125 lines
3.5 KiB
Markdown
125 lines
3.5 KiB
Markdown
---
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title: v-show Does Not Work on template or With v-else
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impact: MEDIUM
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impactDescription: Using v-show on template silently fails, element is always rendered
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type: capability
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tags: [vue3, conditional-rendering, v-show, template, limitations]
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---
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# v-show Does Not Work on template or With v-else
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**Impact: MEDIUM** - `v-show` cannot be used on `<template>` elements because templates don't render to the DOM (so there's nothing to apply `display: none` to). Additionally, `v-show` does not support `v-else`. Using these incorrectly results in elements that are always visible or else branches that never work.
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## Task Checklist
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- [ ] Never use v-show on `<template>` elements - use v-if instead
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- [ ] Never use v-else with v-show - use separate v-show with negated condition
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- [ ] Remember v-show only works on actual DOM elements
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- [ ] If you need to toggle multiple elements frequently, wrap in a real element (div, span)
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**Incorrect:**
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```html
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<!-- WRONG: v-show on <template> - silently does nothing -->
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<template>
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<template v-show="isVisible">
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<h1>Title</h1>
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<p>Content</p>
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</template>
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<!-- These elements will ALWAYS be visible -->
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</template>
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```
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```html
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<!-- WRONG: v-else with v-show - v-else is not supported -->
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<template>
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<div v-show="isLoggedIn">Welcome!</div>
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<div v-else>Please log in</div> <!-- This v-else won't work -->
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</template>
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```
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```html
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<!-- WRONG: Mixing v-show and v-else expectations -->
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<template>
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<span v-show="status === 'success'">Success!</span>
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<span v-else-if="status === 'error'">Error</span> <!-- Not supported -->
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</template>
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```
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**Correct:**
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```html
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<!-- CORRECT: Use v-if on <template> for multiple elements -->
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<template>
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<template v-if="isVisible">
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<h1>Title</h1>
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<p>Content</p>
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</template>
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</template>
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```
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```html
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<!-- CORRECT: Use negated v-show for "else" behavior -->
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<template>
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<div v-show="isLoggedIn">Welcome!</div>
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<div v-show="!isLoggedIn">Please log in</div>
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</template>
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```
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```html
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<!-- CORRECT: Wrap in a real element if you need v-show for multiple elements -->
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<template>
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<div v-show="isVisible">
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<h1>Title</h1>
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<p>Content</p>
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</div>
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</template>
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```
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```html
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<!-- CORRECT: Use v-if/v-else when you need else branches -->
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<template>
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<div v-if="status === 'success'">Success!</div>
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<div v-else-if="status === 'error'">Error</div>
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<div v-else>Loading...</div>
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</template>
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```
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```html
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<!-- CORRECT: Multiple v-show conditions -->
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<template>
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<span v-show="status === 'success'">Success!</span>
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<span v-show="status === 'error'">Error</span>
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<span v-show="status === 'loading'">Loading...</span>
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</template>
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```
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## Why This Limitation Exists
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```javascript
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// v-show works by toggling the CSS display property
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// This requires an actual DOM element
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// <template> is a virtual element - it doesn't render to DOM
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// It's just a wrapper for Vue's rendering logic
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// After compilation:
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// <template v-if="show"><p>Hi</p></template>
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// Renders as: <p>Hi</p> (when show is true)
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// Template itself is gone
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// v-show needs a real element to set display: none on
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// Since <template> doesn't exist in DOM, v-show has nothing to work with
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```
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## When to Choose Each
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| Need | Use |
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|------|-----|
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| Toggle multiple elements with CSS | Wrap in real element + `v-show` |
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| Toggle multiple elements without wrapper | `<template v-if>` |
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| Need v-else branches | `v-if`/`v-else` |
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| Frequent toggle, single element | `v-show` |
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| Frequent toggle, need "else" | Two `v-show` with negated conditions |
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## Reference
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- [Vue.js Conditional Rendering - v-show](https://vuejs.org/guide/essentials/conditional.html#v-show)
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