This is explained on the elementUI official website: setting the indeterminate state is only responsible for style control.
It is used with v-model="checkAll" to change the style of the box in front of "select all"
indeterminate represents an uncertain state of the multi-select box.
true represents: neither all selected nor all unselected. It represents an uncertain state.
false represents: either all selected or all unselected. represents a certain state
So, how do indeterminate and checkAll determine the style of the box in front of "select all"?
for example:
| indeterminate | checkAll | style |
|---|---|---|
| true | true | - |
| true | false | - |
| false | true | √ |
| false | false | none |
[The first two are shown in the figure]
[The third type is shown in the picture]
[The fourth type is shown in the picture]
