下面是Ext.grid.Panel列的渲染器。假设contactStore中有2,000个值,我关心的是基于id(本例中为value参数)的记录名称,而我的网格中只有25行/记录用于我所在的页面。如何动态获取商店以便我获取网格列id的相关关联记录(基于外键),而不是加载所有2,000条记录?有没有办法加载商店然后在回调中,不知何故有这个“渲染器”功能显示回调成功后的值?
columns: [{
...
}, {
header: 'Contact Name',
flex: 1,
sortable: true,
dataIndex: 'contact_id',
renderer: function(value) {
var contactStore = Ext.StoreManager.lookup('Contacts');
return contactStore.getById(value).get('full_name');
}
}, {
答案 0 :(得分:1)
您可以调整collectData(records, startIndex)
中的viewConfig
:
Ext.create('Ext.grid.Panel', {
(...)
viewConfig: {
//this method needs to be adjusted
collectData: function(records, startIndex) {
var me = this;
//we can use a custom function for this
if (me.onBeforeCollectData) {
me.onBeforeCollectData(records);
}
var data = me.superclass.collectData.call(me, records, startIndex);
return data;
},
onBeforeCollectData: function(records) {
var newExtraParams = [];
var oldExtraParams;
var needToLoadStore = false;
var contactStore = Ext.StoreManager.lookup('Contacts');
if (contactStore) {
oldExtraParams = contactStore.oldExtraParams;
} else {
//don't use autLoad: true, this will be a local store
contactStore = Ext.create('Ext.data.Store', {
storeId:'Contacts',
(...)
});
needToLoadStore = true;
}
for (var x in records) {
//contact_id is read out here
var param = records[x].get('contact_id');
if (param) {
if (needToLoadStore == false && Ext.Array.contains(oldExtraParams, param) == false) {
needToLoadStore = true;
}
newExtraParams.push(param);
}
}
if (needToLoadStore == true) {
//we use this to load the store data => because of async: false property
Ext.Ajax.request({
scope: this,
//this is for synchronous calls
async: false,
url: (...),
method: (...),
params: newExtraParams,
success: function (res, opt) {
var responseObj = Ext.decode(res.responseText, false);
contactStore.loadData(responseObj); //or deeper in the responseObj if needed
contactStore.oldExtraParams = newExtraParams;
}
});
}
}
}
});