/*
* Copyright (C) 2011 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 com.android.browser;
import android.os.Looper;
import android.util.Log;
import android.webkit.WebView;
/**
* Centralised point for controlling WebView timers pausing and resuming.
*
* All methods on this class should only be called from the UI thread.
*/
public class WebViewTimersControl {
private static final boolean LOGD_ENABLED = com.android.browser.Browser.LOGD_ENABLED;
private static final String LOGTAG = "WebViewTimersControl";
private static WebViewTimersControl sInstance;
private boolean mBrowserActive;
private boolean mPrerenderActive;
/**
* Get the static instance. Must be called from UI thread.
*/
public static WebViewTimersControl getInstance() {
if (Looper.myLooper() != Looper.getMainLooper()) {
throw new IllegalStateException("WebViewTimersControl.get() called on wrong thread");
}
if (sInstance == null) {
sInstance = new WebViewTimersControl();
}
return sInstance;
}
private WebViewTimersControl() {
}
private void resumeTimers(WebView wv) {
if (LOGD_ENABLED) Log.d(LOGTAG, "Resuming webview timers, view=" + wv);
if (wv != null) {
wv.resumeTimers();
}
}
private void maybePauseTimers(WebView wv) {
if (!mBrowserActive && !mPrerenderActive && wv != null) {
if (LOGD_ENABLED) Log.d(LOGTAG, "Pausing webview timers, view=" + wv);
wv.pauseTimers();
}
}
public void onBrowserActivityResume(WebView wv) {
if (LOGD_ENABLED) Log.d(LOGTAG, "onBrowserActivityResume");
mBrowserActive = true;
resumeTimers(wv);
}
public void onBrowserActivityPause(WebView wv) {
if (LOGD_ENABLED) Log.d(LOGTAG, "onBrowserActivityPause");
mBrowserActive = false;
maybePauseTimers(wv);
}
public void onPrerenderStart(WebView wv) {
if (LOGD_ENABLED) Log.d(LOGTAG, "onPrerenderStart");
mPrerenderActive = true;
resumeTimers(wv);
}
public void onPrerenderDone(WebView wv) {
if (LOGD_ENABLED) Log.d(LOGTAG, "onPrerenderDone");
mPrerenderActive = false;
maybePauseTimers(wv);
}
}