rui_orig/imageView.go

447 lines
13 KiB
Go
Raw Blame History

This file contains ambiguous Unicode characters

This file contains Unicode characters that might be confused with other characters. If you think that this is intentional, you can safely ignore this warning. Use the Escape button to reveal them.

package rui
import (
"encoding/base64"
"fmt"
"path/filepath"
"runtime"
"strings"
)
const (
// LoadedEvent is the constant for the "loaded-event" property tag.
// The "loaded-event" event occurs event occurs when the image has been loaded.
LoadedEvent = "loaded-event"
// ErrorEvent is the constant for the "error-event" property tag.
// The "error-event" event occurs event occurs when the image loading failed.
ErrorEvent = "error-event"
// NoneFit - value of the "object-fit" property of an ImageView. The replaced content is not resized
NoneFit = 0
// ContainFit - value of the "object-fit" property of an ImageView. The replaced content
// is scaled to maintain its aspect ratio while fitting within the elements content box.
// The entire object is made to fill the box, while preserving its aspect ratio, so the object
// will be "letterboxed" if its aspect ratio does not match the aspect ratio of the box.
ContainFit = 1
// CoverFit - value of the "object-fit" property of an ImageView. The replaced content
// is sized to maintain its aspect ratio while filling the elements entire content box.
// If the object's aspect ratio does not match the aspect ratio of its box, then the object will be clipped to fit.
CoverFit = 2
// FillFit - value of the "object-fit" property of an ImageView. The replaced content is sized
// to fill the elements content box. The entire object will completely fill the box.
// If the object's aspect ratio does not match the aspect ratio of its box, then the object will be stretched to fit.
FillFit = 3
// ScaleDownFit - value of the "object-fit" property of an ImageView. The content is sized as
// if NoneFit or ContainFit were specified, whichever would result in a smaller concrete object size.
ScaleDownFit = 4
)
// ImageView - image View
type ImageView interface {
View
// NaturalSize returns the intrinsic, density-corrected size (width, height) of the image in pixels.
// If the image hasn't been loaded yet or an load error has occurred, then (0, 0) is returned.
NaturalSize() (float64, float64)
// CurrentSource() return the full URL of the image currently visible in the ImageView.
// If the image hasn't been loaded yet or an load error has occurred, then "" is returned.
CurrentSource() string
}
type imageViewData struct {
viewData
naturalWidth float64
naturalHeight float64
currentSrc string
}
// NewImageView create new ImageView object and return it
func NewImageView(session Session, params Params) ImageView {
view := new(imageViewData)
view.init(session)
setInitParams(view, params)
return view
}
func newImageView(session Session) View {
return NewImageView(session, nil)
}
// Init initialize fields of imageView by default values
func (imageView *imageViewData) init(session Session) {
imageView.viewData.init(session)
imageView.tag = "ImageView"
//imageView.systemClass = "ruiImageView"
}
func (imageView *imageViewData) String() string {
return getViewString(imageView)
}
func (imageView *imageViewData) normalizeTag(tag string) string {
tag = strings.ToLower(tag)
switch tag {
case "source":
tag = Source
case "src-set", "source-set":
tag = SrcSet
case VerticalAlign:
tag = ImageVerticalAlign
case HorizontalAlign:
tag = ImageHorizontalAlign
case altTag:
tag = AltText
}
return tag
}
func (imageView *imageViewData) Remove(tag string) {
imageView.remove(imageView.normalizeTag(tag))
}
func (imageView *imageViewData) remove(tag string) {
imageView.viewData.remove(tag)
if imageView.created {
switch tag {
case Source:
imageView.session.updateProperty(imageView.htmlID(), "src", "")
imageView.session.removeProperty(imageView.htmlID(), "srcset")
case AltText:
updateInnerHTML(imageView.htmlID(), imageView.session)
case ImageVerticalAlign, ImageHorizontalAlign:
updateCSSStyle(imageView.htmlID(), imageView.session)
}
}
}
func (imageView *imageViewData) Set(tag string, value any) bool {
return imageView.set(imageView.normalizeTag(tag), value)
}
func (imageView *imageViewData) set(tag string, value any) bool {
if value == nil {
imageView.remove(tag)
return true
}
switch tag {
case Source:
if text, ok := value.(string); ok {
imageView.properties[tag] = text
if imageView.created {
src, srcset := imageView.src(text)
imageView.session.updateProperty(imageView.htmlID(), "src", src)
if srcset != "" {
imageView.session.updateProperty(imageView.htmlID(), "srcset", srcset)
} else {
imageView.session.removeProperty(imageView.htmlID(), "srcset")
}
}
imageView.propertyChangedEvent(Source)
return true
}
notCompatibleType(Source, value)
case SrcSet:
if text, ok := value.(string); ok {
if text == "" {
delete(imageView.properties, tag)
} else {
imageView.properties[tag] = text
}
if imageView.created {
_, srcset := imageView.src(text)
if srcset != "" {
imageView.session.updateProperty(imageView.htmlID(), "srcset", srcset)
} else {
imageView.session.removeProperty(imageView.htmlID(), "srcset")
}
}
imageView.propertyChangedEvent(Source)
return true
}
notCompatibleType(Source, value)
case AltText:
if text, ok := value.(string); ok {
imageView.properties[AltText] = text
if imageView.created {
updateInnerHTML(imageView.htmlID(), imageView.session)
}
imageView.propertyChangedEvent(Source)
return true
}
notCompatibleType(tag, value)
case LoadedEvent, ErrorEvent:
if listeners, ok := valueToNoParamListeners[ImageView](value); ok {
if listeners == nil {
delete(imageView.properties, tag)
} else {
imageView.properties[tag] = listeners
}
return true
}
default:
if imageView.viewData.set(tag, value) {
if imageView.created {
switch tag {
case ImageVerticalAlign, ImageHorizontalAlign:
updateCSSStyle(imageView.htmlID(), imageView.session)
}
}
return true
}
}
return false
}
func (imageView *imageViewData) Get(tag string) any {
return imageView.viewData.get(imageView.normalizeTag(tag))
}
func (imageView *imageViewData) imageListeners(tag string) []func(ImageView) {
if value := imageView.getRaw(tag); value != nil {
if listeners, ok := value.([]func(ImageView)); ok {
return listeners
}
}
return []func(ImageView){}
}
func (imageView *imageViewData) srcSet(path string) string {
if value := imageView.getRaw(SrcSet); value != nil {
if text, ok := value.(string); ok {
srcset := strings.Split(text, ",")
buffer := allocStringBuilder()
defer freeStringBuilder(buffer)
for i, src := range srcset {
if i > 0 {
buffer.WriteString(", ")
}
src = strings.Trim(src, " \t\n")
buffer.WriteString(src)
if index := strings.LastIndex(src, "@"); index > 0 {
if ext := strings.LastIndex(src, "."); ext > index {
buffer.WriteRune(' ')
buffer.WriteString(src[index+1 : ext])
}
} else {
buffer.WriteString(" 1x")
}
}
return buffer.String()
}
}
if srcset, ok := resources.imageSrcSets[path]; ok {
buffer := allocStringBuilder()
defer freeStringBuilder(buffer)
for i, src := range srcset {
if i > 0 {
buffer.WriteString(", ")
}
buffer.WriteString(src.path)
buffer.WriteString(fmt.Sprintf(" %gx", src.scale))
}
return buffer.String()
}
return ""
}
func (imageView *imageViewData) htmlTag() string {
return "img"
}
func (imageView *imageViewData) src(src string) (string, string) {
if src != "" && src[0] == '@' {
if image, ok := imageView.Session().ImageConstant(src[1:]); ok {
src = image
} else {
src = ""
}
}
if src != "" {
srcset := imageView.srcSet(src)
if runtime.GOOS == "js" && wasmMediaResources {
if image, ok := resources.images[src]; ok && image.fs != nil {
dataType := map[string]string{
".svg": "data:image/svg+xml",
".png": "data:image/png",
".jpg": "data:image/jpg",
".jpeg": "data:image/jpg",
".gif": "data:image/gif",
}
ext := strings.ToLower(filepath.Ext(src))
if prefix, ok := dataType[ext]; ok {
if data, err := image.fs.ReadFile(image.path); err == nil {
return prefix + ";base64," + base64.StdEncoding.EncodeToString(data), ""
} else {
DebugLog(err.Error())
}
}
}
}
return src, srcset
}
return "", ""
}
func (imageView *imageViewData) htmlProperties(self View, buffer *strings.Builder) {
imageView.viewData.htmlProperties(self, buffer)
if imageResource, ok := imageProperty(imageView, Source, imageView.Session()); ok && imageResource != "" {
if src, srcset := imageView.src(imageResource); src != "" {
buffer.WriteString(` src="`)
buffer.WriteString(src)
buffer.WriteString(`"`)
if srcset != "" {
buffer.WriteString(` srcset="`)
buffer.WriteString(srcset)
buffer.WriteString(`"`)
}
}
}
if text := GetImageViewAltText(imageView); text != "" {
buffer.WriteString(` alt="`)
buffer.WriteString(text)
buffer.WriteString(`"`)
}
buffer.WriteString(` onload="imageLoaded(this, event)"`)
if len(imageView.imageListeners(ErrorEvent)) > 0 {
buffer.WriteString(` onerror="imageError(this, event)"`)
}
}
func (imageView *imageViewData) cssStyle(self View, builder cssBuilder) {
imageView.viewData.cssStyle(self, builder)
if value, ok := enumProperty(imageView, Fit, imageView.session, 0); ok {
builder.add("object-fit", enumProperties[Fit].cssValues[value])
} else {
builder.add("object-fit", "none")
}
vAlign := GetImageViewVerticalAlign(imageView)
hAlign := GetImageViewHorizontalAlign(imageView)
if vAlign != CenterAlign || hAlign != CenterAlign {
var position string
switch hAlign {
case LeftAlign:
position = "left"
case RightAlign:
position = "right"
default:
position = "center"
}
switch vAlign {
case TopAlign:
position += " top"
case BottomAlign:
position += " bottom"
default:
position += " center"
}
builder.add("object-position", position)
}
}
func (imageView *imageViewData) handleCommand(self View, command string, data DataObject) bool {
switch command {
case "imageViewError":
for _, listener := range imageView.imageListeners(ErrorEvent) {
listener(imageView)
}
case "imageViewLoaded":
imageView.naturalWidth = dataFloatProperty(data, "natural-width")
imageView.naturalHeight = dataFloatProperty(data, "natural-height")
imageView.currentSrc, _ = data.PropertyValue("current-src")
for _, listener := range imageView.imageListeners(LoadedEvent) {
listener(imageView)
}
default:
return imageView.viewData.handleCommand(self, command, data)
}
return true
}
func (imageView *imageViewData) NaturalSize() (float64, float64) {
return imageView.naturalWidth, imageView.naturalHeight
}
func (imageView *imageViewData) CurrentSource() string {
return imageView.currentSrc
}
// GetImageViewSource returns the image URL of an ImageView subview.
// If the second argument (subviewID) is not specified or it is "" then a left position of the first argument (view) is returned
func GetImageViewSource(view View, subviewID ...string) string {
if len(subviewID) > 0 && subviewID[0] != "" {
view = ViewByID(view, subviewID[0])
}
if view != nil {
if image, ok := imageProperty(view, Source, view.Session()); ok {
return image
}
}
return ""
}
// GetImageViewAltText returns an alternative text description of an ImageView subview.
// If the second argument (subviewID) is not specified or it is "" then a left position of the first argument (view) is returned
func GetImageViewAltText(view View, subviewID ...string) string {
if len(subviewID) > 0 && subviewID[0] != "" {
view = ViewByID(view, subviewID[0])
}
if view != nil {
if value := view.getRaw(AltText); value != nil {
if text, ok := value.(string); ok {
text, _ = view.Session().GetString(text)
return text
}
}
}
return ""
}
// GetImageViewFit returns how the content of a replaced ImageView subview:
// NoneFit (0), ContainFit (1), CoverFit (2), FillFit (3), or ScaleDownFit (4).
// If the second argument (subviewID) is not specified or it is "" then a left position of the first argument (view) is returned
func GetImageViewFit(view View, subviewID ...string) int {
return enumStyledProperty(view, subviewID, Fit, NoneFit, false)
}
// GetImageViewVerticalAlign return the vertical align of an ImageView subview: TopAlign (0), BottomAlign (1), CenterAlign (2)
// If the second argument (subviewID) is not specified or it is "" then a left position of the first argument (view) is returned
func GetImageViewVerticalAlign(view View, subviewID ...string) int {
return enumStyledProperty(view, subviewID, ImageVerticalAlign, LeftAlign, false)
}
// GetImageViewHorizontalAlign return the vertical align of an ImageView subview: LeftAlign (0), RightAlign (1), CenterAlign (2)
// If the second argument (subviewID) is not specified or it is "" then a left position of the first argument (view) is returned
func GetImageViewHorizontalAlign(view View, subviewID ...string) int {
return enumStyledProperty(view, subviewID, ImageHorizontalAlign, LeftAlign, false)
}