refactor: Post Qt 6 cleanup #863

1. 
   hebasto commented at 7:54 pm on April 2, 2025: member

   This PR:

   • Removes outdated Qt version-specific code.
   • Inlines two functions from GUIUtil.
2. qt, refactor: Remove outdated Qt version-specific code

   Since bitcoin/bitcoin#30997, the minimum supported Qt version is 6.2.

   4b36ab3a6a
3. qt, refactor: Inline `GUIUtil::GetImage` function d1ec6db249
4. qt, refactor: Inline `GUIUtil::SplitSkipEmptyParts` function 3aa58bea8e
5. hebasto added the label Refactoring on Apr 2, 2025
6. 
   DrahtBot commented at 7:54 pm on April 2, 2025: contributor

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7. in src/qt/qrimagewidget.cpp:99 in d1ec6db249 outdated

    91@@ -92,7 +92,11 @@ bool QRImageWidget::setQR(const QString& data, const QString& text)
    92 
    93 QImage QRImageWidget::exportImage()
    94 {
    95-    return GUIUtil::GetImage(this);
    96+    if (!GUIUtil::HasPixmap(this)) {
    97+        return QImage();
    98+    }
    99+
   100+    return this->pixmap(Qt::ReturnByValue).toImage();
   

   ---

   ---

   

   davidgumberg commented at 8:50 pm on April 2, 2025:

   Micro-Nit:

   As far as I understand this is deprecated in favor of QLabel::pixmap() at least as early as QT 6.2 (https://doc.qt.io/archives/qt-6.2/qlabel-obsolete.html#pixmap) and was marked obsolete in 6.0 (https://doc.qt.io/archives/qt-6.0/qlabel-obsolete.html#pixmap)

   Previously, it was recommended to use QLabel::pixmap(Qt::ReturnByValue) to maintain compatibility with old code, since previously QLabel::pixmap() returned a pixmap by pointer. (https://doc.qt.io/qt-5/qlabel.html#pixmap-prop)

   0    return this->pixmap().toImage();
   

8. 
   davidgumberg commented at 9:34 pm on April 2, 2025: contributor

   crACK https://github.com/bitcoin-core/gui/pull/863/commits/3aa58bea8e703e33a1eb8e2f9fdf887aca8d03c1

   Nice cleanup, doesn’t change any behavior, mostly drops workaround code for versions of QT < 6.2.

   ---

   Left an insignificant nit about use of deprecated QLabel::pixmap(Qt::ReturnByValue()), but this can be addressed in a follow up (or here, if the author prefers) with the other place it appears.

   (https://github.com/davidgumberg/gui/commit/ca5390f9b0af348e8f4ea0cf2149716c0b77bd8f)

    0diff --git a/src/qt/guiutil.cpp b/src/qt/guiutil.cpp
    1@@ -959,7 +959,7 @@ QDateTime StartOfDay(const QDate& date)
    2 bool HasPixmap(const QLabel* label)
    3 {
    4-    return !label->pixmap(Qt::ReturnByValue).isNull();
    5+    return !label->pixmap().isNull();
    6 }
    7
    8diff --git a/src/qt/qrimagewidget.cpp b/src/qt/qrimagewidget.cpp
    9@@ -96,7 +96,7 @@ QImage QRImageWidget::exportImage()
   10         return QImage();
   11     }
   12-    return this->pixmap(Qt::ReturnByValue).toImage();
   13+    return this->pixmap().toImage();
   14 }
   

9. 
   hebasto commented at 7:43 am on April 3, 2025: member

   @davidgumberg

   crACK 3aa58be

   Nice cleanup, doesn’t change any behavior, mostly drops workaround code for versions of QT < 6.2.

   Thank you for your review!

   Left an insignificant nit about use of deprecated QLabel::pixmap(Qt::ReturnByValue()), but this can be addressed in a follow up (or here, if the author prefers) with the other place it appears.

   (davidgumberg@ca5390f)

    0diff --git a/src/qt/guiutil.cpp b/src/qt/guiutil.cpp
    1@@ -959,7 +959,7 @@ QDateTime StartOfDay(const QDate& date)
    2 bool HasPixmap(const QLabel* label)
    3 {
    4-    return !label->pixmap(Qt::ReturnByValue).isNull();
    5+    return !label->pixmap().isNull();
    6 }
    7
    8diff --git a/src/qt/qrimagewidget.cpp b/src/qt/qrimagewidget.cpp
    9@@ -96,7 +96,7 @@ QImage QRImageWidget::exportImage()
   10         return QImage();
   11     }
   12-    return this->pixmap(Qt::ReturnByValue).toImage();
   13+    return this->pixmap().toImage();
   14 }
   

   I agree with your comment and suggested changes. I also agree that this can be addressed in a follow-up, along with other closely related changes, such as inlining the QRImageWidget::exportImage() function.

10. hebasto merged this on Apr 3, 2025
11. hebasto closed this on Apr 3, 2025

    ---

12. hebasto deleted the branch on Apr 3, 2025

Contributors
hebasto DrahtBot davidgumberg

Labels
Refactoring