Somehow I broke Eclipse's Hotswap Bug Fixing feature where editing the Java code, Eclipse resets the currently executing line and allows you to continue debugging...all without restarting the debugging session. This was working perfectly a week ago. Now when I edit and save the Java source, the debugger stays at the same line and continues running as if I didn't maky any changes.
I'm going to be embarrassed when you tell me what I'm did wrong to break this. :-( :-)
This is the question and answer here that asks my exact question. Unfortunately, the answer is obsolete or at least I can't find the answer on the page.
Eclipse :Edit the source and continue debugging
After more than three months, I discovered how to fix this!
I needed to turn on "Build Automatically" in the Project menu.
Once checked, the hot-restart began working and my debugging productivity increased dramatically.
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?
"Debugception!"
You may notice that within the first 15 seconds of this YouTube video (from 1:01:01 to 1:01:16), Markus Persson (aka "Notch", creator of Minecraft) has somehow managed to save/update an application and attach a debugger to it while it was already under the process of being debugged, supposedly all with a simple keyboard shortcut. The previously coded application somehow magically became the newly edited one, and seemingly without relaunching it or spawning a new process... It's possible that this is just some form of locally remote debugging, but something about it just doesn't seem quite right.
I've spent several days Googling and asking around on how he was able to do this, yet to no avail. I've found no such option under Eclipse preferences, and whenever I try to save & debug an already running application, it simply launches a separate instance of the newly updated application, side-by-side with the older, outdated one.
Am I missing something? How was this possible?
How was he able to utilize such an astounding, powerful debugging feature?
Thanks in advance!
Update
Okay, so this appears to be a standard feature specific to Eclipse.
Coming from a background in NetBeans and Visual Studio, I'm astounded that this doesn't seem to exist elsewhere (or at least in NetBeans!)...
This is a built-in feature of Eclipse. If you edit a method while the program is running in debug mode, it will compile the new method, and replace the old method with the new version. If some thread was already running that method, it will jump back to the beginning (AFAIK; this might only happen when the program is paused).
You don't need to re-launch the program or set any special preferences. Just edit and save, and the magic will happen.
Eclipse can't always figure out how to merge your changes into the running program - usually if you changed anything outside a method body (including the method's parameters or return type). In this case, you will get a warning dialog, with the option to stop the program, restart the program or ignore the changes.
sometimes when I debug in Eclipse, I found some thing wrong so I want come back and debug again, but I want to do that just for couple statements.
I saw
How to step back in Eclipse debugger?
is it possible to "go back" in java eclipse debugger like dragging the arrow in VS
and I know about Drop to frame but I can't use this to step back any line I want. I need some thing else. For example if you use debug in Visual Studio, you can drag and drop the debug arrow anywhere you want. You can bring the debugger to previous statement and debug it again. I need something like this in Eclipse but Drop to frame doesn't do that.
Thanks.
The linked answers suggest to use a third-party product to provide exactly this feature. If you don't want to do that and are not satisfied with drop to frame, there is one more option. You can set a breakpoint before the interesting place (or just drop to that frame), and then evaluate arbitrary code in this context (see Eclipse Help or this blog post).
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.