Add InputTextResizable

src/hello_imgui/hello_imgui_widgets.h

@@ -3,7 +3,8 @@
 #include "imgui.h"
 #include <optional>
 #include <functional>
-
+#include <map>
+#include <variant>
 
 namespace HelloImGui
 {
@@ -13,6 +14,8 @@ namespace HelloImGui
 
     void EndGroupColumn();   // calls ImGui::EndGroup() + ImGui::SameLine()
 
+    // @@md#WidgetWithResizeHandle
+
     // WidgetWithResizeHandle: adds a resize handle to a widget
     // Example usage with ImPlot:
     //        void gui()
@@ -35,4 +38,52 @@ namespace HelloImGui
         std::optional<VoidFunction> onItemHovered = std::nullopt
         );
 
+    // @@md
+
+
+    // --------------------------------------------------------------------------------------------
+
+    // @@md#InputTextResizable
+
+    // `InputTextResizable`: displays a resizable text input widget
+    //
+    // The `InputTextResizable` widget allows you to create a text input field that can be resized by the user.
+    // It supports both single-line and multi-line text input.
+    // Note: the size of the widget is expressed in em units.
+    // **Usage example:**
+    //    C++:
+    //       ```cpp
+    //       // Somewhere in the application state
+    //       (static) InputTextData textInput("My text", true, ImVec2(10, 3));
+    //       // In the GUI function
+    //       bool changed = InputTextResizable("Label", &textInput);
+    //       ```
+    //    Python:
+    //       ```python
+    //       # Somewhere in the application state
+    //       text_input = hello_imgui.InputTextData("My text", multiline=True, size_em=ImVec2(10, 3))
+    //       # In the GUI function
+    //       changed, text_input = hello_imgui.InputTextResizable("Label", text_input)
+    //       ```
+    struct InputTextData
+    {
+        std::string Text;
+        bool Multiline = false;
+        ImVec2 SizeEm = ImVec2(0, 0);
+
+        InputTextData(const std::string& text = "", bool multiline = false, ImVec2 size_em = ImVec2(0, 0)) : Text(text), Multiline(multiline), SizeEm(size_em) {}
+    };
+    bool InputTextResizable(const char* label, InputTextData* textInput);
+
+    // Serialization for InputTextData
+    // -------------------------------
+    // to/from dict
+    using DictTypeInputTextData = std::map<std::string, std::variant<std::string, bool, float>>;
+    DictTypeInputTextData InputTextDataToDict(const InputTextData& data);
+    InputTextData InputTextDataFromDict(const DictTypeInputTextData& dict);
+    // to/from string
+    std::string InputTextDataToString(const InputTextData& data);
+    InputTextData InputTextDataFromString(const std::string& str);
+
+    // @@md
 }

src/hello_imgui/impl/hello_imgui_widgets.cpp

@@ -1,7 +1,10 @@
 #define IMGUI_DEFINE_MATH_OPERATORS
 #include "hello_imgui/hello_imgui_widgets.h"
+#include "hello_imgui/dpi_aware.h"
 #include "imgui.h"
+#include "imgui_stdlib.h"
 #include "imgui_internal.h"
+#include "nlohmann/json.hpp"
 
 #include <unordered_map>
 
@@ -57,7 +60,6 @@ namespace HelloImGui
                 onItemHovered.value()();
         }
 
-
         float em = ImGui::GetFontSize(), size = em * handleSizeEm;
         ImVec2 widget_bottom_right = ImGui::GetItemRectMax();
 
@@ -82,19 +84,26 @@ namespace HelloImGui
         // Color
         ImU32 color = ImGui::GetColorU32(ImGuiCol_Button);
         if (ImGui::IsMouseHoveringRect(zone.Min, zone.Max))
+        {
+            ImGui::SetMouseCursor(ImGuiMouseCursor_ResizeNWSE);
             color = ImGui::GetColorU32(ImGuiCol_ButtonHovered);
+        }
         if (resizingState->Resizing)
+        {
+            ImGui::SetMouseCursor(ImGuiMouseCursor_ResizeNWSE);
             color = ImGui::GetColorU32(ImGuiCol_ButtonActive);
+        }
 
         ImGui::GetWindowDrawList()->AddTriangleFilled(br, bl, tr, color);
 
+        if (mouseInZoneBeforeAfter)
+
         if (!resizingState->Resizing)
         {
             if (wasMouseJustClicked && mouseInZoneBeforeAfter)
             {
                 if (onItemResized.has_value() && onItemResized)
                     onItemResized.value()();
-                ImGui::SetMouseCursor(ImGuiMouseCursor_ResizeNWSE);
                 resizingState->Resizing = true;
             }
         }
@@ -113,12 +122,113 @@ namespace HelloImGui
             }
             else
             {
-                ImGui::SetMouseCursor(ImGuiMouseCursor_Arrow);
                 resizingState->Resizing = false;
             }
         }
 
         return widget_size;
     }
 
-}
+
+    static void setDefaultSizeIfNone(InputTextData* textInput)
+    {
+        if (textInput->SizeEm.x == 0 && textInput->SizeEm.y == 0)
+        {
+            float defaultWidth = 15.f;
+            float defaultHeight = 5.f;
+            if (textInput->Multiline)
+                textInput->SizeEm = ImVec2(defaultWidth, defaultHeight);
+            else
+                textInput->SizeEm = ImVec2(defaultWidth, 0);
+        }
+    }
+
+    bool InputTextResizable(const char* label, InputTextData* textInput)
+    {
+        setDefaultSizeIfNone(textInput);
+
+        static std::string hash_hash = "##";
+
+        bool labelIsHidden = (label[0] == '#' && label[1] == '#');
+        std::string inputLabel = labelIsHidden ? label : hash_hash + label;
+        std::string visibleLabel = labelIsHidden ? std::string(label).substr(2) : label;
+
+        bool changed = false;
+
+        auto gui_cb = [&]()
+        {
+            if (textInput->Multiline)
+            {
+                changed = ImGui::InputTextMultiline(inputLabel.c_str(), &textInput->Text, HelloImGui::EmToVec2(textInput->SizeEm));
+            }
+            else
+            {
+                ImGui::SetNextItemWidth(HelloImGui::EmSize(textInput->SizeEm.x));
+                changed = ImGui::InputText(inputLabel.c_str(), &textInput->Text);
+            }
+        };
+
+        ImVec2 newSizePixels = HelloImGui::WidgetWithResizeHandle(label, gui_cb, 0.8f);
+        ImVec2 newSize = HelloImGui::PixelsToEm(newSizePixels);
+        if (textInput->Multiline)
+            textInput->SizeEm = newSize;
+        else
+            textInput->SizeEm.x = newSize.x;
+
+        if (!labelIsHidden)
+        {
+            ImGui::SameLine();
+            ImGui::Text("%s", visibleLabel.c_str());
+        }
+
+        return changed;
+    }
+
+    // Serialization to/from dict
+    DictTypeInputTextData InputTextDataToDict(const InputTextData& data)
+    {
+        return {
+            {"Text", data.Text},
+            {"Multiline", data.Multiline},
+            {"SizeEm_x", data.SizeEm.x},
+            {"SizeEm_y", data.SizeEm.y}
+        };
+    }
+
+    InputTextData InputTextDataFromDict(const DictTypeInputTextData& dict)
+    {
+        InputTextData result;
+        if (dict.find("Text") != dict.end())
+            result.Text = std::get<std::string>(dict.at("Text"));
+        if (dict.find("Multiline") != dict.end())
+            result.Multiline = std::get<bool>(dict.at("Multiline"));
+        if (dict.find("SizeEm_x") != dict.end())
+            result.SizeEm.x = std::get<float>(dict.at("Size_x"));
+        if (dict.find("SizeEm_y") != dict.end())
+            result.SizeEm.y = std::get<float>(dict.at("Size_y"));
+        return result;
+    }
+
+    // Serialization to/from string using JSON
+    std::string InputTextDataToString(const InputTextData& data)
+    {
+        nlohmann::json j = {
+            {"Text", data.Text},
+            {"Multiline", data.Multiline},
+            {"SizeEm_x", data.SizeEm.x},
+            {"SizeEm_y", data.SizeEm.y}
+        };
+        return j.dump();
+    }
+
+    InputTextData InputTextDataFromString(const std::string& str)
+    {
+        nlohmann::json j = nlohmann::json::parse(str);
+        InputTextData result;
+        result.Text = j["Text"];
+        result.Multiline = j["Multiline"];
+        result.SizeEm.x = j["SizeEm_x"];
+        result.SizeEm.y = j["SizeEm_y"];
+        return result;
+    }
+}

src/hello_imgui_demos/hello_imgui_demodocking/hello_imgui_demodocking.main.cpp

@@ -15,6 +15,7 @@ It demonstrates how to:
 #include "hello_imgui/hello_imgui.h"
 #include "hello_imgui/renderer_backend_options.h"
 #include "hello_imgui/icons_font_awesome_6.h"
+#include "nlohmann/json.hpp"
 #include "imgui.h"
 #include "imgui_stdlib.h"
 #include "imgui_internal.h"
@@ -41,7 +42,12 @@ It demonstrates how to:
 //////////////////////////////////////////////////////////////////////////
 struct MyAppSettings
 {
-    std::string name = "Test";
+    HelloImGui::InputTextData motto = HelloImGui::InputTextData(
+        "Hello, Dear ImGui\n"
+        "Unleash your creativity!\n",
+        true, // multiline
+        ImVec2(14.f, 3.f) // initial size (in em)
+    );
     int value = 10;
 };
 
@@ -109,17 +115,25 @@ void LoadFonts(AppState& appState) // This is called by runnerParams.callbacks.L
 // Warning, the save/load function below are quite simplistic!
 std::string MyAppSettingsToString(const MyAppSettings& myAppSettings)
 {
-    std::stringstream ss;
-    ss << myAppSettings.name << "\n";
-    ss << myAppSettings.value;
-    return ss.str();
+    using namespace nlohmann;
+    json j;
+    j["motto"] = HelloImGui::InputTextDataToString(myAppSettings.motto);
+    j["value"] = myAppSettings.value;
+    return j.dump();
 }
 MyAppSettings StringToMyAppSettings(const std::string& s)
 {
-    std::stringstream ss(s);
     MyAppSettings myAppSettings;
-    ss >> myAppSettings.name;
-    ss >> myAppSettings.value;
+    using namespace nlohmann;
+    try {
+        json j = json::parse(s);
+        myAppSettings.motto = HelloImGui::InputTextDataFromString(j["motto"].get<std::string>());
+        myAppSettings.value = j["value"];
+    }
+    catch (json::exception& e)
+    {
+        HelloImGui::Log(HelloImGui::LogLevel::Error, "Error while parsing user settings: %s", e.what());
+    }
     return myAppSettings;
 }
 
@@ -215,13 +229,14 @@ void DemoUserSettings(AppState& appState)
     ImGui::PushFont(appState.TitleFont->font); ImGui::Text("User settings"); ImGui::PopFont();
     ImGui::BeginGroup();
     ImGui::SetNextItemWidth(HelloImGui::EmSize(7.f));
-    ImGui::InputText("Name", &appState.myAppSettings.name);
-    ImGui::SetNextItemWidth(HelloImGui::EmSize(7.f));
+
+
     ImGui::SliderInt("Value", &appState.myAppSettings.value, 0, 100);
+    HelloImGui::InputTextResizable("Motto", &appState.myAppSettings.motto);
+    ImGui::Text("(this text widget is resizable)");
     ImGui::EndGroup();
     if (ImGui::IsItemHovered())
         ImGui::SetTooltip("The values below are stored in the application settings ini file and restored at startup");
-
 }
 
 void DemoRocket(AppState& appState)