Merge #79: Embed monospaced font

67f26319a0ca7e34e3db17d9330133622a40de09 gui: Add monospaced font settings (Hennadii Stepanov)
22e0114d055b0ac6cdc47af2968b5dc742ba055a qt: Choose monospaced font in C++ code rather in `*.ui` file (Hennadii Stepanov)
623de12d040af89ff7c25de6eb0a19c67179dc5f qt: Make GUIUtil::fixedPitchFont aware of embedded font (Hennadii Stepanov)
89e421918ee8b9c8439317f747e5c37f0733d94b gui: Add Roboto Mono font (Hennadii Stepanov)

Pull request description:

  Qt does not guarantee that the actual applied font matches to the requested one.
  It was noted (https://github.com/bitcoin/bitcoin/pull/16432#issuecomment-514486077):
  > the monospace font looks a bit weird no macOS

  ... because it is _not_ monospaced.
  Also some discrepancies I've noted on Windows while testing Qt 5.15 ([#19716](https://github.com/bitcoin/bitcoin/pull/19716)).

  Of course, we could check the actual font with `QFontInfo`, and try to choose another font.
  But this PR suggests to just embed a monospaced font, and get the GUI look (partially) independent from a platform.

  [Roboto Mono](https://fonts.google.com/specimen/Roboto+Mono) was chosen after discussion with Bitcoin Design community, and due to its [Apache License, Version 2.0](https://fonts.google.com/specimen/Roboto+Mono#license).

  Changes are scoped to the Overview page only.

  ---

  Screenshots on macOS 10.15.6 (images are simulated by code patching):

  - master (ca30d34cf94b7797272ef1920ca4b48716e7f999)
  ![Screenshot from 2020-09-03 14-10-03](https://user-images.githubusercontent.com/32963518/92107902-30357d80-edef-11ea-8a4f-b4c758eebf66.png)

  - this PR (3fdd5b6bd17a679d6e3876682266092159c52d59)
  ![Screenshot from 2020-09-03 15-41-36](https://user-images.githubusercontent.com/32963518/92116277-4b5aba00-edfc-11ea-8cb9-22fc44460bfb.png)

  ---

  More screenshots added after https://github.com/bitcoin-core/gui/pull/79#issuecomment-782909149:

  - Linux Mint 20.1 + Cinnamon DE

  ![DeepinScreenshot_select-area_20210221205410](https://user-images.githubusercontent.com/32963518/108635739-b327be80-7489-11eb-8851-ac89f61199ee.png)

  - Windows 10 (with depends)

  ![DeepinScreenshot_select-area_20210221205056](https://user-images.githubusercontent.com/32963518/108635741-b6bb4580-7489-11eb-8b6b-66be5551eb8c.png)

  - macOS Big Sur (with depends)

  ![DeepinScreenshot_select-area_20210221202917](https://user-images.githubusercontent.com/32963518/108635746-bd49bd00-7489-11eb-8cd2-cf4bb2273a6d.png)

ACKs for top commit:
  laanwj:
    Tested ACK 67f26319a0ca7e34e3db17d9330133622a40de09

Tree-SHA512: a59775570b8ce314669ede50a0b69f53e8a47a41e7eea428835013240f0ce9afcff6e4c258895455b56806417ed877e5b7a9522f1904e95a5f435db8ccf6078c

2 files changed, 100 insertions, 56 deletions

diff --git a/src/qt/forms/optionsdialog.ui b/src/qt/forms/optionsdialog.ui
index 8181cc47e2..6d279540e9 100644
--- a/src/qt/forms/optionsdialog.ui
+++ b/src/qt/forms/optionsdialog.ui
@@ -706,6 +706,106 @@
         </layout>
        </item>
        <item>
+        <widget class="QGroupBox" name="font_groupBox">
+         <property name="title">
+          <string>Monospaced font in the Overview tab:</string>
+         </property>
+         <layout class="QVBoxLayout" name="font_verticalLayout">
+          <item>
+           <layout class="QHBoxLayout" name="embeddedFont_horizontalLayout">
+            <item>
+             <widget class="QRadioButton" name="embeddedFont_radioButton">
+              <property name="text">
+               <string>embedded &quot;%1&quot;</string>
+              </property>
+             </widget>
+            </item>
+            <item>
+             <spacer name="embeddedFont_horizontalSpacer">
+              <property name="orientation">
+               <enum>Qt::Horizontal</enum>
+              </property>
+              <property name="sizeHint" stdset="0">
+               <size>
+                <width>40</width>
+                <height>20</height>
+               </size>
+              </property>
+             </spacer>
+            </item>
+            <item>
+             <layout class="QVBoxLayout" name="embeddedFont_verticalLayout">
+              <item>
+               <widget class="QLabel" name="embeddedFont_label_1">
+                <property name="text">
+                 <string>111.11111111 BTC</string>
+                </property>
+               </widget>
+              </item>
+              <item>
+               <widget class="QLabel" name="embeddedFont_label_9">
+                <property name="text">
+                 <string>909.09090909 BTC</string>
+                </property>
+               </widget>
+              </item>
+             </layout>
+            </item>
+           </layout>
+          </item>
+          <item>
+           <widget class="Line" name="font_line">
+            <property name="orientation">
+             <enum>Qt::Horizontal</enum>
+            </property>
+           </widget>
+          </item>
+          <item>
+           <layout class="QHBoxLayout" name="systemFont_horizontalLayout">
+            <item>
+             <widget class="QRadioButton" name="systemFont_radioButton">
+              <property name="text">
+               <string>closest matching &quot;%1&quot;</string>
+              </property>
+             </widget>
+            </item>
+            <item>
+             <spacer name="systemFont_horizontalSpacer">
+              <property name="orientation">
+               <enum>Qt::Horizontal</enum>
+              </property>
+              <property name="sizeHint" stdset="0">
+               <size>
+                <width>40</width>
+                <height>20</height>
+               </size>
+              </property>
+             </spacer>
+            </item>
+            <item>
+             <layout class="QVBoxLayout" name="systemFont_verticalLayout">
+              <item>
+               <widget class="QLabel" name="systemFont_label_1">
+                <property name="text">
+                 <string>111.11111111 BTC</string>
+                </property>
+               </widget>
+              </item>
+              <item>
+               <widget class="QLabel" name="systemFont_label_9">
+                <property name="text">
+                 <string>909.09090909 BTC</string>
+                </property>
+               </widget>
+              </item>
+             </layout>
+            </item>
+           </layout>
+          </item>
+         </layout>
+        </widget>
+       </item>
+       <item>
         <spacer name="verticalSpacer_Display">
          <property name="orientation">
           <enum>Qt::Vertical</enum>
diff --git a/src/qt/forms/overviewpage.ui b/src/qt/forms/overviewpage.ui
index ee9d4a113c..b82143e1ba 100644
--- a/src/qt/forms/overviewpage.ui
+++ b/src/qt/forms/overviewpage.ui
@@ -116,13 +116,6 @@
             </property>
             <item row="2" column="2">
              <widget class="QLabel" name="labelWatchPending">
-              <property name="font">
-               <font>
-                <family>Monospace</family>
-                <weight>75</weight>
-                <bold>true</bold>
-               </font>
-              </property>
               <property name="cursor">
                <cursorShape>IBeamCursor</cursorShape>
               </property>
@@ -142,13 +135,6 @@
             </item>
             <item row="2" column="1">
              <widget class="QLabel" name="labelUnconfirmed">
-              <property name="font">
-               <font>
-                <family>Monospace</family>
-                <weight>75</weight>
-                <bold>true</bold>
-               </font>
-              </property>
               <property name="cursor">
                <cursorShape>IBeamCursor</cursorShape>
               </property>
@@ -168,13 +154,6 @@
             </item>
             <item row="3" column="2">
              <widget class="QLabel" name="labelWatchImmature">
-              <property name="font">
-               <font>
-                <family>Monospace</family>
-                <weight>75</weight>
-                <bold>true</bold>
-               </font>
-              </property>
               <property name="cursor">
                <cursorShape>IBeamCursor</cursorShape>
               </property>
@@ -227,13 +206,6 @@
             </item>
             <item row="3" column="1">
              <widget class="QLabel" name="labelImmature">
-              <property name="font">
-               <font>
-                <family>Monospace</family>
-                <weight>75</weight>
-                <bold>true</bold>
-               </font>
-              </property>
               <property name="cursor">
                <cursorShape>IBeamCursor</cursorShape>
               </property>
@@ -273,13 +245,6 @@
             </item>
             <item row="5" column="1">
              <widget class="QLabel" name="labelTotal">
-              <property name="font">
-               <font>
-                <family>Monospace</family>
-                <weight>75</weight>
-                <bold>true</bold>
-               </font>
-              </property>
               <property name="cursor">
                <cursorShape>IBeamCursor</cursorShape>
               </property>
@@ -299,13 +264,6 @@
             </item>
             <item row="5" column="2">
              <widget class="QLabel" name="labelWatchTotal">
-              <property name="font">
-               <font>
-                <family>Monospace</family>
-                <weight>75</weight>
-                <bold>true</bold>
-               </font>
-              </property>
               <property name="cursor">
                <cursorShape>IBeamCursor</cursorShape>
               </property>
@@ -342,13 +300,6 @@
             </item>
             <item row="1" column="1">
              <widget class="QLabel" name="labelBalance">
-              <property name="font">
-               <font>
-                <family>Monospace</family>
-                <weight>75</weight>
-                <bold>true</bold>
-               </font>
-              </property>
               <property name="cursor">
                <cursorShape>IBeamCursor</cursorShape>
               </property>
@@ -368,13 +319,6 @@
             </item>
             <item row="1" column="2">
              <widget class="QLabel" name="labelWatchAvailable">
-              <property name="font">
-               <font>
-                <family>Monospace</family>
-                <weight>75</weight>
-                <bold>true</bold>
-               </font>
-              </property>
               <property name="cursor">
                <cursorShape>IBeamCursor</cursorShape>
               </property>