Add keyboard shortcuts to context menus

[luke-jr]

Various keyboard shortcuts were lost in #263; this restores them, and also adds new ones for other context menus.

Note that with a context menu open, simply the shortcut by itself (no Alt) is used.

[hebasto]

Note that with a context menu open, simply the shortcut by itself (no Alt) is used.

As pointed by @luke-jr on IRC:

<luke-jr> no idea, it's an OS behaviour, not Qt-specific

[jarolrod]

Concept ACK

This introduces mnemonic shortcuts for the context menu actions: QShortcut Documentation

On certain widgets, using '&' in front of a character will automatically create a mnemonic (a shortcut) for that character, e.g. "E&xit" will create the shortcut Alt+X (use '&&' to display an actual ampersand). The widget might consume and perform an action on a given shortcut.

This is a UX improvement and improves the accessibility of the GUI as well as convenience.

Tested functionality on Arch Linux Qt 5.15.2, Windows 7,8,10 cross-compiled from Linux, and macOS 11.3 Qt 5.15.2.

Linux

Mnemonic shortcuts work well. I need to hit ALT in order to learn about what the shortcuts are. Because of this, the OP is misleading in saying:

Note that with a context menu open, simply the shortcut by itself (no Alt) is used.
A user needs to know about a shortcut before they can use it, and to know about it ALT is required.

Master	PR

Windows 7-10

The mnemonics work on Windows 7,8, and 10. But again, ALT is required to learn about the shortcuts.

Master	PR

macOS

mnemonics aren't really supported on macOS, so it is ok that they do not work well on macOS:

However, because mnemonic shortcuts do not fit in with Aqua's guidelines, Qt will not show the shortcut character underlined.

If there is no mechanism to highlight the shortcut, then it is useless as a user would need to dig through the source code to learn about them.

Testing on macOS, the mnemonics work if you know the correct key, press it, then press enter. This is surprising as Qt docs states:

On Mac, shortcuts are disabled by default. Call qt_set_sequence_auto_mnemonic() to enable them.

I see no difference in behavior applying the following patch, so i think this is a poorly documented part of Qt and must have changed:

diff --git a/src/qt/bitcoingui.cpp b/src/qt/bitcoingui.cpp
index 3d632ec70..3266ca13c 100644
--- a/src/qt/bitcoingui.cpp
+++ b/src/qt/bitcoingui.cpp
@@ -28,6 +28,7 @@
 
 #ifdef Q_OS_MAC
 #include <qt/macdockiconhandler.h>
+    extern void qt_set_sequence_auto_mnemonic(bool b);
 #endif
 
 #include <functional>
@@ -214,6 +215,7 @@ BitcoinGUI::BitcoinGUI(interfaces::Node& node, const PlatformStyle *_platformSty
 
 #ifdef Q_OS_MAC
     m_app_nap_inhibitor = new CAppNapInhibitor;
+    qt_set_sequence_auto_mnemonic(true);
 #endif

[jarolrod]

@hebasto

hebasto added this to the 22.0 milestone yesterday

What about the translation freeze?

[hebasto]

@jarolrod

Testing on macOS, the mnemonics work if you know the correct key, press it, then press enter. This is surprising as Qt docs states:

On Mac, shortcuts are disabled by default. Call qt_set_sequence_auto_mnemonic() to enable them.

Sound like a Qt bug :)

---

hebasto added this to the 22.0 milestone yesterday

What about the translation freeze?

From bitcoin/bitcoin#20851:

2021-06-01 heavy_check_mark

* Open Transifex translations for 22

* Soft translation string freeze (no large or unnecessary string changes until release)

* Finalize and close translations for 0.20

2021-06-15 construction

* Feature freeze (bug fixes only until release)

* Translation string freeze (no more source language changes until release)

As this PR fixes the behavior regression introduced in #263, it could be considered as "necessary string changes".

[hebasto]

Approach ACK 94e7cdd, modulo #362 (comment).

[hebasto]

ACK e4c916a, tested on Linux Mint 20.1 (Qt 5.12.8).

Also checked that 02b5263 reverts 7931175.

[jarolrod]

Code Review ACK e4c916a