[Tree] uncheck tree half-checked node clicking on its checkbox.

[sanova]

In the tree when an half-checked node has been clicked its status becomes checked. There is no way to override this behavior and instead set it unchecked. This could be useful when a node has a lot of children that are set checked as parent and the checks trigger a lot of functions. it could cause problems in the code execution.

Anyway for who has to do something like that, here how i achieve the aim:

<el-tree
	ref="tree"
	node-key="id"
	show-checkbox
	@check-change="toggleItem"
	@check="toggleCheck">
</el-tree>

toggleItem(item, checked) {
	if(item.halfChecked && checked) {
	       this.halfClicked = true;
	}
	if(item.halfChecked && !checked) {
	       item.halfChecked = false;
	}
	// Prevent doing anything if an half has been clicked
	if(checked && !this.halfClicked) {
		... do something for checked node
	}
}

toggleCheck(item, treeStatus) {
	treeStatus.halfCheckedNodes.forEach(node => {
	        node.halfChecked = true;
	});
	
	if(item.halfChecked) {
		// set half unchecked
		this.$refs.tree?.setChecked(item.id, false);
		// Set all children unchecked
		this.setChildrenNodesChecked(item, false);
		item.checked = false;
		this.halfClicked = false;
	}
},

setChildrenNodesChecked(node, checked) {
	let children = getChildrenNodes(node) <-- here you have to implement you own function to get children nodes
	children.forEach(node => {
		this.$refs.tree?.setChecked(node.id, checked);
	})
},