一直在使用react / redux应用程序,在此操作中,我一直把头撞在墙上.
问题-我正在使用wzywyg编辑器更新文件.当我上传照片时,应用程序会尝试在操作完成图像处理之前插入图像.因此,导致图片网址未定义.当我上传第二张图片时,将插入第一张图片,依此类推.
很明显,在调用下一个动作之前,thunk无法解析.
更多细节
>我的应用程序中有一个文本编辑器(summernote-react).用户上传图像时,onImageUpload会触发并触发handleImageUpload.
>从那里,我通过mapStatetoProps调度一个动作,并处理了图像以进行上传.
>处理完图像后,应返回编辑器并将图像路径嵌入编辑器中进行预览.
现在,在调度未定义,然后又不是函数的过程中,我遇到了相同的错误模式.我想念什么?
addUploadToDocument(...).then is not a function
Uncaught TypeError: Cannot read property 'then' of undefined
我可以确认以下几点:
-Redux-thunk已正确设置.它在我们的生产版本中正常运行.
-该动作正在从我的组件中调用.只是不确定是否调度.我可以成功上传图像,但是在解决操作之前会启动回调.
这是我的动作代码:
// actions.js
// thunk
export function loadImage(document, file) {
return (dispatch, getState) => {
return dispatch(addUploadToDocument(document, file))
.then(() => {
console.log('Thunk is loaded.. chyeah.');
var uploads = this.props.uploads
var image = uploads[uploads.length - 1]
ReactSummernote.insertImage(image.previewURL, $image => {
$image.css("width", Math.floor($image.width() / 2));
$image.attr("alt", image.name);
});
});
}
}
//image processing action
export function addUploadToDocument(document, file) {
return (dispatch, getState) => {
//const position = getState().bodyEditorSelection.index
const base64Reader = new FileReader()
base64Reader.addEventListener('load', function() {
const base64 = base64Reader.result.replace(/data:.*?base64,/, '')
const key = Math.random().toString(36).substring(7)
const destination_path = `/uploads/${document.name}/${key}-${file.name}`
return dispatch({
type: DOCUMENT_ADD_UPLOAD,
payload: {
path: destination_path,
type: file.type,
base64: base64,
name: document.name,
previewURL: window.URL.createObjectURL(file),
//position: position
}
})
})
base64Reader.readAsDataURL(file)
}
}
这是我的组件.
handleImageUpload (files, editor, welEditable) {
var file = files[files.length -1];
this.props.loadImage(this.props.document, file)
}
render() {
this.syncBodyEditorState()
this.state = this.state || {}
return (
<ReactSummernote
value={this.props.body}
options={{
height: 750,
dialogsInBody: true,
toolbar: [
["style", ["style"]],
["font", ["bold", "underline", "clear"]],
["fontname", ["fontname"]],
["para", ["ul", "ol", "paragraph"]],
["table", ["table"]],
["insert", ["link", "picture", "video"]],
["view", ["codeview"]]
]
}}
onImageUpload={this.handleImageUpload}
onChange={this.handleChange}
/>
)
}
}
function mapStateToProperties(state) {
const currentDocument = currentDocumentSelector(state).currentDocument
return {
document: currentDocument,
bodyEditorSelection: state.bodyEditorSelection,
body: currentDocument.content.body,
uploads: currentDocument.content.uploads
}
}
export default connect(mapStateToProperties, {
SummernoteEditor,
updateDocumentBody,
updateBodyEditorSelection,
addUploadToDocument,
loadImage
})(SummernoteEditor)
我错过了一些琐碎的事情吗?我看了几十个例子,笨拙让我难过!
先谢谢您的帮助.
解决方法:
现在,尽管您这样做了,您的addUploadToDocument函数仍未返回promise,然后使用了dispatch方法(它只是返回普通对象的thunk).如果需要继续操作,可以将addUploadToDocument函数的内容包装在Promise中,然后可以使用.这是一个有点不同的方法,需要一些折磨才能使您入门(假设“加载”事件只能发生一次):
export function loadImage(document, file) {
return (dispatch, getState) => {
const base64Reader = new FileReader();
const promise = new Promise((resolve, reject)=> {
base64Reader.addEventListener('load', resolve)
})
.then(()=> {
const base64 = base64Reader.result.replace(/data:.*?base64,/, '')
const key = Math.random().toString(36).substring(7)
const destination_path = `/uploads/${document.name}/${key}-${file.name}`
dispatch({
type: DOCUMENT_ADD_UPLOAD,
payload: {
path: destination_path,
type: file.type,
base64: base64,
name: document.name,
previewURL: window.URL.createObjectURL(file),
//position: position
}
})
})
.then(()=> {
console.log('Thunk is loaded.. chyeah.');
var uploads = this.props.uploads
var image = uploads[uploads.length - 1]
ReactSummernote.insertImage(image.previewURL, $image => {
$image.css("width", Math.floor($image.width() / 2));
$image.attr("alt", image.name);
});
})
base64Reader.readAsDataURL(file);
return promise;
}
}