I've just recently become interested in programming, and I want to create Android apps for phones or tablets. I've come a long way in a couple weeks from knowing almost nothing about java/xml. I'm very serious about this. I'm going to find the answer to this question one way or the other. In fact, I hope to have it figured out before anyone answers this. I've fixed many issues without resorting to asking anyone, but I've just been stuck on this issue too long. I figured I'd give this a shot.
I'm using an older tutorial to build a practice twitter app (the tutorials for these seem to be everywhere, which is why I chose it). I'm using Eclipse for an editor.
The following is an example of code from the tutorial. which relates to my question:
#Override
public void onCreate (Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.timeline);
Apparently since the intro of ADT 14, you can no longer use the (R.layout.timeline) phrase, which the error message refers to as a "switch statement."
Now, in a post I found on another site, someone who had a similar issue shows a screenshot of the "quick fix" in Eclipse using ctrl+1. in the screenshot, the fix that pops up says "convert switch to 'if-else' statement." This fix does not pop up in my version of Eclipse. My quick fix options are "migrate Android code", "create field 'timeline' in type 'layout'", "create constant 'timeline' in type 'layout'" or "rename in file."
If I choose "migrate Android code", a window pops up informing me of the ADT 14 update, and how switch statements are no longer allowed in library projects. It says to convert the switch statement to an "if-else" statement by pressing ctrl+1 for the quick fix, then choosing "switch to 'if-else' statement" like it does in the screenshot I found. But again, when I do this, that option does not pop up.
I would much rather know what needs to be changed in the code than know how to make the right quick fix pop up. If it isn't too much trouble, an explanation of why exactly these changes are affective would be very helpful. I have many (MANY) errors in my java files right now, but most of them are due to this exact problem in different forms. If I could see just one before/after example I could probably figure it out from there without an explanation. But after hours of searching, I cannot find that so far by googling.
Thanks so much in advance....
And for the record, I don't see any switch classes in any of my java files, if that makes a difference for the answer...
Make sure you click on the switch keyword itself then press Ctrl + 1.
This confused me at first as well...
If it still doesn't show up, what version of Eclipse are you using?
If you are using a Mac select the keyword switch and click Shift + Command + 1.
That will show a prompt to change switch to if else conditions.
I've been having the same issues. For me, I was switching on view.getId(). Before the switch, declare int id = view.getId();. Then switch in id. Then you can ctrl+1 click and the "Convert Switch to If/Else" should pop up.
They made this change to decrease the build speed. My projects now build in roughly 1/10th of the time. I'm glad I upgraded the ADT.
The issue happens because since ADT 14 resource identifiers are no longer final.
The quick solution you can change switch statements with if-else statements.
With Android Studio 4.1.3
Step:1. Just right click on the switch keyword of statement.
Step:2 Click on the first option Show Context Actions.
Step:3 Click replace switch with if.
Done
To me, it looks like you don't have a timeline resource.
Breaking down R.layout.timeline
R refers to Resources
layout refers to the collection of layouts in your application
and timeline refers the specific resource that you are trying to apply setContentView() too.
If my hunch is correct, you don't have the timeline resource.
Create a new XML file in your layout folder in eclipse and name it 'timeline'
That should resolve the issue.
I hope you got things working.
I agree that this sounds like some weird Eclipse error that is not what it seems, and not what Quick Fix says it is. Eclipse has been known to lie from time to time. Cleaning your project (as #Stephen Dubya said), cutting out the offending code, saving the file, pasting it back in, and saving again...these are some of the non-obvious tricks that sometimes get Eclipse to behave.
In general, I think it would be good for you to get more familiar with some of the Java basics like switch; I think it will make your learning of Android a lot easier. Although the tools and documentation keep improving, Android is still young and not always easy to learn using tutorials, especially when you aren't used to writing code at all or using complicated IDEs like Eclipse.
But I digress. It is only in Android library projects, not regular projects, that Android doesn't treat resources as constants (final variables), since ADT 14. That means means that in library projects, you can't use R.layout.timeline or similar resource variables in your switch statements. You can only switch on whole numbers or enum values.
Using if-else all the time may be your best bet, anyway. switch can, especially for beginners, lead to logic errors in your code, and anything you can write using switch can be rewritten using if-else blocks. Personally, I've stopped using switch in Android and other Java code altogether.
You need to place the curse right before the s in the word switch, and the press cmd 1 . If you switch statements have fall-through clauses, the option to convert won't be available.
Somehow I overworked this error. I have deleted my project from workspace. Reverted it's .project files to old ones commited at SVN. Then at Eclipse uninstalling ADT and install it again. Then import my project. - > Libraries are added the old way and as result all fields at R.java are now final. Hope this helps.
Related
After a long period of creating apps with Android Studio I returned to Eclipse to program a pure Java application. Of course, I have noticed large differences in terms of auto completion between IntelliJ IDEA and Eclipse but IntelliJ is no alternative for me because of various reasons.
That is why I started to change the settings in Eclipse, inter alia, for the content assist. I want to have suggestions for variable names too, without having to write a dot first. As you can see in this image, I have changed the auto activation triggers to ._#abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ as suggested in another thread on Stack Overflow.
The problem is, if I write short variable names like d it completes them automatically to something different (in this case DEFAULT_CURSOR) when I press the dot key. To avoid this, I have to choose the variable first, before pressing the dot key.
However, having to do it this way is a large waste of time. Is there a possibility to use the suggested variables or methods only when I have pressed the enter key, just like in IntelliJ?
Maybe there is an option to bind the dot key to the closing of the content assist?
No, Eclipse and IntelliJ are different and IntelliJ's level of auto completion is unique to itself. If you are comfortable with it, you should use it and then copy and paste to eclipse for windowbuilder. Also FYI there is a free alternative to windowbuilder for IntelliJ, you can read about it here: WindowBuilder equivalent for IntelliJ?
I'm using Intellij for Java development. In the code editor on the right, it displays some yellow markers which indicate issue with my code, e.g. improvement suggestions. When I hover over the affected code line it tell me what to do. Unfortunately I didn't find a way of automatically applying said suggestion. How do I do that? I don't want to do fixes by hand but rather allow Intellij to do them for convenience.
CTRL + Space is only code completion.
Just place the cursor over the highlighted code, hit Alt+Enter, select the suggested fix and hit Enter.
You can also apply the fix for all problems of the given type within specified scope (current file, project, ...). If you want to do that, just select Run inspection on from the menu that is shown.
I'm not sure if there is a way to apply these fixes automatically completely without user intervention, but even if there was, it probably wouldn't be very user friendly, as the warnings are sometimes false-positive.
If you want to apply a code suggestion it it simply Alt+Enter while the cursor is over the highlighted code. I would strongly suggest not automatically applying suggestions and to use your better judgement.
I can personally attest that while it's a little extra work, being able to choose the suggestions validity is much better. There's been more than a few times when the suggestion wouldn't make sense in the context.
As a sidenote I'd suggest having a reference for the KB shortcuts open so you can improve your speed within the IDE: Mac or Windows/Linux
I've encountered a weird glitch in Android Studio:
As you can see it thinks that it is an error:
'class' or 'interface' expected
But it runs and build just fine, so is this just a visual glitch or can it have any effect during compiling?
I'm running Android Studio 0.5.8 for Mac
Things I've tried so far:
Restart Android Studio
Restart MacBook
Invalidate caches and restart
tried other strings (like "en-US" this result in the same effect)
If I use a string through the resources the glitch isn't visible (which it will be eventually, I'm just curious why this is happening)
IntelliJ and Android Studio have the ability to take string parameters and treat the strings as being in another language. For example, if you have a method that takes a string that's HTML, if you tell the IDE about it, it can give you syntax highlighting and content assist with the HTML in that string.
I think you've inadvertently set this string as being treated as Java, and it's giving you the Java syntax errors on it. You need to un-set that setting. Select the text, bring up the Search Action feature (on Mac it's ⌘ shift a). In the search box that comes up, search for Un-inject Language/Reference, as shown in the screenshot below:
try this
httpReqquest.addHeader("Accept-Language","en-US");
Since Android Studio is a bit raw, you can face the "glitches" in many different ways. They're annoying but don't affect the result, as you said. However, I personally don't think that we should endure the inconveniences (even if the Studio costs nothing).
I see a couple of solutions:
Continue with AS and ignore these weird things, hoping they will release a robust software once
Or, to migrate to IntelliJ IDEA as I did. The procedure is pricey but it's worth it.
I am very new to Eclipse, java programming and well all "programming" in general and I have recently been learning how to use Eclipse. I've been using it for about a week now and it has been going decent so far. Apart from some errors,(mostly on my part) that has been fixable by restarting the program itself.
However when I started using it today I could no longer see the suggestions made from the Quick Fix command, for example if I type findVi and then press CTRL+1, it shows "No suggestions available" instead of "findViewById()" or something similar.
I know it's the correct binding, I even reset the keys to default to be sure. It still finds the ID if i type it manually but I would like to able to finish words faster that way.
If you guys got any suggestions that can help me out, please let me know.
Thanks.
- First of all if you are new with Java, and want to practice Java, you should NEVER USE ANY IDE, that way you learn the proper syntax, and it helps your error finding skills.
- But as you wrote "findViewById()" it seems that you are doing Android, Now this happens sometimes that Eclipse behaves weirdly with Android. Thats the reason when you make any changes into your Eclipse GUI while working with Android, its always better to see if those changes have taken effect.
- This problem usually goes off after closing and re-opening the Eclipse once or twice.
- Ok try this....
Type findVie then press Ctrl + Space-Bar See if the suggestion pops up...
You can access the Content Assist preferences from Window > Preferences > Java > Editor > Content Assist... perhaps something got messed up.
So for example with my current object tabPanelMain, I'll type a dot after it and expect to see a drop down menu of all the object's available methods. Instead, the marker which shows my currently selected character on the editor disappears meaning I don't know where I'm typing. Worse than that is that the save and save all buttons stop working. And ctrl-s and the menu saves don't work either. I can't save my eclipse projects and have to restart, thus losing my work.
What could be wrong? This problem never used to exist but now I just can't get the methods of an object like I used to.
I hope that was clear enough, please ask me questions if not.
The save problem with not being able to save is one I've encountered before.
I don't know why it happens but for me it helps to minimize and then maximize eclipse again.
Not a fix but at least a workaround that lets you save.
Never heard of the other problem though.
I couldn't figure out what it was that was causing the problem, and while Martin Larsson provided an effective short term solution, I found it best to fresh install Eclipse.
The most annoying part about this was transferring my previous plug ins (like GWT, Subversion, etc) over to the new install. In the end I ended up re-installing them manually. If anyone could shed some light on how to keep previous plug ins, I'd like to hear how. Though I've heard this can be problematic with path urls in the files or something.