Library editor: Use GraphicsScene::itemsBoundingRect() to select all items

[BuFran]

The currentGraphicsItem is always empty (there is no insert anywhere) so it returned always empty rect.

After this PR, for selectAll functionality, the entire graphicsScene for retrieving entire content rect is used.

Maybe the solution is wrong, probably I missed intent of currentGraphicsItem. The board and schematic does this differently.

One architecture misconception is that on symbol it is reference, on package it is shared pointer so probably there is really unfinished rework.

There should be no style bugs because I tried to run dev/format_code.sh 😃

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Added by @ubruhin:

Fixes #1179

[ubruhin]

I think the code makes sense 👍 Will quickly test it soon.

One architecture misconception is that on symbol it is reference, on package it is shared pointer so probably there is really unfinished rework.

No, this is on purpose. A symbol always consists of exactly one graphics item (the symbol) so we can use a reference. But a package consists of 0..n footprints, and thus 0..n graphics items. In case of 0 footprints, we don't have any graphics to display so it will be nullptr.

There should be no style bugs because I tried to run dev/format_code.sh 😃

Awesome :) By the way, since you are contributing regularly, I may tell you some more things about our preferred workflow 🙂

We prefer commit messages according this recommendation (see also CONTRIBUTING.md). It may sound picky, but it really helps to keep the Git log readable and messages easy to understand if every contributor follows the same style.

For example the GitHub issue should not be mentioned in the first line of the commit message. Just describe what you did in this commit (e.g. "Library editor: Use GraphicsScene::itemsBoundingRect() to select all items"). If the commit closes a particular GitHub issue, just write "Closes #nnn" at the end of the PR body - this will make GitHub to close the issue automatically when merging the PR so we don't have to do it manually.

So far our preference, but especially for simpler PRs where a single commit is enough, don't worry too much about it. This is also an advantage of squash-merge that the final commit message can easily be adjusted in the GitHub UI 🙈

[ubruhin]

Seems to work fine, thanks!