Develop Reference

ConstraintLayout doesn't match with the screen size

I just started my first Android Studio project and I already come with a problem :)
I search on google for the answer but didn't find my problem.
So I need your help please ^^
I download the last version of Android Studio, create a project with an Empty Activity and I came up with this
As you can see my ConstraintLayout is really small and I just can't work with this.
I didn't touch anything on the project. Just to be sure I create 3 projects that have the same issue and redownload 4 time Android Studio.
On the virtual Devices, it looks correct throw: Screenshot
I put the XML code just in case it can help
xmlcode
Hope I was clear and sorry for my English ;)
EDIT: For some reason, the constraint layout fit correctly on the watch screen, but I don't want to create a watch app x) screenshot_watchview

Ok so I have finally find the problem ! I'm so happy right now :D
The problem was the AppTheme theme that I use, I switch it with the DeviceDefault theme. I don't know why this theme was causing problem but now it work and I can finally work on my first Android App !

If you are using the supportLibrary 28+ then this thing happened to me too.
and when I change the support lib version to the 27, it works.
Maybe this is a possible bug in the support library 28+.
Changing the AppTheme works like a charm if you want to stick with the support library 28+ But if you still don't want to so Try using the support library below 28.

Strange lines appearing on Android Studio design view

Personally I have no problem with Android Studio, but one of the people on my course is having a strange problem with the design view. Lines and boxes keep appearing and are causing problems and after researching profusely for the last couple of hours I've been able to find no mention of what they are or how to get rid of them anywhere on the internet.
I found one other stack overflow post about these that had been submitted a couple of months ago, however it unfortunately featured no replies. I've added the screenshot from this post just to save me getting one but it's the same problem.
Does anybody know how to get rid of these? Or what they are? Because they don't show on my Android Studio.
The screenshot
Thanks in advance.

maybe it just some bugs appeared on install?
Try to just:
1. File - > clear cache and exit
2. Reinstall studio
3. Install studio 3.0 in early access
Hope it will help)

Android Studio 2.3.1 Component Tree and Palette missing

I updated Android Studio to 2.3.1. Now, when I´m trying to edit a layout through graphic mode, component tree and Palette are not visible anywhere. I have searched too much in Google and I have could not found something that solve the problem. Thanks for your time and attention. Excuse my posible poor english.

Try Restore default layout from window menu, normally you can use the shortcut shift+f12

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I am trying to develop an android app. But when I create another Activity, the design page displays Exception raised during rendering: android.graphics.drawable.VectorDrawable_Delegate.nCreateTreeFromCopy(JJ)J.

If I understood you correctly, you should change the preview API level from version 24 to 23, attached id a screenshot of same issue, if is then solve as above.
If I did not get you, then please clarify. Good luck.

How to create different layout compatible for Android Tablet

I am developing application for Android3.0 which must be compatible for all tablet size. When i googled for my problem i got a solution as in below link
Multiple Screen Resoultion
When i am trying this, i got another problem as showing error as "w600dp, Portrait Orientation' is not a best match for any device/locale combination"
For this problem i have googled and got the final solution as in following link as Eclipse spits out a cryptic error message. What ever i have tried i didnt solve my problem
Can anyone please give me solution.
Thanks in advance..