ci: Set ANDROID_API_VERSION

For building Qt, ANDROID_API_VERSION must be set to the target SDK.
Qt 5.12.10 needs at least android-24 (QTBUG-89616).
Google Play requires at least android-29 (as of Nov 2, 2020).

Author: dg0yt

ci/azure-pipelines.yml

@@ -111,6 +111,7 @@ jobs:
     SUPERBUILD_INSTALL_DIR: $(HOME)/superbuild
     TARGET: armv7a-linux-androideabi
     TARGET_SUFFIX: -$(TARGET)
+    ANDROID_API_VERSION: android-29
   pool:
     vmImage: '$(IMAGE_NAME)'
   steps:
@@ -138,6 +139,7 @@ jobs:
     SUPERBUILD_INSTALL_DIR: $(HOME)/superbuild
     TARGET: aarch64-linux-android
     TARGET_SUFFIX: -$(TARGET)
+    ANDROID_API_VERSION: android-29
   pool:
     vmImage: '$(IMAGE_NAME)'
   steps:
@@ -165,6 +167,7 @@ jobs:
     SUPERBUILD_INSTALL_DIR: $(HOME)/superbuild
     TARGET: i686-linux-android
     TARGET_SUFFIX: -$(TARGET)
+    ANDROID_API_VERSION: android-29
   pool:
     vmImage: '$(IMAGE_NAME)'
   steps:
@@ -192,6 +195,7 @@ jobs:
     SUPERBUILD_INSTALL_DIR: $(HOME)/superbuild
     TARGET: x86_64-linux-android
     TARGET_SUFFIX: -$(TARGET)
+    ANDROID_API_VERSION: android-29
   pool:
     vmImage: '$(IMAGE_NAME)'
   steps:

qt-5.12.10.cmake

@@ -34,6 +34,11 @@ set(openorienteering_version ${version}-qtbase-5.12.10-1)
 
 option(USE_SYSTEM_QT "Use the system Qt if possible" ON)
 
+# Note for Android
+# Set environment variable ANDROID_API_VERSION to specify the target API level.
+# Building Qt 5.12.10 needs "android-24" or higher.
+# Cf. https://bugreports.qt.io/browse/QTBUG-89616
+
 string(CONFIGURE [[
 	if("${module}" MATCHES "Android" AND NOT ANDROID)
 		set(BUILD_CONDITION 0)