBuilder} used for formatting time block. */ private static StringBuilder sBuilder = new StringBuilder(50); /** {@link Formatter} used for formatting time block. */ private static Formatter sFormatter = new Formatter(sBuilder, Locale.getDefault()); private static StyleSpan sBoldSpan = new StyleSpan(Typeface.BOLD); private static CharSequence sEmptyRoomText; private static CharSequence sCodeLabRoomText; private static CharSequence sNowPlayingText; private static CharSequence sLivestreamNowText; private static CharSequence sLivestreamAvailableText; public static final String GOOGLE_PLUS_PACKAGE_NAME = "com.google.android.apps.plus"; /** * Format and return the given {@link Blocks} and {@link Rooms} values using * {@link #CONFERENCE_TIME_ZONE}. */ public static String formatSessionSubtitle(String sessionTitle, long blockStart, long blockEnd, String roomName, Context context) { if (sEmptyRoomText == null || sCodeLabRoomText == null) { sEmptyRoomText = context.getText(R.string.unknown_room); sCodeLabRoomText = context.getText(R.string.codelab_room); } if (roomName == null) { // TODO: remove the WAR for API not returning rooms for code labs return context.getString(R.string.session_subtitle, formatBlockTimeString(blockStart, blockEnd, context), sessionTitle.contains("Code Lab") ? sCodeLabRoomText : sEmptyRoomText); } return context.getString(R.string.session_subtitle, formatBlockTimeString(blockStart, blockEnd, context), roomName); } /** * Format and return the given {@link Blocks} values using * {@link #CONFERENCE_TIME_ZONE}. */ public static String formatBlockTimeString(long blockStart, long blockEnd, Context context) { TimeZone.setDefault(CONFERENCE_TIME_ZONE); // NOTE: There is an efficient version of formatDateRange in Eclair and // beyond that allows you to recycle a StringBuilder. return DateUtils.formatDateRange(context, blockStart, blockEnd, TIME_FLAGS); } public static boolean isSameDay(long time1, long time2) { TimeZone.setDefault(CONFERENCE_TIME_ZONE); Calendar cal1 = Calendar.getInstance(); Calendar cal2 = Calendar.getInstance(); cal1.setTimeInMillis(time1); cal2.setTimeInMillis(time2); return cal1.get(Calendar.YEAR) == cal2.get(Calendar.YEAR) && cal1.get(Calendar.DAY_OF_YEAR) == cal2.get(Calendar.DAY_OF_YEAR); } public static String getTimeAgo(long time, Context ctx) { if (time < 1000000000000L) { // if timestamp given in seconds, convert to millis time *= 1000; } long now = getCurrentTime(ctx); if (time > now || time <= 0) { return null; } // TODO: localize final long diff = now - time; if (diff < MINUTE_MILLIS) { return "just now"; } else if (diff < 2 * MINUTE_MILLIS) { return "a minute ago"; } else if (diff < 50 * MINUTE_MILLIS) { return diff / MINUTE_MILLIS + " minutes ago"; } else if (diff < 90 * MINUTE_MILLIS) { return "an hour ago"; } else if (diff < 24 * HOUR_MILLIS) { return diff / HOUR_MILLIS + " hours ago"; } else if (diff < 48 * HOUR_MILLIS) { return "yesterday"; } else { return diff / DAY_MILLIS + " days ago"; } } /** * Populate the given {@link TextView} with the requested text, formatting * through {@link Html#fromHtml(String)} when applicable. Also sets * {@link TextView#setMovementMethod} so inline links are handled. */ public static void setTextMaybeHtml(TextView view, String text) { if (TextUtils.isEmpty(text)) { view.setText(""); return; } if (text.contains("<") && text.contains(">")) { view.setText(Html.fromHtml(text)); view.setMovementMethod(LinkMovementMethod.getInstance()); } else { view.setText(text); } } public static void updateTimeAndLivestreamBlockUI(final Context context, long blockStart, long blockEnd, boolean hasLivestream, View backgroundView, TextView titleView, TextView subtitleView, CharSequence subtitle) { long currentTimeMillis = getCurrentTime(context); boolean past = (currentTimeMillis > blockEnd && currentTimeMillis < CONFERENCE_END_MILLIS); boolean present = (blockStart <= currentTimeMillis && currentTimeMillis <= blockEnd); final Resources res = context.getResources(); if (backgroundView != null) { backgroundView.setBackgroundColor(past ? res.getColor(R.color.past_background_color) : 0); } if (titleView != null) { titleView.setTypeface(Typeface.SANS_SERIF, past ? Typeface.NORMAL : Typeface.BOLD); } if (subtitleView != null) { boolean empty = true; SpannableStringBuilder sb = new SpannableStringBuilder(); // TODO: recycle if (subtitle != null) { sb.append(subtitle); empty = false; } if (present) { if (sNowPlayingText == null) { sNowPlayingText = Html.fromHtml(context.getString(R.string.now_playing_badge)); } if (!empty) { sb.append(" "); } sb.append(sNowPlayingText); if (hasLivestream) { if (sLivestreamNowText == null) { sLivestreamNowText = Html .fromHtml(" " + context.getString(R.string.live_now_badge)); } sb.append(sLivestreamNowText); } } else if (hasLivestream) { if (sLivestreamAvailableText == null) { sLivestreamAvailableText = Html.fromHtml(context.getString(R.string.live_available_badge)); } if (!empty) { sb.append(" "); } sb.append(sLivestreamAvailableText); } subtitleView.setText(sb); } } /** * Given a snippet string with matching segments surrounded by curly * braces, turn those areas into bold spans, removing the curly braces. */ public static Spannable buildStyledSnippet(String snippet) { final SpannableStringBuilder builder = new SpannableStringBuilder(snippet); // Walk through string, inserting bold snippet spans int startIndex = -1, endIndex = -1, delta = 0; while ((startIndex = snippet.indexOf('{', endIndex)) != -1) { endIndex = snippet.indexOf('}', startIndex); // Remove braces from both sides builder.delete(startIndex - delta, startIndex - delta + 1); builder.delete(endIndex - delta - 1, endIndex - delta); // Insert bold style builder.setSpan(sBoldSpan, startIndex - delta, endIndex - delta - 1, Spannable.SPAN_EXCLUSIVE_EXCLUSIVE); delta += 2; } return builder; } public static void preferPackageForIntent(Context context, Intent intent, String packageName) { PackageManager pm = context.getPackageManager(); for (ResolveInfo resolveInfo : pm.queryIntentActivities(intent, 0)) { if (resolveInfo.activityInfo.packageName.equals(packageName)) { intent.setPackage(packageName); break; } } } public static ImageFetcher getImageFetcher(final FragmentActivity activity) { // The ImageFetcher takes care of loading remote images into our ImageView ImageFetcher fetcher = new ImageFetcher(activity); fetcher.addImageCache(activity); return fetcher; } public static String getSessionHashtagsString(String hashtags) { if (!TextUtils.isEmpty(hashtags)) { if (!hashtags.startsWith("#")) { hashtags = "#" + hashtags; } if (hashtags.contains(CONFERENCE_HASHTAG)) { return hashtags; } return CONFERENCE_HASHTAG + " " + hashtags; } else { return CONFERENCE_HASHTAG; } } private static final int BRIGHTNESS_THRESHOLD = 130; /** * Calculate whether a color is light or dark, based on a commonly known * brightness formula. * * @see {@literal http://en.wikipedia.org/wiki/HSV_color_space%23Lightness} */ public static boolean isColorDark(int color) { return ((30 * Color.red(color) + 59 * Color.green(color) + 11 * Color.blue(color)) / 100) <= BRIGHTNESS_THRESHOLD; } // Shows whether a notification was fired for a particular session time block. In the // event that notification has not been fired yet, return false and set the bit. public static boolean isNotificationFiredForBlock(Context context, String blockId) { SharedPreferences sp = PreferenceManager.getDefaultSharedPreferences(context); final String key = String.format("notification_fired_%s", blockId); boolean fired = sp.getBoolean(key, false); sp.edit().putBoolean(key, true).commit(); return fired; } private static final long sAppLoadTime = System.currentTimeMillis(); public static long getCurrentTime(final Context context) { if (BuildConfig.DEBUG) { return context.getSharedPreferences("mock_data", Context.MODE_PRIVATE).getLong("mock_current_time", System.currentTimeMillis()) + System.currentTimeMillis() - sAppLoadTime; } else { return System.currentTimeMillis(); } } public static void safeOpenLink(Context context, Intent linkIntent) { try { context.startActivity(linkIntent); } catch (ActivityNotFoundException e) { Toast.makeText(context, "Couldn't open link", Toast.LENGTH_SHORT).show(); } } // TODO: use <meta-data> element instead private static final Class[] sPhoneActivities = new Class[] { MapActivity.class, SessionDetailActivity.class, SessionsActivity.class, TrackDetailActivity.class, VendorDetailActivity.class, }; // TODO: use <meta-data> element instead private static final Class[] sTabletActivities = new Class[] { MapMultiPaneActivity.class, SessionsVendorsMultiPaneActivity.class, }; public static void enableDisableActivities(final Context context) { boolean isHoneycombTablet = isHoneycombTablet(context); PackageManager pm = context.getPackageManager(); // Enable/disable phone activities for (Class a : sPhoneActivities) { pm.setComponentEnabledSetting(new ComponentName(context, a), isHoneycombTablet ? PackageManager.COMPONENT_ENABLED_STATE_DISABLED : PackageManager.COMPONENT_ENABLED_STATE_ENABLED, PackageManager.DONT_KILL_APP); } // Enable/disable tablet activities for (Class a : sTabletActivities) { pm.setComponentEnabledSetting(new ComponentName(context, a), isHoneycombTablet ? PackageManager.COMPONENT_ENABLED_STATE_ENABLED : PackageManager.COMPONENT_ENABLED_STATE_DISABLED, PackageManager.DONT_KILL_APP); } } public static Class getMapActivityClass(Context context) { if (UIUtils.isHoneycombTablet(context)) { return MapMultiPaneActivity.class; } return MapActivity.class; } @TargetApi(Build.VERSION_CODES.HONEYCOMB) public static void setActivatedCompat(View view, boolean activated) { if (hasHoneycomb()) { view.setActivated(activated); } } public static boolean isGoogleTV(Context context) { return context.getPackageManager().hasSystemFeature("com.google.android.tv"); } public static boolean hasFroyo() { // Can use static final constants like FROYO, declared in later versions // of the OS since they are inlined at compile time. This is guaranteed behavior. return Build.VERSION.SDK_INT >= Build.VERSION_CODES.FROYO; } public static boolean hasGingerbread() { return Build.VERSION.SDK_INT >= Build.VERSION_CODES.GINGERBREAD; } public static boolean hasHoneycomb() { return Build.VERSION.SDK_INT >= Build.VERSION_CODES.HONEYCOMB; } public static boolean hasHoneycombMR1() { return Build.VERSION.SDK_INT >= Build.VERSION_CODES.HONEYCOMB_MR1; } public static boolean hasICS() { return Build.VERSION.SDK_INT >= Build.VERSION_CODES.ICE_CREAM_SANDWICH; } public static boolean hasJellyBean() { return Build.VERSION.SDK_INT >= Build.VERSION_CODES.JELLY_BEAN; } public static boolean isTablet(Context context) { return (context.getResources().getConfiguration().screenLayout & Configuration.SCREENLAYOUT_SIZE_MASK) >= Configuration.SCREENLAYOUT_SIZE_LARGE; } public static boolean isHoneycombTablet(Context context) { return hasHoneycomb() && isTablet(context); } }