InputText: added ImGuiInputTextFlags_EscapeClearsAll (#5688)

docs/CHANGELOG.txt

@@ -91,6 +91,8 @@ Other Changes:
   Enter keep the input active and select all text.
 - InputText: numerical fields automatically accept full-width characters (U+FF01..U+FF5E)
   by converting them to half-width (U+0021..U+007E).
+- InputText: added ImGuiInputTextFlags_EscapeClearsAll flag: first press on Escape clears
+  text if any, second press deactivate the InputText(). (#5688)
 - InputText: added support for shift+click style selection. (#5619) [@procedural]
 - InputText: clarified that callbacks cannot modify buffer when using the ReadOnly flag.
 - InputText: fixed minor one-frame selection glitch when reverting with Escape.

imgui.h

@@ -1007,6 +1007,7 @@ enum ImGuiInputTextFlags_
     ImGuiInputTextFlags_CharsScientific     = 1 << 17,  // Allow 0123456789.+-*/eE (Scientific notation input)
     ImGuiInputTextFlags_CallbackResize      = 1 << 18,  // Callback on buffer capacity changes request (beyond 'buf_size' parameter value), allowing the string to grow. Notify when the string wants to be resized (for string types which hold a cache of their Size). You will be provided a new BufSize in the callback and NEED to honor it. (see misc/cpp/imgui_stdlib.h for an example of using this)
     ImGuiInputTextFlags_CallbackEdit        = 1 << 19,  // Callback on any edit (note that InputText() already returns true on edit, the callback is useful mainly to manipulate the underlying buffer while focus is active)
+    ImGuiInputTextFlags_EscapeClearsAll     = 1 << 20,  // Escape key clears content if not empty, and deactivate otherwise (constrast to default behavior of Escape to revert)
 
     // Obsolete names (will be removed soon)
 #ifndef IMGUI_DISABLE_OBSOLETE_FUNCTIONS

imgui_demo.cpp

@@ -8,11 +8,15 @@
 // Read imgui.cpp for more details, documentation and comments.
 // Get the latest version at https://github.com/ocornut/imgui
 
+// -------------------------------------------------
+// PLEASE DO NOT REMOVE THIS FILE FROM YOUR PROJECT!
+// -------------------------------------------------
 // Message to the person tempted to delete this file when integrating Dear ImGui into their codebase:
-// Do NOT remove this file from your project! Think again! It is the most useful reference code that you and other
+// Think again! It is the most useful reference code that you and other coders will want to refer to and call.
-// coders will want to refer to and call. Have the ImGui::ShowDemoWindow() function wired in an always-available
+// Have the ImGui::ShowDemoWindow() function wired in an always-available debug menu of your game/app!
-// debug menu of your game/app! Removing this file from your project is hindering access to documentation for everyone
+// Also include Metrics! ItemPicker! DebugLog! and other debug features.
-// in your team, likely leading you to poorer usage of the library.
+// Removing this file from your project is hindering access to documentation for everyone in your team,
+// likely leading you to poorer usage of the library.
 // Everything in this file will be stripped out by the linker if you don't call ImGui::ShowDemoWindow().
 // If you want to link core Dear ImGui in your shipped builds but want a thorough guarantee that the demo will not be
 // linked, you can setup your imconfig.h with #define IMGUI_DISABLE_DEMO_WINDOWS and those functions will be empty.
@@ -6718,7 +6722,7 @@ struct ExampleAppConsole
 
         // Command-line
         bool reclaim_focus = false;
-        ImGuiInputTextFlags input_text_flags = ImGuiInputTextFlags_EnterReturnsTrue | ImGuiInputTextFlags_CallbackCompletion | ImGuiInputTextFlags_CallbackHistory;
+        ImGuiInputTextFlags input_text_flags = ImGuiInputTextFlags_EnterReturnsTrue | ImGuiInputTextFlags_EscapeClearsAll | ImGuiInputTextFlags_CallbackCompletion | ImGuiInputTextFlags_CallbackHistory;
         if (ImGui::InputText("Input", InputBuf, IM_ARRAYSIZE(InputBuf), input_text_flags, &TextEditCallbackStub, (void*)this))
         {
             char* s = InputBuf;

imgui_widgets.cpp

@@ -4301,7 +4301,7 @@ bool ImGui::InputTextEx(const char* label, const char* hint, char* buf, int buf_
     }
 
     // Process other shortcuts/key-presses
-    bool cancel_edit = false;
+    bool revert_edit = false;
     if (g.ActiveId == id && !g.ActiveIdIsJustActivated && !clear_active_id)
     {
         IM_ASSERT(state != NULL);
@@ -4372,8 +4372,23 @@ bool ImGui::InputTextEx(const char* label, const char* hint, char* buf, int buf_
         }
         else if (is_cancel)
         {
-            clear_active_id = cancel_edit = true;
+            if (flags & ImGuiInputTextFlags_EscapeClearsAll)
+            {
+                if (state->CurLenA > 0)
+                {
+                    revert_edit = true;
+                }
+                else
+                {
                     render_cursor = render_selection = false;
+                    clear_active_id = true;
+                }
+            }
+            else
+            {
+                clear_active_id = revert_edit = true;
+                render_cursor = render_selection = false;
+            }
         }
         else if (is_undo || is_redo)
         {
@@ -4444,11 +4459,19 @@ bool ImGui::InputTextEx(const char* label, const char* hint, char* buf, int buf_
     if (g.ActiveId == id)
     {
         IM_ASSERT(state != NULL);
-        if (cancel_edit && !is_readonly)
+        if (revert_edit && !is_readonly)
+        {
+            if (flags & ImGuiInputTextFlags_EscapeClearsAll)
+            {
+                // Clear input
+                apply_new_text = "";
+                apply_new_text_length = 0;
+                STB_TEXTEDIT_CHARTYPE empty_string;
+                stb_textedit_replace(state, &state->Stb, &empty_string, 0);
+            }
+            else if (strcmp(buf, state->InitialTextA.Data) != 0)
             {
                 // Restore initial value. Only return true if restoring to the initial value changes the current buffer contents.
-            if (strcmp(buf, state->InitialTextA.Data) != 0)
-            {
                 // Push records into the undo stack so we can CTRL+Z the revert operation itself
                 apply_new_text = state->InitialTextA.Data;
                 apply_new_text_length = state->InitialTextA.Size - 1;
@@ -4473,7 +4496,7 @@ bool ImGui::InputTextEx(const char* label, const char* hint, char* buf, int buf_
         // When using 'ImGuiInputTextFlags_EnterReturnsTrue' as a special case we reapply the live buffer back to the input buffer before clearing ActiveId, even though strictly speaking it wasn't modified on this frame.
         // If we didn't do that, code like InputInt() with ImGuiInputTextFlags_EnterReturnsTrue would fail.
         // This also allows the user to use InputText() with ImGuiInputTextFlags_EnterReturnsTrue without maintaining any user-side storage (please note that if you use this property along ImGuiInputTextFlags_CallbackResize you can end up with your temporary string object unnecessarily allocating once a frame, either store your string data, either if you don't then don't use ImGuiInputTextFlags_CallbackResize).
-        const bool apply_edit_back_to_user_buffer = !cancel_edit || (validated && (flags & ImGuiInputTextFlags_EnterReturnsTrue) != 0);
+        const bool apply_edit_back_to_user_buffer = !revert_edit || (validated && (flags & ImGuiInputTextFlags_EnterReturnsTrue) != 0);
         if (apply_edit_back_to_user_buffer)
         {
             // Apply new value immediately - copy modified buffer back