Java tutorial
/* * Copyright (C) 2006 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 android.widget; import android.content.Context; import android.database.ContentObserver; import android.os.Handler; import android.os.SystemClock; import android.provider.Settings; import android.text.format.DateFormat; import android.util.AttributeSet; import java.util.Calendar; /** * Like AnalogClock, but digital. * * @deprecated It is recommended you use {@link TextClock} instead. */ @Deprecated public class DigitalClock extends TextView { // FIXME: implement separate views for hours/minutes/seconds, so // proportional fonts don't shake rendering Calendar mCalendar; @SuppressWarnings("FieldCanBeLocal") // We must keep a reference to this observer private FormatChangeObserver mFormatChangeObserver; private Runnable mTicker; private Handler mHandler; private boolean mTickerStopped = false; String mFormat; public DigitalClock(Context context) { super(context); initClock(); } public DigitalClock(Context context, AttributeSet attrs) { super(context, attrs); initClock(); } private void initClock() { if (mCalendar == null) { mCalendar = Calendar.getInstance(); } } @Override protected void onAttachedToWindow() { mTickerStopped = false; super.onAttachedToWindow(); mFormatChangeObserver = new FormatChangeObserver(); getContext().getContentResolver().registerContentObserver(Settings.System.CONTENT_URI, true, mFormatChangeObserver); setFormat(); mHandler = new Handler(); /** * requests a tick on the next hard-second boundary */ mTicker = new Runnable() { public void run() { if (mTickerStopped) return; mCalendar.setTimeInMillis(System.currentTimeMillis()); setText(DateFormat.format(mFormat, mCalendar)); invalidate(); long now = SystemClock.uptimeMillis(); long next = now + (1000 - now % 1000); mHandler.postAtTime(mTicker, next); } }; mTicker.run(); } @Override protected void onDetachedFromWindow() { super.onDetachedFromWindow(); mTickerStopped = true; getContext().getContentResolver().unregisterContentObserver(mFormatChangeObserver); } private void setFormat() { mFormat = DateFormat.getTimeFormatString(getContext()); } private class FormatChangeObserver extends ContentObserver { public FormatChangeObserver() { super(new Handler()); } @Override public void onChange(boolean selfChange) { setFormat(); } } @Override public CharSequence getAccessibilityClassName() { //noinspection deprecation return DigitalClock.class.getName(); } }