com.codename1.ui.util.UITimer Maven / Gradle / Ivy
/*
* Copyright (c) 2012, Codename One and/or its affiliates. All rights reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation. Codename One designates this
* particular file as subject to the "Classpath" exception as provided
* by Oracle in the LICENSE file that accompanied this code.
*
* This code 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
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Please contact Codename One through http://www.codenameone.com/ if you
* need additional information or have any questions.
*/
package com.codename1.ui.util;
import com.codename1.ui.Display;
import com.codename1.ui.Form;
import com.codename1.ui.Graphics;
import com.codename1.ui.animations.Animation;
/**
* Simple timer callback that is invoked on the CodenameOne EDT thread rather
* than on a separate thread. Notice that the accuracy of this timer is very low!
* A timer must be linked to a specific form
*
* @author Shai Almog
*/
public class UITimer {
private Runnable internalRunnable;
private Form bound;
private long lastEllapse;
private int ms;
private boolean repeat;
private Internal i = new Internal();
/**
* This constructor is useful when deriving this class to implement a timer.
*/
protected UITimer() {
}
/**
* Constructor that accepts a runnable to invoke on timer elapse
*
* @param r runnable instance
*/
public UITimer(Runnable r) {
internalRunnable = r;
}
/**
* Binds the timer to start at the given schedule
*
* @param timeMillis the time from now in milliseconds
* @param repeat whether the timer repeats
* @param bound the form to which the timer is bound
*/
public void schedule(int timeMillis, boolean repeat, Form bound) {
lastEllapse = System.currentTimeMillis();
ms = timeMillis;
this.repeat = repeat;
this.bound = bound;
bound.registerAnimated(i);
}
/**
* Convenience method to schedule a UITimer more easily
* @param timeMillis the time from now in milliseconds
* @param repeat whether the timer repeats
* @param parent the form to which the timer is bound
* @param r callback when the timer elapses
* @return the timer instance
*/
public static UITimer timer(int timeMillis, boolean repeat, Form parent, Runnable r) {
UITimer uit = new UITimer(r);
uit.schedule(timeMillis, repeat, parent);
return uit;
}
/**
* Convenience method to schedule a UITimer more easily on the current form
* @param timeMillis the time from now in milliseconds
* @param repeat whether the timer repeats
* @param r callback when the timer elapses
* @return the timer instance
*/
public static UITimer timer(int timeMillis, boolean repeat, Runnable r) {
UITimer uit = new UITimer(r);
uit.schedule(timeMillis, repeat, Display.getInstance().getCurrent());
return uit;
}
/**
* Stops executing the timer
*/
public void cancel() {
if(bound != null) {
bound.deregisterAnimated(i);
}
}
void testEllapse() {
long t = System.currentTimeMillis();
if(t - lastEllapse >= ms) {
if(!repeat) {
Display.getInstance().getCurrent().deregisterAnimated(i);
}
lastEllapse = t;
i.run();
}
}
class Internal implements Runnable, Animation {
/**
* {@inheritDoc}
*/
public boolean animate() {
testEllapse();
return false;
}
/**
* {@inheritDoc}
*/
public void paint(Graphics g) {
}
/**
* Invoked when the timer elapses
*/
public void run() {
if(internalRunnable != null) {
internalRunnable.run();
}
}
}
}