新增: 壁纸切换（主题/本地图片/Bing/纯色渐变）

dialog.go

@@ -0,0 +1,119 @@
+package main
+
+import (
+	"fmt"
+	"unicode/utf16"
+	"unsafe"
+
+	"golang.org/x/sys/windows"
+)
+
+var (
+	comdlg32             = windows.NewLazySystemDLL("comdlg32.dll")
+	procGetOpenFileNameW  = comdlg32.NewProc("GetOpenFileNameW")
+	procChooseColorW      = comdlg32.NewProc("ChooseColorW")
+)
+
+func slicePtr(s interface{}) uintptr {
+	switch v := s.(type) {
+	case []uint16:
+		if len(v) == 0 { return 0 }
+		return uintptr(unsafe.Pointer(&v[0]))
+	case []uint32:
+		if len(v) == 0 { return 0 }
+		return uintptr(unsafe.Pointer(&v[0]))
+	}
+	return 0
+}
+
+func openFileDialog(owner uintptr) string {
+	type openFileName struct {
+		lStructSize       uint32
+		hwndOwner         uintptr
+		hInstance         uintptr
+		lpstrFilter       uintptr
+		lpstrCustomFilter uintptr
+		nMaxCustFilter    uint32
+		nFilterIndex      uint32
+		lpstrFile         uintptr
+		nMaxFile          uint32
+		lpstrFileTitle    uintptr
+		nMaxFileTitle     uint32
+		lpstrInitialDir   uintptr
+		lpstrTitle        uintptr
+		Flags             uint32
+		nFileOffset       uint16
+		nFileExtension    uint16
+		lpstrDefExt       uintptr
+		lCustData         uintptr
+		lpfnHook          uintptr
+		lpTemplateName    uintptr
+		pvReserved        uintptr
+		dwReserved        uint32
+		FlagsEx           uint32
+	}
+
+	// Filter: "Images\0*.jpg;*.png\0All\0*.*\0\0"
+	filterStr := "图片文件\x00*.jpg;*.jpeg;*.png;*.bmp;*.webp;*.gif\x00所有文件\x00*.*\x00\x00"
+	filterUTF16 := utf16.Encode([]rune(filterStr))
+
+	titleUTF16 := utf16.Encode([]rune("选择壁纸图片"))
+	fileBuf := make([]uint16, 260)
+
+	ofn := openFileName{
+		lStructSize: uint32(unsafe.Sizeof(openFileName{})),
+		hwndOwner:   owner,
+		lpstrFilter: slicePtr(filterUTF16),
+		lpstrFile:   slicePtr(fileBuf),
+		nMaxFile:    260,
+		lpstrTitle:  slicePtr(titleUTF16),
+		Flags:       0x00001000 | 0x00000800 | 0x00000004,
+	}
+
+	ret, _, _ := procGetOpenFileNameW.Call(uintptr(unsafe.Pointer(&ofn)))
+	if ret == 0 {
+		return ""
+	}
+	return windows.UTF16ToString(fileBuf)
+}
+
+func colorPickerDialog(owner uintptr, initialColor string) string {
+	type chooseColor struct {
+		lStructSize    uint32
+		hwndOwner      uintptr
+		hInstance      uintptr
+		rgbResult      uint32
+		lpCustColors   uintptr
+		Flags          uint32
+		lCustData      uintptr
+		lpfnHook       uintptr
+		lpTemplateName uintptr
+	}
+
+	custColors := make([]uint32, 16)
+
+	var initRGB uint32
+	if len(initialColor) > 4 && initialColor[0] == '#' {
+		var r, g, b uint32
+		fmt.Sscanf(initialColor[1:], "%02x%02x%02x", &r, &g, &b)
+		initRGB = r | (g << 8) | (b << 16)
+	}
+
+	cc := chooseColor{
+		lStructSize:  uint32(unsafe.Sizeof(chooseColor{})),
+		hwndOwner:    owner,
+		rgbResult:    initRGB,
+		lpCustColors: slicePtr(custColors),
+		Flags:        0x00000002,
+	}
+
+	ret, _, _ := procChooseColorW.Call(uintptr(unsafe.Pointer(&cc)))
+	if ret == 0 {
+		return ""
+	}
+
+	r := cc.rgbResult & 0xFF
+	g := (cc.rgbResult >> 8) & 0xFF
+	b := (cc.rgbResult >> 16) & 0xFF
+	return fmt.Sprintf("#%02x%02x%02x", r, g, b)
+}