I am functional component I am using hooks to update the state of the array locationData
const c = {
title: inputValue,
}
setLocationData([...locationData, c]);
This is working fine, but now I want to add the value at the beginning of the array, and not at the end.
Edit:
I also have a problem to delete an item from the array. I want to delete one item, but more are deleted
const deleteItem = (index) => {
console.log(index)
var temp = locationData;
var temp = locationData.splice(index, 1);
setLocationData(temp);
}
You are almost there, just switch the position in the array.
setLocationData([c, ...locationData]);
You should also be aware of other methods like splice, slice, push, pop etc...
Update: Using Splice
This relates to part 2 of your question with regards to removing from specific index.
The splice() method changes the contents of an array by removing or
replacing existing elements and/or adding new elements in place. To
access part of an array without modifying it, see slice().
So your codes should be similar to the following
var temp = [...locationData];
temp.splice(index, 1);
setLocationData(temp);
Related
I am using Vue.Draggable in my Vue project and trying to drag(clone) a button from sider into a draggable component.
I want to modify the data when I clone the button into the component. But I find that when I modify the data in the list which is binded with the component, the original list that sider used got changed automatically.
Is there some kind of synchronization mechanism in Vue.Draggable or something? I want to change the object data in the component only.
I tried to modify the object in the list2 manually by using a vue extension in Chrome browser. And it still happens. So I think maybe it's not bug in my code.
addEntity (conditionID, entity) {
if (!entity.forChoose) {
}
else {
let variable = 0;
for (let i = 0, len = this.whens.length; i < len; i++) {
if (this.whens[i].entity[0].id == entity.id) {
variable++;
}
}
this.whens[conditionID].entity[0].forChoose = false;
this.whens[conditionID].entity[0].variable = variable;
this.whens[conditionID].entity[0].name = entity.name + '-fake';
}
},
The code above is the event when I drag the data into the component, and changed some variable.
Although I did nothing to the original data in the Sider where I cloned the data from, it still got changed as well.
Is there a way to change the dragged data but do not affect the original data?
Please help me, thank you!
I think this is happening because of the immutability.
so can you try using spread operator to create new shallow copy of your list before you change it.
how to use spread operator (triple dot)
let newArrayOfWhens = [...this.whens]
then use the "newArrayOfWhens" array in your code
You can create a deep clone as well if you want, but try to avoid it if it is not necessary.
you can use a library call "lodash" to do it very easily
deepClone
I'm using Vuex with a getter that filters a lot of data and then some components present it to the user grouped by status. The user can increment the visible count of elements per status by 5. How many items are visible currently is on the Vuex store and a getter uses this to create a "View object".
When I update this visibility object the getter is no rerun so something in the dependency tracking went south. I'm not adding or deleteing properties, still I'm using Vue.set(...) just to be sure.
This is the mutation that increments the visible amount of items for a status:
viewMore(state, status) {
console.log('viewMore')
const current = state.visibility.statuses[status]
Vue.set(state.visibility.statuses, status, current + 5)
}
This mutation is running well and I can see in the developer tools how the visibility increments reactively with every commit. Now here is the getter that depends on this data:
visibleProspects(state, getters) {
console.log('visibleProspects')
let result = {}
for (const status in getters.sourceData) {
if (!result[status]) {
result[status] = { prospects: [] }
}
getters.sourceData[status].forEach(function(prospect) {
if (result[status].prospects.length < state.visibility.statuses[status])
result[status].prospects.push(prospect)
})
}
return result
}
What this does is traverses a complex getter named sourceData (not shown here for brevity) and then depending on how many visible items there are it returns a new structure with that maximum in an array. visibleProspects is then used by my components and everything runs fine the first time or if a update the data that sourceData computes (e.g adding / editing / deleting a prospect).. but no matter what I do modifying state.visibility.statuses is not forcing visibleProspects to recompute.
How can I debug this?
You can make deep copy to make it reactive (using JSON.parse(JSON.stringify())
viewMore(state, status) {
console.log('viewMore')
const current = state.visibility.statuses[status]
state.visibility.statuses[status] = current + 5
state.visibility = JSON.parse(JSON.stringify(state.visibility))
}
#ittus 's answer should work. But the clone operation would be heavy if your state is big.
alternatively, you may try using Vue.set on the root state state.visibility instead. This should make the reactivity works as expected.
Vue.set(state.visibility, 'statuses', {
...state.visibility.statuses,
[status]: current + 5
})
I am working to create a grid like component in VueJs. You can see the JSFiddle here: https://jsfiddle.net/masade/nrb9f4j2/
In the above fiddle the <datacell> component is used to allow inline edit for any cell.
I am 'watch'-ing changes to the rows and saving them in local storage
A newly created row is being pushed to parent object by this.$parent.unshift(newrow) in the <addrow> component
The problem is when I add a new row, though it is being added to the rows local storage it is not being watched for changes
Steps to replicate the issue (on JS fiddle):
Click on Add Row and enter a name to add
Once the row is added, click on the second column (year) and update it
Any changes to newly added row is not being updated
However if you refresh the page, and modify the same again, I am able to update it again.
Please help me understand if I am doing something wrong
You stumbled into one of the change detection caveats in Vue. Vue cannot detect when you have added a property to an object using the index of that object.
You define newrow like this:
data: function(){
return {
newrow : {}
}
},
which means that newrow has no properties. After that, you always add properties to newrow using an index, like here:
this.$parent.cols.map(function(col,index){
if(typeof newrow[col.m] == "undefined")
newrow[col.m] = "";
})
This means that Vue doesn't know about any of the properties you just added.
I added a method to your fiddle called makeNewRow which adds the properties you need to newrow correctly using the $set method.
makeNewRow(){
this.newrow = {};
this.$parent.cols.map((col,index) => this.$set(this.newrow, col.m, null))
},
Then I call it in mounted and in your addRow method. This fixes your bug. Here is the updated fiddle.
Note: there was an additional bug in your code that I fixed. If someone opened your app and did not previously have grid-vue-local in their local storage, then the uid for gridStorage would be zero, and the first row they added would have the id 0. To fix this I simply added
save: function (rows) {
gridStorage.uid = rows.length
localStorage.setItem(STORAGE_KEY, JSON.stringify(rows))
}
data(){
return{
items:localStorage.fetch()
}
}
watch:{
items:{
handler:function(items){
localStorage.save(items);
},
deep:true
}
}
you can save in items,and watch items,if the items has changed,it will updata
I had a List that used to work when it was bound directly to a store but now I want that list to get it's data from a queryBy on the original store.
Looking at the documentation is seems like setItems should do what I want.
var myStore = Ext.getStore('myStoreData');
var myData = myStore.queryBy(function(item) {
return item.get('status') !== null;
});
// At this point myData looks valid and has the data I want.
// Ext.apply.create.Class {all: Array[5], items: Array[5], keys: Array[5], indices: Object, map: Object…}
Ext.getCmp('myListComponent').setItems(myData.items);
I keep getting the error "Object [object Object] has no method 'getItemId'". I tried various other incantations but without success. I also took a look at setData and add but without success.
========================
After getting Thiem's answer I just ended up creating a function that would create a filtered copy of an existing store and then just setting the List store to that. Code below for others edification...
storeCopy: function(store, filterBy) {
var records = [];
var allRecords = null;
if(filterBy)
allRecords= store.queryBy(filterBy);
else
allRecords= store.queryBy(function(){return true;});
allRecords.each(function(r){
var rec = r.copy();
rec.setId(r.getId());
records.push(rec);
});
var store2 = new Ext.data.Store({
recordType: store.recordType
});
store2.add(records);
return store2;
},
Thanks all.
setItems method does a totally different thing. For example, says you have an Ext.Container which consists of a form, some fields, and some interaction buttons. These things are call child components, or items of the container. They are oftenly declared in the items config of the parent container and setItems is designed to programmatically set the value of that config. So it has nothing to do with the store logic.
In your situation, here is one of the solutions:
Create a store instance which contains filtered data.
Use this command: yourList.setStore('yourFilteredStore')
And it should reload... hope this helps
I am using extjs 4.1.1a for developing some application.
I had a form consisting of two combo-boxes and an item-selector.
Based on the value selected in first combo-box , the itemselector will load its data from database. This is working fine.
My problem is, if i reselect the first combo-box the new data will be displayed in itemselector along with previous data displayed in itemseletor .That is previous data displayed in itemselector will remain there itself.
for example: name "test1" consists of ids 801,2088,5000. on selecting test1 in firstcombobox itemselector must show output as below.
and if "test2" consists of ids 6090,5040. on selecting test2 in firstcombobox itemselector must show output as below.
problem is. for first time if i select "test1" from firstcombobox , output will come as expected. if i reselect "test2" from firstcombobox , output will come as below.
as you can see, previous data displayed (marked in red rectagle) remains there itself with new data displayed (marked with green rectangle).
I want for every reselection of first combobox, previously displayed data in itemselector to be erased before printing new data on itemselector.
How can I reset the itemselector for every reselection of first combobox?
You should remove all items from the store of the itemselector by the removeAll command. After that you should load the store of the itemselector.
itemselector.store.removeAll();
itemselector.store.load();
Any solutions above solve my problem.
i found solution from Sencha Forum.
https://www.sencha.com/forum/showthread.php?142276-closed-Ext-JS-4.0.2a-itemselector-not-reloading-the-store
in the itemselector.js file, change the line marked below.
populateFromStore: function(store) {
var fromStore = this.fromField.store;
// Flag set when the fromStore has been loaded
this.fromStorePopulated = true;
// THIS LINE BELOW MUST BE CHANGED!!!!!!!!!!!!
fromStore.loadData(store.getRange()); //fromStore.add(store.getRange());
// setValue waits for the from Store to be loaded
fromStore.fireEvent('load', fromStore);
},
You need to insert...
this.reset();
at the head of the function that is inserting the data.
As an example...
Ext.override( Ext.ux.ItemSelector, {
setValue: function(val) {
this.reset();
if (!val) return;
val = val instanceof Array ? val : val.split(this.delimiter);
var rec, i, id;
for (i = 0; i < val.length; i++) {
var vf = this.fromMultiselect.valueField;
id = val[i];
idx = this.toMultiselect.view.store.findBy(function(record){
return record.data[vf] == id;
});
if (idx != -1) continue;
idx = this.fromMultiselect.view.store.findBy(function(record){
return record.data[vf] == id;
});
rec = this.fromMultiselect.view.store.getAt(idx);
if (rec) {
this.toMultiselect.view.store.add(rec);
this.fromMultiselect.view.store.remove(rec);
}
}
}
});
are u got it?
when u select that combobox frist stoe of item selector is null after store load with ur pass the para meters
for example
store.load(null),
store.proxey.url='jso.php?id='+combobox.getrawvalue(),
store.load();
like that so when ur select a value in ur combobox that time ur used a listeners to ur combobox in that listners ur used above code , select ur some value in combobox that time frist store is get null after ur pass some values to json.php then store load with responce so that time old data is remove and new data load in that store
if u post ur code i will give correct code
I ran into the same issue with ExtJS 4.2.1. I got it to work by calling reload() on the data store and then setValue() with an empty string on the item selector in the data store's reload() callback.
Ext.create("Ext.form.field.ComboBox", {
// Other properties removed for brevity
listeners: {
change: function(field, newValue, oldValue, eOpts) {
Ext.getStore("ExampleStore").reload({
callback: function() {
Ext.getCmp("ExampleItemSelector").setValue("");
}
});
}
}
});
Ext.create("Ext.data.Store", {
storeId: "ExampleStore",
// Other properties removed for brevity
});
Ext.create("Ext.form.FormPanel", {
// Other properties removed for brevity
items:[{
xtype: "itemselector",
id: "ExampleItemSelector",
// Other properties removed for brevity
}]
});
For any folks that are curious, I'm fairly convinced there's a bug in the item selector's populateFromStore() function. When the function is called, it blindly adds all of the values from the bound store (store) to the internal store (fromStore). I suspect there should be a call to fromStore.removeAll() prior to the call to fromStore.add(). Here's the relevant code from ItemSelector.js.
populateFromStore: function(store) {
var fromStore = this.fromField.store;
// Flag set when the fromStore has been loaded
this.fromStorePopulated = true;
fromStore.add(store.getRange());
// setValue waits for the from Store to be loaded
fromStore.fireEvent('load', fromStore);
},
EDIT 12/18/2013
If you've configured any callback events on the item selector (e.g. change), you may want to disable the events temporarily when you call setValue(""). For example:
var selector = Ext.getCmp("ExampleItemSelector");
selector.suspendEvents();
selector.setValue("");
selector.resumeEvents();
I had the same problem and finally I decided to modify the extjs source code, not considering it a big issue as extjs itself its saying in the start of the file
Note that this control will most likely remain as an example, and not as a core Ext form
control. However, the API will be changing in a future release and so should not yet be
treated as a final, stable API at this time.
Based on that, as jstricker guessed (and sadly I didn't read and took me a while to arrive to the same conclusion), adding fromStore.removeAll() before fromStore.add() solves the problem.
Outside of the problem (but I think it can be interesting as well), additionally, I also added listConfig: me.listConfig in the MultiSelect configuration (inside createList), that way it's possible to format each item additional options (such as images, etc.) setting in the 'itemselector' the option listConfig as it's explained in the (irrealistic) documentation.
Need to reset the store used in ItemSelector that can be done by setting Empty object like below. Also need to call clearValue() method of ItemSelector component.
store.setData({});
ItemSelectorComponent.clearValue();