🚧 InputText: Tweak ImGuiInputTextFlags_EscapeClearsAll handling so de…

…cision is taken on input buffer + Showcase a few more InputText() flags. (#5688, #2620)

               This makes is more obvious that value_change==true when apply_new_text != NULL.

core/src/main/kotlin/imgui/demo/ShowDemoWindowWidgets.kt

@@ -131,6 +131,7 @@ import imgui.ImGui.treeNodeToLabelSpacing
 import imgui.ImGui.treePop
 import imgui.ImGui.unindent
 import imgui.ImGui.windowDrawList
+import imgui.InputTextFlag
 import imgui.api.*
 import imgui.api.demoDebugInformations.Companion.helpMarker
 import imgui.classes.Color
@@ -1065,6 +1066,8 @@ object ShowDemoWindowWidgets {
         var buf2 = ByteArray(64)
         var buf3 = ByteArray(64)
         var editCount = 0
+        val buf4 = ByteArray(16)
+        var flags1: InputTextSingleFlags = InputTextFlag.EscapeClearsAll
         operator fun invoke() {
             // To wire InputText() with std::string or any other custom string type,
             // see the "Text Input > Resize Callback" section of this demo, and the misc/cpp/imgui_stdlib.h file.
@@ -1125,6 +1128,14 @@ object ShowDemoWindowWidgets {
                     Funcs2.MyInputTextMultiline("##MyStr", myStr, Vec2(-Float.MIN_VALUE, textLineHeight * 16), none)
                     text("Data: ${myStr.hashCode()}\nSize: ${myStr.strlen()}\nCapacity: ${myStr.size}")
                 }
+
+//                IMGUI_DEMO_MARKER("Widgets/Text Input/Miscellaneous");
+                treeNode("Miscellaneous") {
+                    ImGui.checkboxFlags("ImGuiInputTextFlags_EscapeClearsAll", ::flags1, InputTextFlag.EscapeClearsAll)
+                    ImGui.checkboxFlags("ImGuiInputTextFlags_ReadOnly", ::flags1, InputTextFlag.ReadOnly)
+                    ImGui.checkboxFlags("ImGuiInputTextFlags_NoUndoRedo", ::flags1, InputTextFlag.NoUndoRedo)
+                    ImGui.inputText("Hello", buf1, flags1)
+                }
             }
         }
     }

core/src/main/kotlin/imgui/internal/api/inputText.kt

@@ -508,7 +508,7 @@ internal interface inputText {
                 }
                 isCancel ->
                     if (flags has Itf.EscapeClearsAll) {
-                        if (state.curLenA > 0)
+                        if (buf[0] != 0.b)
                             revertEdit = true
                         else {
                             renderCursor = false; renderSelection = false
@@ -576,9 +576,10 @@ internal interface inputText {
             if (revertEdit && !isReadOnly) {
                 if (flags has Itf.EscapeClearsAll) {
                     // Clear input
+                    assert(buf[0] != 0.b)
                     applyNewText = ByteArray(0)
                     applyNewTextLength = 0
-                    valueChanged /= buf[0] != 0.b
+                    valueChanged = true
                     val emptyString = CharArray(0)
                     state.replace(emptyString, 0)
                 } else if (buf.strcmp(state.initialTextA) != 0) {
@@ -606,9 +607,12 @@ internal interface inputText {
                 textStrToUtf8(state.textA, state.textW)
             }
 
-            // 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.
+            // 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).
+            // 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).
             val applyEditBackToUserBuffer = !revertEdit || (validated && flags hasnt Itf.EnterReturnsTrue)
             if (applyEditBackToUserBuffer) {
                 // Apply new value immediately - copy modified buffer back