Break raygui.go into separate files

- per-control .go file,
- separate file for style/property stuff,
- added NumProperties enum to the list of properties for constraint checking,
- should be no code changes

raygui/combobox.go

@@ -0,0 +1,102 @@
+package raygui
+
+import (
+	"fmt"
+	"github.com/gen2brain/raylib-go/raylib"
+)
+
+// ComboBox draws a simplified version of a ComboBox allowing the user to select a string
+// from a list accompanied by an N/M counter. The widget does not provide a drop-down/completion
+// or any input support.
+func ComboBox(bounds rl.Rectangle, comboText []string, active int) int {
+	// Reject invalid selections and disable rendering.
+	comboCount := len(comboText)
+	if active < 0 || active >= comboCount {
+		rl.TraceLog(rl.LogWarning, "ComboBox active expects 0 <= active <= %d", comboCount)
+		return -1
+	}
+
+	activeText := comboText[active]
+
+	// style sizing.
+	textHeight := int32(style[GlobalTextFontsize])
+	textWidth := rl.MeasureText(activeText, textHeight)
+	borderWidth := int32(style[ComboboxBorderWidth])
+	textPadding := int32(style[ToggleTextPadding])
+
+	b := bounds.ToInt32()
+	if b.Width < textWidth {
+		b.Width = textWidth + textPadding
+		bounds.Width = float32(b.Width)
+	}
+	if b.Height < textHeight {
+		b.Height = textHeight + textPadding
+		bounds.Height = float32(b.Height)
+	}
+
+	// Identify what the counter is going to look like with max digits so we don't resize it.
+	clickWidth := rl.MeasureText(fmt.Sprintf("%d/%d", comboCount, comboCount), b.Height)
+
+	click := rl.NewRectangle(bounds.X+bounds.Width+float32(style[ComboboxPadding]), bounds.Y, float32(clickWidth), float32(b.Height))
+	c := click.ToInt32()
+	mousePoint := rl.GetMousePosition()
+	state := Normal
+	if rl.CheckCollisionPointRec(mousePoint, bounds) || rl.CheckCollisionPointRec(mousePoint, click) {
+		if rl.IsMouseButtonDown(rl.MouseLeftButton) {
+			state = Pressed
+		} else if rl.IsMouseButtonReleased(rl.MouseLeftButton) || rl.IsMouseButtonPressed(rl.MouseLeftButton) {
+			state = Pressed
+		} else {
+			state = Focused
+		}
+	}
+
+	// Draw control
+	var borderColor, insideColor, listColor, textColor rl.Color
+
+	switch state {
+	case Normal:
+		borderColor = rl.GetColor(int32(style[ComboboxDefaultBorderColor]))
+		insideColor = rl.GetColor(int32(style[ComboboxDefaultInsideColor]))
+		listColor = rl.GetColor(int32(style[ComboboxDefaultListTextColor]))
+		textColor = rl.GetColor(int32(style[ComboboxDefaultTextColor]))
+
+	case Focused:
+		borderColor = rl.GetColor(int32(style[ComboboxHoverBorderColor]))
+		insideColor = rl.GetColor(int32(style[ComboboxHoverInsideColor]))
+		listColor = rl.GetColor(int32(style[ComboboxHoverListTextColor]))
+		textColor = rl.GetColor(int32(style[ComboboxHoverTextColor]))
+
+	case Pressed:
+		borderColor = rl.GetColor(int32(style[ComboboxPressedBorderColor]))
+		insideColor = rl.GetColor(int32(style[ComboboxPressedInsideColor]))
+		listColor = rl.GetColor(int32(style[ComboboxPressedListTextColor]))
+		textColor = rl.GetColor(int32(style[ComboboxPressedTextColor]))
+
+	default:
+		rl.TraceLog(rl.LogWarning, "ComboBox in unrecognized state %d", state)
+		return -1
+	}
+
+	// Render the box itself
+	rl.DrawRectangle(b.X, b.Y, b.Width, b.Height, borderColor)
+	rl.DrawRectangle(b.X+borderWidth, b.Y+borderWidth, b.Width-(2*borderWidth), b.Height-(2*borderWidth), insideColor)
+	rl.DrawText(activeText, b.X+((b.Width/2)-(rl.MeasureText(activeText, textHeight)/2)), b.Y+((b.Height/2)-(textHeight/2)), textHeight, textColor)
+
+	// Render the accompanying "clicks" box showing the element counter.
+	rl.DrawRectangle(c.X, c.Y, c.Width, c.Height, borderColor)
+	rl.DrawRectangle(c.X+borderWidth, c.Y+borderWidth, c.Width-(2*borderWidth), c.Height-(2*borderWidth), insideColor)
+	companionText := fmt.Sprintf("%d/%d", active+1, comboCount)
+	rl.DrawText(companionText, c.X+((c.Width/2)-(rl.MeasureText(companionText, textHeight)/2)), c.Y+((c.Height/2)-(textHeight/2)), textHeight, listColor)
+
+	if rl.CheckCollisionPointRec(mousePoint, bounds) || rl.CheckCollisionPointRec(mousePoint, click) {
+		if rl.IsMouseButtonPressed(rl.MouseLeftButton) {
+			active++
+			if active >= comboCount {
+				active = 0
+			}
+		}
+	}
+
+	return active
+}