PrimeFaces TreeTable-停止复选框选择传播

Question

环境：
PrimeFaces 6.1
JSF 2.2
Tomcat 7.0.23
Java1.7。0_79

实现了一个带有复选框选择的TreeTable，并且需要分别防止父节点和子节点的选择向上和向下传播以进行客户端和服务器端处理。

示例树：
父节点
--子节点1
--子子节点1.1
--子节点2
----子子节点2.1

所需行为：选择节点时，只应选中该节点的复选框。

实际行为（开箱即用）：
选择节点，子节点和父节点被选中。例如，在上面的示例树中选择子节点2父节点和子子节点2.1也被选中。

TreeTable组件：

<p:treeTable id="treeTable" value="#{Bean.rootNode}" var="item" selectionMode="checkbox" nodeVar="node"
    styleClass="widthFull" showUnselectableCheckbox="true" selection="#{Bean.selectedNodes}" stickyHeader="true">
    <p:ajax event="select" listener="#{Bean.processSelect(item)}" ignoreAutoUpdate="true"/>
    <p:ajax event="unselect" listener="#{Bean.processUnselect(item)}" ignoreAutoUpdate="true"/>
    ....
</p:treeTable>

覆盖PrimeFaces JS函数：
能够通过覆盖PrimeFaces.widget.TreeTable.prototype.propagate和PrimeFaces.widget.TreeTable.prototype.get后代javascript函数来防止客户端处理中的传播。

PrimeFaces.widget.TreeTable.prototype.propagateUp = function(node) {
    //do nothing, overriding the TreeTable propagate selection up functionality

}

PrimeFaces.widget.TreeTable.prototype.getDescendants = function(node) {
    //do nothing other than return empty array, overriding the TreeTable propagate selection down functionality by overriding getDescendants...hopefully this doesn't cause other issues
    f = [];
    return f;
}

树表更新：
树表更新是作为ajax选择和取消选择事件处理的一部分执行的。

RequestContext.getCurrentInstance().update("inventoryForm:treeTable");

问题：当ajax select和unselect事件被触发以禁用特定节点上的可选择性并更新树表时，子节点被选中。处理ajax事件侦听器时，子节点不在Bean上的selectedNodes数组中。如何防止在树表组件更新时选择子节点？

Answer 1

防止复选框选择从服务器端传播可以通过扩展CheckboxTreeNode类并覆盖传播SelectionDown（boolean）和传播SelectionUp（）方法来实现。当然，然后您需要使用新类而不是CheckboxTreeNode构建树内容。

public class MyCheckboxTreeNode extends CheckboxTreeNode {

    public MyCheckboxTreeNode() {
        super();
    }

    public MyCheckboxTreeNode(Object data, TreeNode parent) {
        super(data, parent);
    }

    public MyCheckboxTreeNode(Object data) {
        super(data);
    }

    public MyCheckboxTreeNode(String type, Object data, TreeNode parent) {
        super(type, data, parent);
    }

    @Override
    protected void propagateSelectionDown(boolean value) {
        //Do nothing, overriding CheckboxTreeNode method to prevent propagation down of tree node selections when ajax update is performed.
    }

    @Override
    protected void propagateSelectionUp() {
        //Do nothing, overriding CheckboxTreeNode method to prevent propagation up of tree node selections when ajax update is performed.
    }
}

需要重写额外的PrimeFaces javascript函数，以防止在子节点折叠时向下传播。

//--------Override Primefaces JS
PrimeFaces.widget.TreeTable.prototype.fireSelectNodeEvent = function(b) {
    //Overriding this function in order to prevent selection of descendant nodes when parent is selected. See a.oncomplete function below.
    if (this.isCheckboxSelection()) {
           var e = this
             , a = {
               source: this.id,
               process: this.id
           };
           a.params = [{
               name: this.id + "_instantSelection",
               value: b
           }];
           a.oncomplete = function(k, f, g) {
            //commented out the logic to prevent selection of descendant nodes when parent node is selected
            //if (g.descendantRowKeys && g.descendantRowKeys !== "") {
                   //var j = g.descendantRowKeys.split(",");
                   //for (var h = 0; h < j.length; h++) {
                       //e.addToSelection(j[h])
                   //}
                   //e.writeSelections()
               //}
           }
           ;
           if (this.hasBehavior("select")) {
               var d = this.cfg.behaviors.select;
               d.call(this, a)
           } else {
               PrimeFaces.ajax.AjaxRequest(a)
           }
       } else {
           if (this.hasBehavior("select")) {
               var d = this.cfg.behaviors.select
                 , c = {
                   params: [{
                       name: this.id + "_instantSelection",
                       value: b
                   }]
               };
               d.call(this, c)
           }
       }
}