Summary: Otherwise the content overflows the frame when scrolling. QQC2 scrollview docs say "ScrollView does not automatically clip its contents. If it is not used as a full-screen item, you should consider setting the clip property to true" Test Plan: Before: {F8121150} After: {F8121152} Reviewers: #kwin, #plasma, ngraham Reviewed By: ngraham Subscribers: ngraham, kwin Tags: #kwin Differential Revision: https://phabricator.kde.org/D27558
86 lines
2.5 KiB
Markdown
86 lines
2.5 KiB
Markdown
# Coding Conventions
|
|
|
|
This document describes some of the recommended coding conventions that should be followed in KWin.
|
|
|
|
For KWin, it is recommended to follow the KDE Frameworks Coding Style.
|
|
|
|
|
|
## `auto` Keyword
|
|
|
|
Optionally, you can use the `auto` keyword in the following cases. If in doubt, for example if using
|
|
`auto` could make the code less readable, do not use `auto`. Keep in mind that code is read much more
|
|
often than written.
|
|
|
|
* When it avoids repetition of a type in the same statement.
|
|
|
|
```
|
|
auto something = new MyCustomType;
|
|
auto keyEvent = static_cast<QKeyEvent *>(event);
|
|
auto myList = QStringList({ "FooThing", "BarThing" });
|
|
```
|
|
|
|
* When assigning iterator types.
|
|
|
|
```
|
|
auto it = myList.const_iterator();
|
|
```
|
|
|
|
|
|
## `QRect::right()` and `QRect::bottom()`
|
|
|
|
For historical reasons, the `QRect::right()` and `QRect::bottom()` functions deviate from the true
|
|
bottom-right corner of the rectangle. Note that this is not the case for the `QRectF` class.
|
|
|
|
As a general rule, avoid using `QRect::right()` and `QRect::bottom()` as well methods that operate
|
|
on them. There are exceptions, though.
|
|
|
|
Exception 1: you can use `QRect::moveRight()` and `QRect::moveBottom()` to snap a `QRect` to
|
|
another `QRect` as long as the corresponding borders match, for example
|
|
|
|
```
|
|
// Ok
|
|
rect.moveRight(anotherRect.right());
|
|
rect.moveBottom(anotherRect.bottom());
|
|
rect.moveBottomRight(anotherRect.bottomRight());
|
|
|
|
// Bad
|
|
rect.moveRight(anotherRect.left() - 1); // must be rect.moveLeft(anotherRect.left() - rect.width());
|
|
rect.moveBottom(anotherRect.top() - 1); // must be rect.moveTop(anotherRect.top() - rect.height());
|
|
rect.moveBottomRight(anotherRect.topLeft() - QPoint(1, 1));
|
|
```
|
|
|
|
Exception 2: you can use `QRect::setRight()` and `QRect::setBottom()` to clip a `QRect` by another
|
|
`QRect` as long as the corresponding borders match, for example
|
|
|
|
```
|
|
// Ok
|
|
rect.setRight(anotherRect.right());
|
|
rect.setBottom(anotherRect.bottom());
|
|
rect.setBottomRight(anotherRect.bottomRight());
|
|
|
|
// Bad
|
|
rect.setRight(anotherRect.left());
|
|
rect.setBottom(anotherRect.top());
|
|
rect.setBottomRight(anotherRect.topLeft());
|
|
```
|
|
|
|
Exception 3: you can use `QRect::right()` and `QRect::bottom()` in conditional statements as long
|
|
as the compared borders are the same, for example
|
|
|
|
```
|
|
// Ok
|
|
if (rect.right() > anotherRect.right()) {
|
|
return;
|
|
}
|
|
if (rect.bottom() > anotherRect.bottom()) {
|
|
return;
|
|
}
|
|
|
|
// Bad
|
|
if (rect.right() > anotherRect.left()) {
|
|
return;
|
|
}
|
|
if (rect.bottom() > anotherRect.top()) {
|
|
return;
|
|
}
|
|
```
|