WebView cause memory leak.

WebView problems description:

1. WebView cause memory leak in Android core and high CPU usage if Javascript enabled.

Bug reports on Android bug tracker

• https://code.google.com/p/android/issues/detail?id=21355
• https://code.google.com/p/android/issues/detail?id=9375

How to reproduce?

• Create test project with WebView
• Load some URL few times with WebView.loadUrl()
• see memory leak

Same problem here with example application

Full Solution - not found.

It's official bug.

Solution (not solution, but works)

Disable javascript support at all
webView.setJavaScriptEnabled(false)

Partial solution 1

call the onPause / onResume on the webview to reduce CPU usage

• CPU usage decreased
• Memory leak present

code:

Class.forName("android.webkit.WebView").getMethod("onPause", (Class[]) null).invoke(webView, (Object[]) null);

[Detail on Android bug tracker][link 3]

Partial solution 2

• loadDataWithBaseURL

WebView.loadDataWithBaseURL(url,data,"text/html","UTF-8",url);

Fine for static page, but not for site in Internet.

Partial solution 3

Disable all...

 mWebView.getSettings().setAppCacheEnabled(false);
mWebView.getSettings().setCacheMode(WebSettings.LOAD_NO_CACHE);
mWebView.getSettings().setDatabaseEnabled(false);
mWebView.getSettings().setDomStorageEnabled(false);
mWebView.getSettings().setGeolocationEnabled(false);
mWebView.getSettings().setPluginsEnabled(false);
mWebView.getSettings().setSaveFormData(false);
mWebView.getSettings().setSavePassword(false);

clean up, destroy, create new WebView

 mWebView.removeAllViews();
mWebView.destroyDrawingCache();
mWebView.clearCache(true);
mWebView.clearHistory();
mWebView.freeMemory();
mWebView.destroy();
mWebView = null;

Memory leak present

Links

• http://askprogramming.com/38624/webview-threads-never-stop-webviewcorethread-cookiesyncmanager-http0-3.html
• http://stackoverflow.com/questions/2040963/webview-threads-never-stop-webviewcorethread-cookiesyncmanager-http0-3
• https://code.google.com/p/android/issues/detail?id=10282
• http://stackoverflow.com/questions/17352757/android-webview-javascript-memory-leak
• http://stackoverflow.com/questions/12803309/android-webview-asset-reference-memory-leak
• http://arrindel-janu1991.blogspot.com/2013/08/webviewcorethread-waits-indefinetely.html
• https://code.google.com/p/android/issues/detail?id=12987
• http://stackoverflow.com/questions/6415182/android-clear-webview-thread-free-memory-avoid-outofmemoryerror

2. OutOfMemoryException

See problem 1 and http://stackoverflow.com/questions/6497780/webview-outofmemoryexception

3. WebView causes memory leak - leaks the parent Activity

Starting an activity with a WebView, then destroying that activity (hitting back) and getting a heap dump shows that there are uncleaned up references that cause the activity to stay in memory (leak).

Links

• https://code.google.com/p/android/issues/detail?id=5067
• http://stackoverflow.com/questions/19303904/android-fragment-webview-memory-leak

4. WebView threads never stop (WebViewCoreThread, CookieSyncManager, http[0-3]) [detail][link 1]

I use a WebView to display some internet content on one of our app's Activities. The problem is that when the user switches out of this activity, WebView's threads keep running!

• http://askprogramming.com/38624/webview-threads-never-stop-webviewcorethread-cookiesyncmanager-http0-3.html
• http://stackoverflow.com/questions/2040963/webview-threads-never-stop-webviewcorethread-cookiesyncmanager-http0-3