I've got a problem and hope you can help me.
I have multiple QQmlWidgets where different instances of same components should be shown.
The components are created at runtime and use specific properties from it's parent widget.
The problem is, that there are multiple nested items in those components, so they are loading very slow.
I've decided to load them all to QQmlEngine at application preload stage, and after just create them when necessary.
So all my QQmlWidgets got same QQmlEngine and same root context.
To differ properties of different widgets I'm creating every instance of component in separate context (one per QQmlWidget).
After creating I'm setting parent item of newly created object to root item of QQmlWidget;
The problem is that the root item is referenced in the dynamically created objects and they could not find it.
Can you suggest any solution? I'm posting simplified version of my code below.
// main.cpp
QQmlEngine* e = new QQmlEngine;
QWidget* ww1 = new QWidget;
QWidget* ww2 = new QWidget;
QQuickWidget* w1 = new QQuickWidget(e, ww1);
QQuickWidget* w2 = new QQuickWidget(e, ww2);
w1->setSource(QUrl::fromLocalFile("main.qml"));
w2->setSource(QUrl::fromLocalFile("main.qml"));
QQmlComponent* comp = new QQmlComponent(e, "comp.qml");
QQmlContext* c1 = new QQmlContext(e);
QQmlContext* c2 = new QQmlContext(e);
QQuickItem* it1 = qobject_cast<QQuickItem*>(comp->create(c1));
it1->setParentItem(w1->rootObject());
QQuickItem* it2 = qobject_cast<QQuickItem*>(comp->create(c2));
it2->setParentItem(w2->rootObject());
ww1->show();
ww2->show();
//main.qml
Rectangle {
id: root
}
//comp.qml
Rectangle {
anchors.top : root.top
}
the error:
comp.qml - ReferenceError: root is not defined
Thanks in advance.
When a component is being loaded a parent is not set and it becomes set only after call of setParentItem method. It can be fixed by setting anchor when parent changes.
// comp.qml
Rectangle {
onParentChanged: { anchors.top = parent.top; }
}
Related
I use vue.js now for about a month and wanted to use the vue-grid-layout to build up a grid 8x4. Is there a possibility to exchange the widgets by each other or is it only possible to put it in between and push it to the bottom?
Example by dragging c to a:
a b c d
gets
c b d
a
But what I want to achieve is:
a b c d
gets
c b a d
What is the best way to implement such a behavior?
Do I have to use a different grid engine?
if so, which one would you prefer?
Thx in advance
Pedy
In order to achieve this effect, you are going to have to orchestrate several events on several components, and signal from the children to the parent when certian things happen.
We have 2 components involved in this operation - the parent component and the draggable child component (which has multiple instances). In the parents template we have the following...
<div id="dropTargetDiv" #drop.prevent="drop" v-on:startIndex="setStartIndex(value)" v-on:targetIndex="setTargetIndex(value)">
<draggable-component v-for="(itemData, index) in dataArray" :itemData="itemData" index="index"/>
</div>
The parent also has these methods...
setStartIndex(value) {
this.startIndex = value;
},
setTargetIndex(value) {
this.targetIndex = value;
},
drop(event) {
this.swapElements(this.startIndex, this.targetIndex);
},
swapElements(start, target) {
// Clone the original array
var newArray = JSON.parse(JSON.stringify(this.dataArray));
// Swap elements
var startElement = newArray[start];
var targetElement = newArray[target];
newArray[target] = startElement;
newArray[start] = targetElement;
// Update the UI
this.dataArray = newArray;
}
In the child component, on its root element, we have the following...
<div class="draggableItem" draggable="true" #dragstart="$emit('startIndex', this.index)" #dragenter.prevent="$emit('targetIndex', this.index)">
If you see that the target index isn't being set correctly, you may want to replace the #dragenter.prevent with #dragover.prevent.
This should work - comments are welcome. You will need to drop on top of another child, not between them.
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
How can I receive all events attached to an element with dojo?
dojo.query('#mydiv') // which events does #mydiv has?
To get all events on a DOM element:
// Get my div
myDiv = dojo.byId("myDiv");
// Obtain all event-related attributes
var events = dojo.filter(
myDiv.attributes,
function(item) {
return item.name.substr(0, 2) == 'on';
}
);
// Execute first found event, just for fun
eval(events[0].value);
If you get myDiv using dojo.query, remember that dojo.query returns an array, so your element would be in myDiv[0].
This solution does not work with events attached with dojo.connect. There probably is a way to extract this info from Dojo inner workings, but you would have to delve into the source code to understand how.
Another option is that you explicitly manage all dojo.connect events with a global registry. You could use dojox.collections to make this easier. For example, creating a global registry whose keys will be the dom nodes, and values will be the handles returned by dojo.connect (these handles contain the dom node, the type of event and the function to execute):
// On startup
dojo.require(dojox.collections.Dictionary);
eventRegistry = new dojox.collections.Dictionary();
...
// Registering an event for dom node with id=myDiv
var handle1 = dojo.connect(dojo.byId("myDiv"), "onclick", null, "clickHandler");
// Check if event container (e.g. an array) for this dom node is already created
var domNode = handle1[0];
if (!eventRegistry.containsKey(domNode))
eventRegistry.add(domNode, new Array());
eventRegistry.item(domNode).push(handle1);
...
// Add another event later to myDiv, assume container (array) is already created
var handle2 = dojo.connect(dojo.byId("myDiv"), "onmouseover", null, "mouseHandler");
eventRegistry.item(domNode).push(handle2);
...
// Later get all events attached to myDiv, and print event names
allEvents = eventRegistry.item(domNode);
dojo.forEach(
allEvents,
function(item) {
console.log(item[1]);
// Item is the handler returned by dojo.connect, item[1] is the name of the event!
}
);
You can hide the annoying check to see if event container is already created by creating a subclass of dojox.collections.Dictionary with this check already incorporated. Create a js file with this path fakenmc/EventRegistry.js, and put it beside dojo, dojox, etc:
dojo.provide('fakenmc.EventRegistry');
dojo.require('dojox.collections.Dictionary');
dojo.declare('fakenmc.EventRegistry', dojox.collections.Dictionary, {
addEventToNode : function(djConnHandle) {
domNode = djConnHandle[0];
if (!this.containsKey(domNode))
this.add(domNode, new Array());
this.item(domNode).push(djConnHandle);
}
});
Using the above class you would have to dojo.require('fakenmc.EventRegistry') instead of 'dojox.collections.Dictionary', and would simply directly add the dojo connect handle without other checks:
dojo.provide('fakenmc.EventRegistry');
eventRegistry = new fakenmc.EventRegistry();
var handle = dojo.connect(dojo.byId("myDiv"), "onclick", null, "clickHandler");
eventRegistry.addEventToNode(handle);
...
// Get all events attached to node
var allEvents = eventRegistry.item(dojo.byId("myDiv"));
...
This code is not tested, but I think you get the idea.
If its only for debugging purpose. You can try dijit.byId("myId").onClick.toString(); in your firebug console and you can see the entire onclick code this works even if the function is anonymous you can view the content of anonymous content.
I would like to know if there is a way to move the node programmatically in dojo Dnd? The reason is I would like to revert the changes to the drag and drop when the web service call triggered a failed save on the database. Here is what I have so far.
In my code, the node Id seems to be unrecognized by the dojo.dnd.Container.DelItem. I cannot just use the selected item on the target because this is a asynchronous webservice function callback. So the user may be selecting another node on the container when this is called.
function OnMoveWSComplete(strResult) {
var resultObj = eval('(' + strResult + ')');
var sourceContainer = eval('(' + objResult.sourceContainerId + ')');
var targetContainer = eval('(' + objResult.targetContainerId + ')');
var targetNodes = targetContainer.getAllNodes();
for (var iNode = 0; iNode < targetNodes.length; iNode++) {
var currId = getLastIdFromStr(targetNodes[iNode].id);
if (currId == resultObj.Id) {
var targetN = targetNodes[iNode];
var Name = targetNodes[iNode].childNodes[0].nodeValue;
targetContainer.delItem(targetNodes[iNode].id);
var origData = { Id: resultObj.Id, Name: Name };
sourceContainer.insertNodes(true, origData);
break;
}
}
}
EDIT: Solution (Thanks Eugene Lazutkin) [2009/11/30]:
/**
* Move one node from one container to the other
*/
function moveNode(nodeId, sourceContainer, targetContainer) {
var node = dojo.byId(nodeId);
// Save the data
var saveData = sourceContainer.map[nodeId].data;
// Do the move
sourceContainer.parent.removeChild(node);
targetContainer.parent.appendChild(node);
// Sync the DOM object → map
sourceContainer.sync();
targetContainer.sync();
// Restore data for recreation of data
targetContainer.map[nodeId].data = saveData;
}
It looks like you assume that delItem removes physical nodes. Take a look at the documentation — probably you want to move nodes between containers instead of deleting them from the map. One simple way to do that just to move DOM nodes between containers, and call sync() on both containers.
Addition: Here is a super-simple pseudocode-like example:
function move(node, source, target){
// normalize node and/or node id
node = dojo.byId(node);
// move it physically from one parent to another
// (from target to source) adding to the end
target.parent.appenChild(node);
// now it is moved from source to target
// let's synchronize both dojo.dnd.Source's
source.sync();
target.sync();
}
Or something along these lines should work. The important pieces:
Move node from one parent to another using any DOM operations you deem appropriate. I used appendChild(), but you can use insertBefore(), or anything else.
Synchronize both sources involved after the move.
Obviously it works if both sources use nodes of the same type and structure. If not, you should do something more complex, e.g., move everything you need emulating a real DnD move by publishing topics described in the documentation.
I have this function which moves selected nodes by button click:
source.forInItems(dojo.hitch(this, function(item, id, map) {
if (dojo.hasClass(id, "dojoDndItemAnchor")) {
target.onDrop(source, [ dojo.byId(id) ], false);
dojo.removeClass(id, "dojoDndItemAnchor");
}
}));
onDrop() is an overridable method, which is called upon item drop, and by default calls to method onDropExternal(source, nodes, copy).
I am doing the same thing right now. I was able to solve by doing the following.
Set the dnd/Source autoSync property to true
<div data-dojo-type="dojo.dnd.Source" accept="widget" class="source" data-dojo-props="autoSync: true">
After dragging it looses the dndtype so I had to re-add it using client side code. Also I remove the dojoDndItemAnchor class after drop.
$(node).removeClass('dojoDndItemAnchor').attr('dndtype', 'widget');
Using Dojo 1.3, after adding a child (i.e. folder or item) to a tree, is there a way to have it reflected immediately via refresh or some other method?
From the official Dojo manual
Updating a Tree
People often ask:
how do I update a tree (adding or
deleting items?)
You can't update the
tree directly, but rather you need to
update the model. Usually the model is
connected to a data store and in that
case you need to update the data
store. Thus, you need to use a data
store that allows updates (through
it's official API), like
dojo.data.ItemFileWriteStore.
how do I refresh a Tree from the
store?
This isn't supported. The store
needs to notify the tree of any
changes to the data. Currently this is
really only supported (out of the box)
by dojo.data.ItemFileWriteStore, as
setting up a client-server dojo.data
source where the server notifies the
client whenever the data has changed
is quite complicated, and beyond the
scope of dojo, which is a client-only
solution.
Say, if your model has the query `{type:'continent'} - meaning any items with this property are top-level-items, then the following will model extension will monitor changes and refresh the tree's view
var dataStore = new ItemFileWriteStore( { ... });
new Tree({
store: dataStore,
model: new ForestModel({
onNewItem: function(item, parentInfo){
if(this.store.getValue(item, 'type') == 'continent'){
this._requeryTop();
}
this.inherited(arguments);
}
}
});
This should in turn call childrenChanged in the tree and update it every time a new item is added.
See model reference
As an addition, if the item added is not a toplevel item, an immediate update should be doable with this statement. parent is the treenode which has had an item added to its children.
tree._collapseNode(parent);
parent.state = 'UNCHECKED';
tree._expandNode(parent);
A more or less 'standard' refresh of the tree can be achieved by following. Reason for it not being added to base implementation, i think is because it will break the linkage with DnD features on a tree
dojo.declare("My.Tree", [dijit.Tree], {
// Close the store? (So that the store will do a new fetch()).
reloadStoreOnRefresh : true,
update: function() {
this.model.store.clearOnClose = this.reloadStoreOnRefresh;
this.model.store.close();
// Completely delete every node from the dijit.Tree
delete this._itemNodesMap;
this._itemNodesMap = {};
this.rootNode.state = "UNCHECKED";
delete this.model.root.children;
this.model.root.children = null;
// Destroy the widget
this.rootNode.destroyRecursive();
// Recreate the model, (with the model again)
this.model.constructor(this.model)
// Rebuild the tree
this.postMixInProperties();
this._load();
}
}
);
I've solved this WITHOUT needing the refresh.
_refreshNodeMapping: function (newNodeData) {
if(!this._itemNodesMap[newNodeData.identity]) return;
var nodeMapToRefresh = this._itemNodesMap[newNodeData.identity][0].item;
var domNode = this._itemNodesMap[newNodeData.identity][0].domNode;
//For every updated value, reset the old ones
for(var val in newNodeData)
{
nodeMapToRefresh[val] = newNodeData[val];
if(val == 'label')
{
domNode.innerHTML = newNodeData[val];
}
}
}