我的应用程序的一些背景知识:
后端-Python,烧瓶。该数据库当前只是嵌套的字典和列表
前端-React.js
我将参考的功能:
FetchPlayers()-使用fetch()从后端获取一个数组,其中包含所有玩家。它还使用setState()将播放器添加到状态。
EditPlayer(playerid)-使用fetch()POST请求后端更改一个播放器上的信息。
因此,当前用户启动页面时,将调用FetchPlayers()以获取将显示的播放器列表。用户还可以通过菜单编辑这些播放器信息。当用户确认编辑(通过按下按钮)时,应用程序首先调用EditPlayer(),然后在调用FetchPlayers()之后的一行中更新网页上的播放器列表。
问题是页面未使用新的编辑进行更新。对我来说,查看新的修改我必须重新加载页面。这表明FetchPlayers()是在EditPlayer()之前被调用的。有谁知道我该如何解决?
提前致谢!
编辑
edit_player(_playerid, _newfirstname, _newlastname, _newclass) {
fetch('http://' + Globals.BaseIP + Globals.PortForBackend + '/api/editplayer', {
//Options for the fetch request
method:'POST',
headers: {
//Header objects
'Accept':'application/json, text/plain, */*',
'Content-type':'application/json'
},
body:JSON.stringify({UserID:UserServiceLocal.UserID(), token:UserServiceLocal.token(), GameID:this.props.gameID, PlayerID:_playerid, Firstname:_newfirstname, Lastname:_newlastname, Class:_newclass}),
mode:'cors'
})
.catch((error) => console.log(error));
}
FetchPlayers的代码
FetchPlayers () {
fetch('http://' + Globals.BaseIP + Globals.PortForBackend + '/api/fetchplayers', {
//Options for the fetch request
method:'POST',
headers: {
//Header objects
'Accept':'application/json, text/plain, */*',
'Content-type':'application/json'
},
body:JSON.stringify({UserID:UserServiceLocal.UserID(), token:UserServiceLocal.token(), GameID:this.props.gameID}),
mode:'cors'
})
.then((res) => res.json())
.then((data) => this.parse_fetch_players_response(data))
.catch((error) => console.log(error))
}
parse_fetch_players_response(data) {
console.log(data['players']);
this.setState({Playerlist:data['players']});
this.ListScrollToBottom();
}
确认编辑时运行的代码
Btn_EditPlayer() {
this.edit_player(this.state.playereditID, this.state.playereditName,
this.state.playereditLastname, this.state.playereditClass);
this.FetchPlayers();
渲染功能:
return (
<div className="PageFooter" onKeyPress={(event) => this.EnterKeyPress_EditPlayer(event)}>
<Textinput className="FirstNameTextbox" id="playereditName" label="First name" value={this.state.playereditName} onChange={this.textinput_handleChange}/>
<Textinput className="LastNameTextbox" id="playereditLastname" label="Last name" value={this.state.playereditLastname} onChange={this.textinput_handleChange}/>
<Textinput className="ClassTextbox" id="playereditClass" label="Class" value={this.state.playereditClass} onChange={this.textinput_handleChange}/>
<button id='editPlayerButton' className="mdc-button mdc-button--unelevated mdl-button--colored mdc-ripple-surface" onClick={() => this.Btn_EditPlayer()}>Edit Player</button>
<button id="cancel-edit-player-btn" className="mdc-button mdc-button--raised mdl-button--colored mdc-ripple-surface" onClick={() => this.EditPlayer_Cancel_Btn()}>Cancel</button>
</div>
);
列表元素渲染功能:
return (
<div>
<ul className="mdc-list" id="list-container" >
<li role="separator" className="mdc-list-divider"></li>
<li className="mdc-list-item" >
<span className="mdc-list-item__text list_text_firstname">
<b>Firstname</b>
</span>
<span className="mdc-list-item__text list_text_lastname">
<b>Lastname</b>
</span>
<span className="mdc-list-item__text list_text_class">
<b>Class</b>
</span>
<span className="mdc-list-item__graphic" role="presentation">
<i className="material-icons list_edit_icon">edit</i>
<i className="material-icons list_remove_icon">delete</i>
</span>
</li>
<li role="separator" className="mdc-list-divider"></li>
<ListEntry ListItemCSS="selected-list-entry" firstname="This is above" lastname="Butter" class="Jelly" id="1" delete_self={(playerID) => this.delete_item(playerID)} edit_button_clicked={(playerID) => this.Edit_Button_Clicked(playerID)}/>
<ListEntry firstname="Peanut" lastname="Butter" class="Jelly" id="1" delete_self={(playerID) => this.delete_item(playerID)} edit_button_clicked={(playerID) => this.Edit_Button_Clicked(playerID)}/>
{playerListItems}
</ul>
</div>
);
最佳答案
尝试从this.FetchPlayers()
中删除Btn_EditPlayer()
并将其添加为edit_player
的回调,如下所示:
this.edit_player(this.state.playereditID, this.state.playereditName,
this.state.playereditLastname, this.state.playereditClass, this.FetchPlayers);
edit_player(_playerid, _newfirstname, _newlastname, _newclass, callBack) {
fetch('http://' + Globals.BaseIP + Globals.PortForBackend + '/api/editplayer', {
//Options for the fetch request
method:'POST',
headers: {
//Header objects
'Accept':'application/json, text/plain, */*',
'Content-type':'application/json'
},
body:JSON.stringify({UserID:UserServiceLocal.UserID(), token:UserServiceLocal.token(), GameID:this.props.gameID, PlayerID:_playerid, Firstname:_newfirstname, Lastname:_newlastname, Class:_newclass}),
mode:'cors'
}).then((res) => {
// run your callback (fetchPlayers in this case) only when we know the update is done.
callBack()
}).catch((error) => console.log(error));
}
编辑(错字)
关于javascript - ReactJS-在fetch()完成之前运行的明显代码,我们在Stack Overflow上找到一个类似的问题:https://stackoverflow.com/questions/50301071/