Removes JSON constructor from UI elements

This fixes the error: clang:optin.cplusplus.VirtualCall
When virtual methods are called during construction and destruction the polymorphism is restricted to the class that’s being constructed or destructed because the more derived contexts are either not yet initialized or already destructed.

tests/UI_button.cpp

@@ -5,7 +5,8 @@ TEST(UI_button, to_from_json)
 {
     UI_button button("button_text", Color(255, 255, 255), Color(0, 0, 0), nullptr);
     json j = button.to_json(0);
-    UI_button button2(j);
+    UI_button button2;
+    button2.from_json(j);
     EXPECT_EQ(button.text(), button2.text());
     EXPECT_EQ(button.fg_color(), button2.fg_color());
     EXPECT_EQ(button.bg_color(), button2.bg_color());

tests/UI_checkbox.cpp

@@ -4,7 +4,8 @@ TEST(UI_checkbox, to_from_json)
 {
     UI_checkbox checkbox("checkbox_text", Color(255, 255, 255), Color(0, 0, 0));
     json j = checkbox.to_json(0);
-    UI_checkbox checkbox2(j);
+    UI_checkbox checkbox2;
+    checkbox2.from_json(j);
     EXPECT_EQ(checkbox.text(), checkbox2.text());
     EXPECT_EQ(checkbox.fg_color(), checkbox2.fg_color());
     EXPECT_EQ(checkbox.bg_color(), checkbox2.bg_color());

tests/UI_combobox.cpp

@@ -2,11 +2,12 @@
 
 TEST(UI_combobox, to_from_json)
 {
-    UI_combobox checkbox(Color(255, 255, 255), Color(0, 0, 0), {"option1", "option2"});
-    json j = checkbox.to_json(0);
-    UI_combobox checkbox2(j);
-    EXPECT_EQ(checkbox.text(), checkbox2.text());
-    EXPECT_EQ(checkbox.fg_color(), checkbox2.fg_color());
-    EXPECT_EQ(checkbox.bg_color(), checkbox2.bg_color());
-    EXPECT_EQ(checkbox.selected(), checkbox2.selected());
+    UI_combobox combobox(Color(255, 255, 255), Color(0, 0, 0), {"option1", "option2"});
+    json j = combobox.to_json(0);
+    UI_combobox combobox2;
+    combobox2.from_json(j);
+    EXPECT_EQ(combobox.text(), combobox2.text());
+    EXPECT_EQ(combobox.fg_color(), combobox2.fg_color());
+    EXPECT_EQ(combobox.bg_color(), combobox2.bg_color());
+    EXPECT_EQ(combobox.selected(), combobox2.selected());
 }

tests/UI_dial.cpp

@@ -4,7 +4,8 @@ TEST(UI_dial, to_from_json)
 {
     UI_dial dial("slider_text", Color(255, 255, 255), Color(0, 0, 0), 0, 100, 50);
     json j = dial.to_json(0);
-    UI_dial dial2(j);
+    UI_dial dial2;
+    dial2.from_json(j);
     EXPECT_EQ(dial.text(), dial2.text());
     EXPECT_EQ(dial.fg_color(), dial2.fg_color());
     EXPECT_EQ(dial.bg_color(), dial2.bg_color());

tests/UI_label.cpp

@@ -10,7 +10,8 @@ TEST(UI_label, to_from_json)
     EXPECT_EQ(j["fg_color"], "#000000FF");
     EXPECT_EQ(j["bg_color"], "#FFFFFFFF");
 
-    UI_label label2(j);
+    UI_label label2;
+    label2.from_json(j);
     EXPECT_EQ(label2.text(), "label_text");
     EXPECT_EQ(label2.fg_color(), Color(0, 0, 0));
     EXPECT_EQ(label2.bg_color(), Color(255, 255, 255));

tests/UI_led.cpp

@@ -4,7 +4,8 @@ TEST(UI_led, to_from_json)
 {
     UI_led led("led_text", Color(0, 0, 0), Color(255, 255, 255));
     json j = led.to_json(0);
-    UI_led led2(j);
+    UI_led led2;
+    led2.from_json(j);
     EXPECT_EQ(led.text(), led2.text());
     EXPECT_EQ(led.fg_color(), led2.fg_color());
     EXPECT_EQ(led.bg_color(), led2.bg_color());

tests/UI_slider.cpp

@@ -4,7 +4,8 @@ TEST(UI_slider, to_from_json)
 {
     UI_slider slider("slider_text", Color(255, 255, 255), Color(0, 0, 0), 0, 100, 50, nullptr);
     json j = slider.to_json(0);
-    UI_slider slider2(j);
+    UI_slider slider2;
+    slider2.from_json(j);
     EXPECT_EQ(slider.text(), slider2.text());
     EXPECT_EQ(slider.fg_color(), slider2.fg_color());
     EXPECT_EQ(slider.bg_color(), slider2.bg_color());

tests/UI_textbox.cpp

@@ -4,7 +4,8 @@ TEST(UI_textbox, to_from_json)
 {
     UI_textbox textbox("hint", Color(0, 0, 0), Color(255, 255, 255));
     json j = textbox.to_json(0);
-    UI_textbox textbox2(j);
+    UI_textbox textbox2;
+    textbox2.from_json(j);
     EXPECT_EQ(textbox.text(), textbox2.text());
     EXPECT_EQ(textbox.fg_color(), textbox2.fg_color());
     EXPECT_EQ(textbox.bg_color(), textbox2.bg_color());

tests/UI_thermo.cpp

@@ -4,7 +4,8 @@ TEST(UI_thermo, to_from_json)
 {
     UI_thermo thermo("thermo_text", Color(255, 255, 255), Color(0, 0, 0), 0, 100, 50);
     json j = thermo.to_json(0);
-    UI_thermo thermo2(j);
+    UI_thermo thermo2;
+    thermo2.from_json(j);
     EXPECT_EQ(thermo.text(), thermo2.text());
     EXPECT_EQ(thermo.fg_color(), thermo2.fg_color());
     EXPECT_EQ(thermo.bg_color(), thermo2.bg_color());