Getting info about a Class in IntelliJ IDE by hovering over it - intellij-idea

In EClipse if I hold the mouse over a class name I get some hint like the picture below about it:
But with doing the same I don't get that hint box in IntellijIDEA.(Mac edition)
Is there a setting somewhere to set this? It is really helpful.

For anybody new finding this question there is also an option for it

You can press CTRL + Q when hovering above a class name to show a popup with more information.

To know the classname and it's initial declaration within the scope, use Ctrl + J (Mac OS)

Related

How to show all methods quickly in Intellij Idea?

Look at this picture, I should open the Structure window every time in Intellij Idea whenever I want to know methods in the class.
Is there a simple way or shortcut to show methods quicky what like CTRL + O in Eclipse.
Ctrl+F12 should pop up a member list. It will respond to text input to search/filter, too.

How do I copy and paste the tooltip error message that pops up in IntelliJ IDEA?

IntelliJ IDEA automatically shows a red line if it cannot resolve some entities or it detects an error. Is there a way to copy and paste the content of that tooltip?
With eclipse I use the f2 to get the information.
I used the idea version 14.1.4 and use this way to copy the tooltips.
You can click the error line and the info will display, now you can right click to copy this error info.
Mouse shortcut:
Hover mouse over error in editor to bring up tooltip
Alt + click on error message inside tooltip to copy it to clipboard
For step 1 you can also bring up the tooltip for the current carret position by Ctrl + F1. For step 2 there does not seem to exist a keyboard shortcut at the time of writing (for IntelliJ 2018.1), see also IDEA-65636.
If you stumbled upon looking for solution for Linux version (and none of the above worked for you, like for me) click ctrl+alt+left mouse button on the tooltip, and you'll get its content into the clipboard :)
No, the tooltips don't offer a way to get that information from their context alone.
You could traditionally compile it instead via Build -> Compile and get the error message that way, instead. You can then select this text and do with it what you wish.
There is a bug report on this since 2011 (!) . Feel free /encouraged to vote for having the bug fixed:
https://youtrack.jetbrains.com/issue/IDEA-65636
IDEA-65636 I can't copy text from tooltip, though I can select it
Though honestly JetBrains infrequently gets around to non super critical bug fixes.

Intellij idea quick defenition

In eclipse when I mouse over a variable I see it quick defenition, when I mouse over with shift pressed, I see full defenition. But in idea, I always need to press some keys to do anything. Is there a way to simplify those tasks in idea?
The quick definition features is accessible with the shortcut ctrl + shift + I.
I don't think it's possible to access to it on a key + the mouse over.
You can edit the idea.properties found in the bin folder of IntelliJ application and add this line:
auto.show.quick.doc=true
The
This will give you the JavaDoc when hovering over a variable:

XCode Show Function Parameters Hotkey

One of the few things I haven't figured out how to do in XCode that I could do in Visual Studio is list the parameters of a function. I've Googled this a few times now, and still haven't found an answer.
If I start typing out, for example round( I get a list of the parameters and its return type. However, if I already typed out the code
x = round(y);
and I cursor over to it, I don't know how to show parameter info without retyping it. Anyone know how the hotkey for this?
Just discovered Option + Escape by browsing through the XCode Preferences Hotkeys section. It actually lists the parameter info in a tooltip (no other hotkey I've seen so far does this!), but isn't quite as friendly as Visual Studio's Ctrl+Shift+Space function. For instance, the text selection cursor (caret) must be on the function name (not on a parameter to that function).
Having explored the XCode hotkeys exhaustively, I'm going to assume that this is the best it gets in XCode.
Control + Command + Shift + / is the keyboard equivalent of Option + click mentioned in other answers
Command + click the function will navigate you to the function definition, while Option + click brings up tooltip of function definition.

How can I display documentation in Xcode via CodeSense?

I am Java developer and would like to know how I can get the equivalent of a JavaDoc in Xcode when CodeSense is doing its auto-complete? If I hit the ESC button I can get a list of methods etc. but it does not show me the descriptions of what the methods do.
I am new to xcode and mac. Bring your mouse over the method name and press alt + left mouse click to see help. To see full help press alt + double mouse left click.
It's not quite the same, but the close equivalent is Quick Help, accessible from the Help Menu. It's a floating palette that dynamically shows a quick documentation for the method or class at your cursor position.
Just to add to the topic, on Xcode 13 you can invoke quick help by using:
⌥ (option) + mouse click
On any method, function, structure and etc...