I read Android documents and also I find deprecated methods and classes in that.Can I use deprecated methods and classes in android studio?
Can I use them like other methods and classes that are not deprecated?
Yes you can use deprecated methods as long as the depreciated method exists in the framework. By deprecating a method the platform developers are trying to tell you that either something is wrong with the method or there is already better way for doing the task.
Depricating a method is like giving a warning to the developers not to use that method as the chances are high that the deprecated methods will be removed in the future release and your application which uses that method may no longer work when your users updates the platform to the latest release.
Of course you can use deprecated methods, they should still work as intended. But you have to be careful, because they could be removed in future versions. So read the comments.
This discussion gives you further information Is it wrong to use Deprecated methods or classes in Java?
The description of the Java Deprecated annotation can be found here http://docs.oracle.com/javase/1.5.0/docs/api/java/lang/Deprecated.html
It says
A program element annotated #Deprecated is one that programmers are
discouraged from using, typically because it is dangerous, or because
a better alternative exists. Compilers warn when a deprecated program
element is used or overridden in non-deprecated code.
Of course you can use them just that they can be removed in future update which makes it dangerous for your apps and end user.
To get more info read the android documentation on it. https://developer.android.com/reference/java/lang/Deprecated
As a victim, my advice for you is NO because there's a time i used a deprecated method of androidx ViewPager instead of the modern one. Although it worked fine but after keeping the app idle for some days, then it could no longer open if i tried to open it
Related
I was about to use the android class Sound Pool when I noticed it has become deprecated. Should I try to find the newest version every-time or just use the deprecated method?
Real answer? Never.
It is deprecated for a reason. Deprecated methods are methods that will not be updated and may cease to be supported at all. Try to find the newest way of doing what you want to do with the most up-to-date API.
From: http://docs.oracle.com/javase/1.5.0/docs/api/java/lang/Deprecated.html
A program element annotated #Deprecated is one that programmers are discouraged from using, typically because it is dangerous, or because a better alternative exists.
There is a better way to do it, but that doesn't mean you cant do it. You are probably safe, but you will have to keep an eye on performance, especially for android.
I am working on a huge android project with tons of classes. Until now we are compiling with Android 3.2 and giving support to Android 2.3.
Now I am testing to compile with Android 5.1.1, but still giving support to Android 2.3. My surprise was that a lot of code is deprecated now... (getWith(), getDrawable(), setBackgroundDrawable(), HttpRequest, ActivityGroup, etc...). Those deprecated functions does not give compile error, but it gives deprecated warning.
I know that I can duplicate code and make special calls to deprecated methods if SDK_INT is lower than XX and calls to new methods if SDK_INT is newer than XX, but this is a huge patch, that will need a lot of duplicate code in a lot of functions in a ton of classes and packages, so, if it is possible, we prefeer to wait until we don't need to give support to oldest versions of android. It means to continue using deprecated methods until for example we only need to give support from 4.4, that will means munch less duplicated code and functions will be needed.
The question is: If i compile with Android 5.1.1 but still use those deprecated functions, this huge project will continue to work on all devices (from 2.3 to 5.1.1)? Now it's working compiling with Android 3.2.
I understand that Deprecated means that they are likely to be removed in a future version of the platform and so you should begin looking at replacing their use in your code, but if it is still supported and does not give a compile error, it will work well as until now. It is what I understand of deprecation. It is right?
Thanks.
Deprecated means two things:
There is another (maybe better) solution
It isn't fully support anymore
That means that your code could be run fine. But Google/Android don't guarantee that.
According to Java documentation the #Deprecated annotation says:
#Deprecated annotation indicates that the marked element is deprecated and should no longer be used. The compiler generates a warning whenever a program uses a method, class, or field with the #Deprecated annotation. [...]
So please stop using deprecated methods. :)
Have you looked or do you know that there are support-libraries to help you with backward compatibility?
Yes it should work fine. But you really should use the latest methods instead of deprecated ones and use support libraries to make it compatible to the previous versions.
All the deprecated methods that I have used have worked fine, but Google does not guarantee that they will.
You can continue using deprecated methods, they should still work as intended. But you have to be careful, because they could be removed in future versions.
As mentioned in the documention over developer.android.com
A program element annotated #Deprecated is one that programmers are
discouraged from using, typically because it is dangerous, or because
a better alternative exists. Compilers warn when a deprecated program
element is used or overridden in non-deprecated code.
It may stop working with new version.
Example: LocationManager.addNmeaListener(GpsStatus.NmeaListener listener)
Deprecated from API 24.
Stop Working in API 29 (Android 10). No implementation inside (returns false).
In documentation: No-op method to keep backward-compatibility.
Had trouble to find why old code stop working.
Some methods are marked with a line on it. Is this some kind of error ?? this thing bothers me but the applications work fine.
Deprecated methods. That means that there are newer alternative methods available to be used which are more compatible. Deprecated methods do work, but Google does not guarantee their proper functioning. And support for those methods may be ended in future versions of android.
They are deprecated. Consider using ones who aren't.
I like to use the findAll/ findAllAsync method in android.webkit.WebView. findAll is deprecated and Google suggests to use findAllAsync which requires Jelly Bean or higher. However, I like my application to support 2.2+. I tried to the following, but I get warning for findAll (deprecation) and error for findAllAysnc (need to increment minimum SDK version):
if (Build.VERSION.SDK_INT < Build.VERSION_CODES.JELLY_BEAN) {
myWebView.findAll(query);
else
{
myWebView.findAllAsync(query);
}
What's the best way to deal with this? Should I just use findAll and ignore the deprecation warning?
I believe the answer goes in several ways:
What are you setting as min SDK version and target SDK version in the manifest ?
Same question, but in Eclipse (or whatever IDE you're using) for Android build API properties ?
(I'm answering as if your question is "how do I get rid of the android lint warning", rather than "how do I fix the warning correctly" .. )
Use findAll and if the warning is really too annoying add a #SuppressWarning("deprecation") annotation to suppress it explicitly.
One problem with this is that when you use this annotation on your method you might miss other deprecated calls as it will apply to the whole method.
There's a very interesting and powerful way of doing what you want, and it is called reflection. From the Oracle's Java documentation:
Reflection is commonly used by programs which require the ability to
examine or modify the runtime behavior of applications running in the
Java virtual machine. This is a relatively advanced feature and should
be used only by developers who have a strong grasp of the fundamentals
of the language.
In short, reflection allows you to find out if class is defined, you can find out its methods and properties, and invoke a class' functionality... all at runtime!
I have an app that needs to handle the audio focus on Android 2.1 devices but the Audio Focus is not available for those versions, so I use this technique. It is, by the way, a bumpy road. I would suggest reading carefully the documentation and try to follow some examples.
I see quite a few good old useful methods or even entire classes being "deprecated and obsolete".
But code that used to call those methods continues to work. So, what does this mean to me, as an Android applications developer?
Continue using this method as long as I want, because newer SDKs
will always remain backward compatible.
It will work as long as I build for older targets (e.g. API 8), but
if I build from API 14 up, the compiler will refuse to complete
the build.
Both (1) and (2)
Other?
This is especially confusing when no alternatives are provided, as in the case of WebView.PictureListener.html#onNewPicture.
It usually means that there's either a better way of doing things or that the deprecated functionality had some irreparable flaw and should be avoided. You can usually keep using deprecated methods, but you are advised to either switch to some new API (in the first case) or find some other way of doing what you want (in the second).
Regarding onNewPicture in particular, the entire PictureListener interface is deprecated. There's no sign of what, if anything, is supposed to replace it. A comment by #CommonsWare in this thread is food for thought:
It is conceivable that upstream changes in WebKit are driving the deprecation and that support for PictureListener might be totally lost in some future release.
I would go with 4:
It will basically tell you that the use of the method or class is discouraged; it is NOT 100% that they will keep backward compatibility (they can decide to not include that method in future releases), so you should try to use the replacement of the method or class. This is sometimes not possible to use the new methods (for instance, if you want to support devices running older versions).
Some other times it is actually possible. For instance, the showDialog method is now deprecated and they recommend to use DialogFragment class. You can achieve that even in older versions of Android by using the compatibility library.
Deprecated methods are not guaranteed to remain backwards compatible. They might remain in there for a few more releases just to give everyone a chance to migrate away from them before the developers remove them. The fact that they're deprecated means that the developers think that there's an easier, faster, neater, or otherwise better way to do whatever that class or method does.
It's probably better to change your code to use a non-deprecated interface now, since if you wait and it does get removed, your users will see crashes and errors.
Even when they are deprecated, they may compile but not work. Google has decided to delete various functionality at the low OS level.
Case in point. Google, at android release 2.3 deprecated many but not all method API's that allowed call recording. They compile OK but do not function since Android 2.3 and forward on any android phone device, or tablet with phone capabilities.
As an example for a deprecated interface that has been removed in a later API level, consider the org.apache.http package: It has been deprecated in API level 22 and removed in API level 23.
Of course on actual Android devices, the classes contained in that package will still be available in the system libraries (otherwise, applications targeting an older Android release would no longer run on that device).
They are however not available in the SDK anymore, so compilation will fail unless you either change the target/build SDK to an older version (or manually include the deprecated classes).
If Google were really determined to discourage use of those libraries, they could modify the implementation so that the affected classes check the target API version of the running application and complain and/or throw a runtime exception.