fix(components): [cascader] add focus and blur event when set filterable

[btea]

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fix #11220

[github-actions]

[github-actions]

🧪 Playground Preview: https://element-plus.run/?pr=11273
Please comment the example via this playground if needed.

[ryuhangyeong]

@btea Hello~ Can you elaborate more on the issue? I'm not sure what the problem is.

[btea]

If filterable and multiple are set at the same time, focus and blur events cannot be triggered.
before

after

[ryuhangyeong]

OK! Thank you for your kind explanation!

[tolking]

It can also optimize the focus. At present, when you press the Tab key, ElInput is triggered for the first time and input is triggered for the second time. You should use tabindex to avoid the first trigger.

[btea]

It can also optimize the focus. At present, when you press the Tab key, ElInput is triggered for the first time and input is triggered for the second time. You should use tabindex to avoid the first trigger.

Good catch 👍

[tolking]

It seems necessary to add focus class to ElInput

[btea]

Do you mean to add is-focus here?

element-plus/packages/components/cascader/src/cascader.vue

Line 124 in aba0d26

:class="nsCascader.e('search-input')"

[tolking]

for ElInput

Currently, there is no style when using the Tab key to focus.

[tolking]

The judgment condition here is insufficient. It cannot accurately determine whether the component is in the focus state

Link

[btea]

I see, indeed as you said, the is-focus judgment ignores el-cascader__search-input.

[tolking]

LGTM.