diff --git a/tests/CMakeLists.txt b/tests/CMakeLists.txt
index bfed2ae..a3e8cd1 100644
--- a/tests/CMakeLists.txt
+++ b/tests/CMakeLists.txt
@@ -1,6 +1,6 @@
 # Third Party
 find_package(GTest QUIET)
-find_package(Qt6 REQUIRED COMPONENTS Core)
+find_package(Qt6 REQUIRED COMPONENTS Core Test)
 set(CMAKE_AUTOUIC ON)
 set(CMAKE_AUTOMOC ON)
 set(CMAKE_AUTORCC ON)
@@ -23,6 +23,7 @@ if (GTest_FOUND)
         magic_enum::magic_enum
         GTest::gtest_main
         Qt::Core
+        Qt::Test
     )
 
     target_include_directories(tests
diff --git a/tests/Test.hpp b/tests/Test.hpp
index 5be6cc5..b2b1ca0 100644
--- a/tests/Test.hpp
+++ b/tests/Test.hpp
@@ -1,5 +1,4 @@
 #include "ui.hpp"
 #include "gtest/gtest.h"
+#include <QSignalSpy>
 #include <iostream>
-
-#define UNUSED(x) (void)(x)
diff --git a/tests/UI_button.cpp b/tests/UI_button.cpp
index 3ea2636..8884e1a 100644
--- a/tests/UI_button.cpp
+++ b/tests/UI_button.cpp
@@ -10,3 +10,11 @@ TEST(UI_button, to_from_json)
     EXPECT_EQ(button.fg_color(), button2.fg_color());
     EXPECT_EQ(button.bg_color(), button2.bg_color());
 }
+
+TEST(UI_button, signal)
+{
+    UI_button button("button_text", Color::Default, Color::Default);
+    QSignalSpy spy(&button, &UI_button::clicked);
+    button.click();
+    EXPECT_EQ(spy.count(), 1);
+}
diff --git a/tests/UI_checkbox.cpp b/tests/UI_checkbox.cpp
index 1106460..fd1a067 100644
--- a/tests/UI_checkbox.cpp
+++ b/tests/UI_checkbox.cpp
@@ -11,3 +11,11 @@ TEST(UI_checkbox, to_from_json)
     EXPECT_EQ(checkbox.bg_color(), checkbox2.bg_color());
     EXPECT_EQ(checkbox.state(), checkbox2.state());
 }
+
+TEST(UI_checkbox, signal)
+{
+    UI_checkbox checkbox("checkbox_text", Color::Default, Color::Default);
+    QSignalSpy spy(&checkbox, &UI_checkbox::changed);
+    checkbox.click();
+    EXPECT_EQ(spy.count(), 1);
+}
diff --git a/tests/UI_combobox.cpp b/tests/UI_combobox.cpp
index be4d848..757e7a0 100644
--- a/tests/UI_combobox.cpp
+++ b/tests/UI_combobox.cpp
@@ -11,3 +11,11 @@ TEST(UI_combobox, to_from_json)
     EXPECT_EQ(combobox.bg_color(), combobox2.bg_color());
     EXPECT_EQ(combobox.selected(), combobox2.selected());
 }
+
+TEST(UI_combobox, signal)
+{
+    UI_combobox combobox(Color::Default, Color::Default, {"option1", "option2"});
+    QSignalSpy spy(&combobox, &UI_combobox::changed);
+    combobox.set_selected(1);
+    EXPECT_EQ(spy.count(), 1);
+}
diff --git a/tests/UI_dial.cpp b/tests/UI_dial.cpp
index f91a104..6706034 100644
--- a/tests/UI_dial.cpp
+++ b/tests/UI_dial.cpp
@@ -16,8 +16,10 @@ TEST(UI_dial, to_from_json)
 TEST(UI_dial, set_value)
 {
     UI_dial dial("slider_text", Color(255, 255, 255), Color(0, 0, 0), 0, 100, 50);
+    QSignalSpy spy(&dial, &UI_dial::ui_changed);
     dial.set_value(75);
     EXPECT_EQ(dial.value(), 75);
+    EXPECT_EQ(spy.count(), 1);
 }
 
 TEST(UI_dial, unit)
diff --git a/tests/UI_item.cpp b/tests/UI_item.cpp
index 371e8f8..399b3e1 100644
--- a/tests/UI_item.cpp
+++ b/tests/UI_item.cpp
@@ -63,3 +63,16 @@ TEST(UI_item, to_json)
     EXPECT_EQ(j.at("fg_color"), Color(255, 255, 255).to_hex());
     EXPECT_EQ(j.at("bg_color"), Color(0, 0, 0).to_hex());
 }
+
+TEST(UI_item, signal)
+{
+    UI_item item("item", "item_text", Color(255, 255, 255), Color(0, 0, 0));
+    QSignalSpy spy(&item, &UI_item::ui_changed);
+    item.set_text("text");
+    item.append_text(" ");
+    item.set_bg_color(Color::Default);
+    item.set_fg_color(Color::Default);
+    item.set_enabled(0);
+    item.set_visible(0);
+    EXPECT_EQ(spy.count(), 6);
+}
diff --git a/tests/UI_slider.cpp b/tests/UI_slider.cpp
index 9fb34ea..923a80d 100644
--- a/tests/UI_slider.cpp
+++ b/tests/UI_slider.cpp
@@ -15,5 +15,10 @@ TEST(UI_slider, to_from_json)
 TEST(UI_slider, value)
 {
     UI_slider slider("slider_text", Color(255, 255, 255), Color(0, 0, 0), 0, 100, 50);
+    QSignalSpy spy_ui(&slider, &UI_slider::ui_changed);
+    QSignalSpy spy_value(&slider, &UI_slider::changed);
     EXPECT_EQ(slider.value(), 50);
+    slider.set_value(10);
+    EXPECT_EQ(spy_ui.count(), 1);
+    EXPECT_EQ(spy_value.count(), 1);
 }
diff --git a/tests/UI_textbox.cpp b/tests/UI_textbox.cpp
index fc4c65a..a2b9cb3 100644
--- a/tests/UI_textbox.cpp
+++ b/tests/UI_textbox.cpp
@@ -15,7 +15,21 @@ TEST(UI_textbox, to_from_json)
 TEST(UI_textbox, set_text)
 {
     UI_textbox textbox("hint", Color(0, 0, 0), Color(255, 255, 255));
+    QSignalSpy spy_ui(&textbox, &UI_textbox::ui_changed);
+    QSignalSpy spy_value(&textbox, &UI_textbox::changed);
     EXPECT_EQ(textbox.text(), "");
     textbox.set_text("random text");
     EXPECT_EQ(textbox.text(), "random text");
-}
\ No newline at end of file
+    EXPECT_GE(spy_ui.count(), 0);
+    EXPECT_GE(spy_value.count(), 0);
+}
+
+TEST(UI_textbox, set_hint)
+{
+    UI_textbox textbox("hint", Color(0, 0, 0), Color(255, 255, 255));
+    QSignalSpy spy_ui(&textbox, &UI_textbox::ui_changed);
+    EXPECT_EQ(textbox.hint(), "hint");
+    textbox.set_hint("random text");
+    EXPECT_EQ(textbox.hint(), "random text");
+    EXPECT_EQ(spy_ui.count(), 1);
+}
diff --git a/tests/UI_thermo.cpp b/tests/UI_thermo.cpp
index b23703f..1a7511b 100644
--- a/tests/UI_thermo.cpp
+++ b/tests/UI_thermo.cpp
@@ -15,6 +15,8 @@ TEST(UI_thermo, to_from_json)
 TEST(UI_thermo, set_value)
 {
     UI_thermo thermo("thermo_text", Color(255, 255, 255), Color(0, 0, 0), 0, 100, 50);
+    QSignalSpy spy(&thermo, &UI_thermo::ui_changed);
     thermo.set_value(75);
     EXPECT_EQ(thermo.value(), 75);
+    EXPECT_EQ(spy.count(), 1);
 }