TimeButton, button

TimeButton, button

The countdown button is needed in the company's project. Handler + Runnable is used, which is always very troublesome. Later, I learned that the CountDownTimer function is provided in the API and pasted on it. Let's take a look at the button with the countdown function: Very simple, that is, CountDownTimer is called.

Package com. helper. view; import android. content. context; import android. graphics. color; import android. OS. countDownTimer; import android. OS. handler; import android. OS. message; import android. util. attributeSet; import android. widget. button;/*** Created by deadline on 2015/8/28. * Button with countDown function */public class TimeButton extends Button {private static final int DEFAULT_COUNTDOWN = 60; private int countDown; private int beforeColor; private int afterColor; private CountDownTimer timer; public TimeButton (Context context) {this (context, null);} public TimeButton (Context context, AttributeSet attrs) {this (context, attrs, 0 );} public TimeButton (final Context context, AttributeSet attrs, int defStyleAttr) {super (context, attrs, defStyleAttr); beforeColor = Color. DKGRAY; afterColor = Color. parseColor ("# 0085cf"); countDown = DEFAULT_COUNTDOWN; setTextColor (beforeColor); setText ("Get Verification Code"); timer = new CountDownTimer (countDown * 1000,100 0) {@ Override public void onTick (long millisUntilFinished) {// The remaining time is in milliseconds. setText (String. valueOf (millisUntilFinished/1000) + "s can be retrieved again");} @ Override public void onFinish () {setEnabled (true); setTextColor (afterColor ); setText ("re-obtain Verification Code") ;};}/ *** Start countdown * 0 seconds not visible, directly switch to clickable status */public void startCountdown () {setTextColor (beforeColor); setEnabled (false); // you cannot click timer. start ();} public void stop () {timer. cancel ();} public int getCountDown () {return countDown;} public void setCountDown (int countDown) {this. countDown = countDown;} public int getAfterColor () {return afterColor;} public void setAfterColor (int afterColor) {this. afterColor = afterColor;} public int getBeforeColor () {return beforeColor;} public void setBeforeColor (int beforeColor) {this. beforeColor = beforeColor ;}}

package android.os;/** * Schedule a countdown until a time in the future, with * regular notifications on intervals along the way. * * Example of showing a 30 second countdown in a text field: * * <pre class="prettyprint"> * new CountDownTimer(30000, 1000) { * *     public void onTick(long millisUntilFinished) { *         mTextField.setText("seconds remaining: " + millisUntilFinished / 1000); *     } * *     public void onFinish() { *         mTextField.setText("done!"); *     } *  }.start(); * </pre> * * The calls to {@link #onTick(long)} are synchronized to this object so that * one call to {@link #onTick(long)} won't ever occur before the previous * callback is complete.  This is only relevant when the implementation of * {@link #onTick(long)} takes an amount of time to execute that is significant * compared to the countdown interval. */public abstract class CountDownTimer {    /**     * Millis since epoch when alarm should stop.     */    private final long mMillisInFuture;    /**     * The interval in millis that the user receives callbacks     */    private final long mCountdownInterval;    private long mStopTimeInFuture;    /**    * boolean representing if the timer was cancelled    */    private boolean mCancelled = false;    /**     * @param millisInFuture The number of millis in the future from the call     *   to {@link #start()} until the countdown is done and {@link #onFinish()}     *   is called.     * @param countDownInterval The interval along the way to receive     *   {@link #onTick(long)} callbacks.     */    public CountDownTimer(long millisInFuture, long countDownInterval) {        mMillisInFuture = millisInFuture;        mCountdownInterval = countDownInterval;    }    /**     * Cancel the countdown.     */    public synchronized final void cancel() {        mCancelled = true;        mHandler.removeMessages(MSG);    }    /**     * Start the countdown.     */    public synchronized final CountDownTimer start() {        mCancelled = false;        if (mMillisInFuture <= 0) {            onFinish();            return this;        }        mStopTimeInFuture = SystemClock.elapsedRealtime() + mMillisInFuture;        mHandler.sendMessage(mHandler.obtainMessage(MSG));        return this;    }    /**     * Callback fired on regular interval.     * @param millisUntilFinished The amount of time until finished.     */    public abstract void onTick(long millisUntilFinished);    /**     * Callback fired when the time is up.     */    public abstract void onFinish();    private static final int MSG = 1;    // handles counting down    private Handler mHandler = new Handler() {        @Override        public void handleMessage(Message msg) {            synchronized (CountDownTimer.this) {                if (mCancelled) {                    return;                }                final long millisLeft = mStopTimeInFuture - SystemClock.elapsedRealtime();                if (millisLeft <= 0) {                    onFinish();                } else if (millisLeft < mCountdownInterval) {                    // no tick, just delay until done                    sendMessageDelayed(obtainMessage(MSG), millisLeft);                } else {                    long lastTickStart = SystemClock.elapsedRealtime();                    onTick(millisLeft);                    // take into account user's onTick taking time to execute                    long delay = lastTickStart + mCountdownInterval - SystemClock.elapsedRealtime();                    // special case: user's onTick took more than interval to                    // complete, skip to next interval                    while (delay < 0) delay += mCountdownInterval;                    sendMessageDelayed(obtainMessage(MSG), delay);                }            }        }    };}

Copyright Disclaimer: This article is an original article by the blogger and cannot be reproduced without the permission of the blogger.