目标是为动态数据集使用缓冲存储。工作流程如下：
- 服务器上已经存在一些数据。
- 客户端使用缓冲存储和无限网格来处理数据。
- 当应用程序运行时，存储正在加载，并且“加载”事件将网格滚动到最后一条消息。
- 一些记录被添加到服务器。
- 客户端收到推送通知并运行商店重新加载。topic.store.load({addRecords: true});
- load 事件运行并尝试再次滚动到最后一条消息但失败：
TypeError: offsetsTo is null e = Ext.fly(offsetsTo.el || offsetsTo, '_internal').getXY();
似乎网格视图没有刷新，也没有显示添加的记录，只有它们所在位置的空白。任何想法如何使网格视图正确刷新？
商店初始化：
Ext.define('orm.data.Store', {
extend: 'Ext.data.Store',
requires: ['orm.data.writer.Writer'],
constructor: function (config) {
Ext.apply(this, config);
this.proxy = Ext.merge(this.proxy, {
type: 'rest',
batchActions: true,
reader: {
type: 'json',
root: 'rows'
},
writer: {
type: 'orm'
}
});
this.callParent(arguments);
}
});
Ext.define('akma.chat.model.ChatMessage', {
extend:'Ext.data.Model',
fields:[
{ name:'id', type:'int', defaultValue : undefined },
{ name:'createDate', type:'date', dateFormat:'Y-m-d\\TH:i:s', defaultValue : undefined },
{ name:'creator', type:'User', isManyToOne : true, defaultValue : undefined },
{ name:'message', type:'string', defaultValue : undefined },
{ name:'nameFrom', type:'string', defaultValue : undefined },
{ name:'topic', type:'Topic', isManyToOne : true, defaultValue : undefined }
],
idProperty: 'id'
});
Ext.define('akma.chat.store.ChatMessages', {
extend: 'orm.data.Store',
requires: ['orm.data.Store'],
alias: 'store.akma.chat.store.ChatMessages',
storeId: 'ChatMessages',
model: 'akma.chat.model.ChatMessage',
proxy: {
url: 'http://localhost:8080/chat/services/entities/chatmessage'
}
});
var store = Ext.create('akma.chat.store.ChatMessages', {
buffered: true,
pageSize: 10,
trailingBufferZone: 5,
leadingBufferZone: 5,
purgePageCount: 0,
scrollToLoadBuffer: 10,
autoLoad: false,
sorters: [
{
property: 'id',
direction: 'ASC'
}
]
});
网格初始化：
Ext.define('akma.chat.view.TopicGrid', {
alias: 'widget.akma.chat.view.TopicGrid',
extend: 'akma.chat.view.grid.DefaultChatMessageGrid',
requires: ['akma.chat.Chat', 'akma.UIUtils', 'Ext.grid.plugin.BufferedRenderer'],
features: [],
hasPagingBar: false,
height: 500,
loadedMsg: 0,
currentPage: 0,
oldId: undefined,
forceFit: true,
itemId: 'topicGrid',
selModel: {
pruneRemoved: false
},
multiSelect: true,
viewConfig: {
trackOver: false
},
plugins: [{
ptype: 'bufferedrenderer',
pluginId: 'bufferedrenderer',
variableRowHeight: true,
trailingBufferZone: 5,
leadingBufferZone: 5,
scrollToLoadBuffer: 10
}],
tbar: [{
text: 'unmask',
handler: function(){
this.up('#topicGrid').getView().loadMask.hide();
}
}],
constructor: function (config) {
this.topicId = config.topicId;
this.store = akma.chat.Chat.getMessageStoreInstance(this.topicId);
this.topic = akma.chat.Chat.getTopic(this.topicId);
var topicPanel = this;
this.store.on('load', function (store, records) {
var loadedMsg = store.getTotalCount();
var pageSize = store.pageSize;
store.currentPage = Math.ceil(loadedMsg/pageSize);
if (records && records.length > 0) {
var newId = records[0].data.id;
if (topicPanel.oldId) {
var element;
for (var i = topicPanel.oldId; i < newId; i++) {
element = Ext.get(i + '');
topicPanel.blinkMessage(element);
}
}
topicPanel.oldId = records[records.length-1].data.id;
var view = topicPanel.getView();
view.refresh();
topicPanel.getPlugin('bufferedrenderer').scrollTo(store.getTotalCount()-1);
}
});
this.callParent(arguments);
this.on('afterrender', function (grid) {
grid.getStore().load();
});
var me = this;
akma.UIUtils.onPasteArray.push(function (e, it) {
if(e.clipboardData){
var items = e.clipboardData.items;
for (var i = 0; i < items.length; ++i) {
if (items[i].kind == 'file' && items[i].type.indexOf('image/') !== -1) {
var blob = items[i].getAsFile();
akma.chat.Chat.upload(blob, function (event) {
var response = Ext.JSON.decode(event.target.responseText);
var fileId = response.rows[0].id;
me.sendMessage('<img src="/chat/services/file?id=' + fileId + '" />');
})
}
}
}
});
akma.UIUtils.addOnPasteListener();
},
sendMessage: function(message){
if(message){
var topicGrid = this;
Ext.Ajax.request({
method: 'POST',
url: topicGrid.store.proxy.url,
params:{
rows: Ext.encode([{"message":message,"topic":{"id":topicGrid.topicId}}])
}
});
}
},
blinkMessage: function (messageElement) {
if (messageElement) {
var blinking = setInterval(function () {
messageElement.removeCls('red');
messageElement.addCls('yellow');
setTimeout(function () {
messageElement.addCls('red');
messageElement.removeCls('yellow');
}, 250)
}, 500);
setTimeout(function () {
clearInterval(blinking);
messageElement.addCls('red');
messageElement.removeCls('yellow');
}, this.showInterval ? this.showInterval : 3000)
}
},
columns: [ {
dataIndex: 'message',
text: 'Message',
renderer: function (value, p, record) {
var firstSpan = "<span id='" + record.data.id + "'>";
var creator = record.data.creator;
return Ext.String.format('<div style="white-space:normal !important;">{3}{1} : {0}{4}</div>',
value,
creator ? '<span style="color: #' + creator.chatColor + ';">' + creator.username + '</span>' : 'N/A',
record.data.id,
firstSpan,
'</span>'
);
}
}
]
});
upd：似乎问题不在视图中。bufferedrenderer 插件绑定滚动到记录。它运行一个回调函数：
callback: function(range, start, end) {
me.renderRange(start, end, true);
targetRec = store.data.getRange(recordIdx, recordIdx)[0];
......
store.data.getRange(recordIdx, recordIdx)[0]
尝试获取商店中的最后一条记录。……
Ext.Array.push(result, Ext.Array.slice(me.getPage(pageNumber), sliceBegin, sliceEnd));
getPage 返回给定页面的所有记录，但缺少最后一条记录，即商店没有完美更新。
任何想法如何解决？