核取方塊與單選按鈕
使用我們完全重新編寫的核取元件,建立跨瀏覽器和跨裝置一致的核取方塊和單選按鈕。
方法(Approach)
瀏覽器預設的核取方塊和單選按鈕透過 .form-check 取代,這是一系列適用於兩種輸入類型的類別,可以改善其 HTML 元素的版面配置和行為,提供更大的自訂彈性和跨瀏覽器的一致性。核取方塊用於在清單中選擇一個或多個選項,而單選按鈕用於從多個選項中選擇一個。
在結構上,我們的 <input> 和 <label> 是同層元素,而不是將 <input> 放在 <label> 內部。這稍微繁瑣一些,因為您必須指定 id 和 for 屬性來關聯 <input> 和 <label>。我們對所有 <input> 狀態使用同層選擇器(~),例如 :checked 或 :disabled。當與 .form-check-label 類別結合使用時,我們可以根據 <input> 的狀態輕鬆設定每個項目的文字樣式。
我們的核取方塊使用自訂的 Bootstrap 圖示來表示已選取或不確定狀態。
核取方塊(Checks)
<div class="form-check">
<input class="form-check-input" type="checkbox" value="" id="checkDefault">
<label class="form-check-label" for="checkDefault">
Default checkbox
</label>
</div>
<div class="form-check">
<input class="form-check-input" type="checkbox" value="" id="checkChecked" checked>
<label class="form-check-label" for="checkChecked">
Checked checkbox
</label>
</div> 不確定狀態(Indeterminate)
核取方塊可以透過 JavaScript 手動設定來使用 :indeterminate 偽類別(沒有可用的 HTML 屬性來指定它)。
<div class="form-check">
<input class="form-check-input" type="checkbox" value="" id="checkIndeterminate">
<label class="form-check-label" for="checkIndeterminate">
Indeterminate checkbox
</label>
</div> 停用(Disabled)
加入 disabled 屬性,相關聯的 <label> 會自動以較淺的顏色設定樣式,以幫助表示輸入欄位的狀態。
<div class="form-check">
<input class="form-check-input" type="checkbox" value="" id="checkIndeterminateDisabled" disabled>
<label class="form-check-label" for="checkIndeterminateDisabled">
Disabled indeterminate checkbox
</label>
</div>
<div class="form-check">
<input class="form-check-input" type="checkbox" value="" id="checkDisabled" disabled>
<label class="form-check-label" for="checkDisabled">
Disabled checkbox
</label>
</div>
<div class="form-check">
<input class="form-check-input" type="checkbox" value="" id="checkCheckedDisabled" checked disabled>
<label class="form-check-label" for="checkCheckedDisabled">
Disabled checked checkbox
</label>
</div> 單選按鈕(Radios)
<div class="form-check">
<input class="form-check-input" type="radio" name="radioDefault" id="radioDefault1">
<label class="form-check-label" for="radioDefault1">
Default radio
</label>
</div>
<div class="form-check">
<input class="form-check-input" type="radio" name="radioDefault" id="radioDefault2" checked>
<label class="form-check-label" for="radioDefault2">
Default checked radio
</label>
</div> 停用(Disabled)
加入 disabled 屬性,相關聯的 <label> 會自動以較淺的顏色設定樣式,以幫助表示輸入欄位的狀態。
<div class="form-check">
<input class="form-check-input" type="radio" name="radioDisabled" id="radioDisabled" disabled>
<label class="form-check-label" for="radioDisabled">
Disabled radio
</label>
</div>
<div class="form-check">
<input class="form-check-input" type="radio" name="radioDisabled" id="radioCheckedDisabled" checked disabled>
<label class="form-check-label" for="radioCheckedDisabled">
Disabled checked radio
</label>
</div> 切換開關(Switches)
切換開關具有自訂核取方塊的標記,但使用 .form-switch 類別來呈現切換開關。考慮使用 role="switch" 以更準確地向支援此角色的輔助技術傳達控制項的性質。在較舊的輔助技術中,它將簡單地作為普通核取方塊來宣告作為備用方案。切換開關也支援 disabled 屬性。
<div class="form-check form-switch">
<input class="form-check-input" type="checkbox" role="switch" id="switchCheckDefault">
<label class="form-check-label" for="switchCheckDefault">Default switch checkbox input</label>
</div>
<div class="form-check form-switch">
<input class="form-check-input" type="checkbox" role="switch" id="switchCheckChecked" checked>
<label class="form-check-label" for="switchCheckChecked">Checked switch checkbox input</label>
</div>
<div class="form-check form-switch">
<input class="form-check-input" type="checkbox" role="switch" id="switchCheckDisabled" disabled>
<label class="form-check-label" for="switchCheckDisabled">Disabled switch checkbox input</label>
</div>
<div class="form-check form-switch">
<input class="form-check-input" type="checkbox" role="switch" id="switchCheckCheckedDisabled" checked disabled>
<label class="form-check-label" for="switchCheckCheckedDisabled">Disabled checked switch checkbox input</label>
</div> 原生切換開關(Native switches)
透過在輸入欄位上加入 switch 屬性,為行動版 Safari(iOS 17.4+)逐步增強您的切換開關,以便在切換時啟用觸覺回饋,就像原生 iOS 切換開關一樣。在 Bootstrap 中使用此屬性不會有任何樣式變化,因為我們所有的切換開關都使用自訂樣式。
<div class="form-check form-switch">
<input class="form-check-input" type="checkbox" value="" id="checkNativeSwitch" switch>
<label class="form-check-label" for="checkNativeSwitch">
Native switch haptics
</label>
</div> 請務必在 WebKit 部落格上閱讀更多關於 switch 屬性的資訊。macOS 和 iOS 上的 Safari 17.4+ 都在 HTML 中提供原生樣式的切換開關,而其他瀏覽器則簡單地回退到標準的核取方塊外觀。在較新版本的 Safari 中,將此屬性套用於非 Bootstrap 核取方塊將呈現原生切換開關。
預設(堆疊)(Default (stacked))
預設情況下,任何數量的核取方塊和單選按鈕如果是直接相鄰的同層元素,將會使用 .form-check 垂直堆疊並適當地間隔。
<div class="form-check">
<input class="form-check-input" type="checkbox" value="" id="defaultCheck1">
<label class="form-check-label" for="defaultCheck1">
Default checkbox
</label>
</div>
<div class="form-check">
<input class="form-check-input" type="checkbox" value="" id="defaultCheck2" disabled>
<label class="form-check-label" for="defaultCheck2">
Disabled checkbox
</label>
</div> <div class="form-check">
<input class="form-check-input" type="radio" name="exampleRadios" id="exampleRadios1" value="option1" checked>
<label class="form-check-label" for="exampleRadios1">
Default radio
</label>
</div>
<div class="form-check">
<input class="form-check-input" type="radio" name="exampleRadios" id="exampleRadios2" value="option2">
<label class="form-check-label" for="exampleRadios2">
Second default radio
</label>
</div>
<div class="form-check">
<input class="form-check-input" type="radio" name="exampleRadios" id="exampleRadios3" value="option3" disabled>
<label class="form-check-label" for="exampleRadios3">
Disabled radio
</label>
</div> 行內(Inline)
透過在任何 .form-check 上加入 .form-check-inline,將核取方塊或單選按鈕分組在同一水平列上。
<div class="form-check form-check-inline">
<input class="form-check-input" type="checkbox" id="inlineCheckbox1" value="option1">
<label class="form-check-label" for="inlineCheckbox1">1</label>
</div>
<div class="form-check form-check-inline">
<input class="form-check-input" type="checkbox" id="inlineCheckbox2" value="option2">
<label class="form-check-label" for="inlineCheckbox2">2</label>
</div>
<div class="form-check form-check-inline">
<input class="form-check-input" type="checkbox" id="inlineCheckbox3" value="option3" disabled>
<label class="form-check-label" for="inlineCheckbox3">3 (disabled)</label>
</div> <div class="form-check form-check-inline">
<input class="form-check-input" type="radio" name="inlineRadioOptions" id="inlineRadio1" value="option1">
<label class="form-check-label" for="inlineRadio1">1</label>
</div>
<div class="form-check form-check-inline">
<input class="form-check-input" type="radio" name="inlineRadioOptions" id="inlineRadio2" value="option2">
<label class="form-check-label" for="inlineRadio2">2</label>
</div>
<div class="form-check form-check-inline">
<input class="form-check-input" type="radio" name="inlineRadioOptions" id="inlineRadio3" value="option3" disabled>
<label class="form-check-label" for="inlineRadio3">3 (disabled)</label>
</div> 反向(Reverse)
使用 .form-check-reverse 修飾類別,將您的核取方塊、單選按鈕和切換開關放在相反的一側。
<div class="form-check form-check-reverse">
<input class="form-check-input" type="checkbox" value="" id="reverseCheck1">
<label class="form-check-label" for="reverseCheck1">
Reverse checkbox
</label>
</div>
<div class="form-check form-check-reverse">
<input class="form-check-input" type="checkbox" value="" id="reverseCheck2" disabled>
<label class="form-check-label" for="reverseCheck2">
Disabled reverse checkbox
</label>
</div>
<div class="form-check form-switch form-check-reverse">
<input class="form-check-input" type="checkbox" id="switchCheckReverse">
<label class="form-check-label" for="switchCheckReverse">Reverse switch checkbox input</label>
</div> 無標籤(Without labels)
對於沒有標籤文字的核取方塊和單選按鈕,省略包裝的 .form-check。請記住仍然為輔助技術提供某種形式的無障礙名稱(例如,使用 aria-label)。有關詳細資訊,請參閱表單概覽無障礙部分。
<div>
<input class="form-check-input" type="checkbox" id="checkboxNoLabel" value="" aria-label="...">
</div>
<div>
<input class="form-check-input" type="radio" name="radioNoLabel" id="radioNoLabel1" value="" aria-label="...">
</div> 切換按鈕(Toggle buttons)
透過在 <label> 元素上使用 .btn 樣式而不是 .form-check-label,建立類似按鈕的核取方塊和單選按鈕。如果需要,這些切換按鈕可以進一步分組在按鈕群組中。
核取方塊切換按鈕(Checkbox toggle buttons)
<input type="checkbox" class="btn-check" id="btn-check" autocomplete="off">
<label class="btn btn-primary" for="btn-check">Single toggle</label>
<input type="checkbox" class="btn-check" id="btn-check-2" checked autocomplete="off">
<label class="btn btn-primary" for="btn-check-2">Checked</label>
<input type="checkbox" class="btn-check" id="btn-check-3" autocomplete="off" disabled>
<label class="btn btn-primary" for="btn-check-3">Disabled</label> <input type="checkbox" class="btn-check" id="btn-check-4" autocomplete="off">
<label class="btn" for="btn-check-4">Single toggle</label>
<input type="checkbox" class="btn-check" id="btn-check-5" checked autocomplete="off">
<label class="btn" for="btn-check-5">Checked</label>
<input type="checkbox" class="btn-check" id="btn-check-6" autocomplete="off" disabled>
<label class="btn" for="btn-check-6">Disabled</label> 在視覺上,這些核取方塊切換按鈕與按鈕外掛切換按鈕相同。然而,輔助技術對它們的傳達方式不同:核取方塊切換會被螢幕閱讀器宣告為「已勾選」/「未勾選」(因為儘管它們的外觀,它們基本上仍然是核取方塊),而按鈕外掛切換按鈕會被宣告為「按鈕」/「按鈕已按下」。這兩種方法之間的選擇將取決於您正在建立的切換類型,以及當宣告為核取方塊或實際按鈕時,切換對使用者是否有意義。
單選按鈕切換按鈕(Radio toggle buttons)
<input type="radio" class="btn-check" name="options" id="option1" autocomplete="off" checked>
<label class="btn btn-secondary" for="option1">Checked</label>
<input type="radio" class="btn-check" name="options" id="option2" autocomplete="off">
<label class="btn btn-secondary" for="option2">Radio</label>
<input type="radio" class="btn-check" name="options" id="option3" autocomplete="off" disabled>
<label class="btn btn-secondary" for="option3">Disabled</label>
<input type="radio" class="btn-check" name="options" id="option4" autocomplete="off">
<label class="btn btn-secondary" for="option4">Radio</label> <input type="radio" class="btn-check" name="options-base" id="option5" autocomplete="off" checked>
<label class="btn" for="option5">Checked</label>
<input type="radio" class="btn-check" name="options-base" id="option6" autocomplete="off">
<label class="btn" for="option6">Radio</label>
<input type="radio" class="btn-check" name="options-base" id="option7" autocomplete="off" disabled>
<label class="btn" for="option7">Disabled</label>
<input type="radio" class="btn-check" name="options-base" id="option8" autocomplete="off">
<label class="btn" for="option8">Radio</label> 外框樣式(Outlined styles)
支援 .btn 的不同變體,例如各種外框樣式。
<input type="checkbox" class="btn-check" id="btn-check-outlined" autocomplete="off">
<label class="btn btn-outline-primary" for="btn-check-outlined">Single toggle</label><br>
<input type="checkbox" class="btn-check" id="btn-check-2-outlined" checked autocomplete="off">
<label class="btn btn-outline-secondary" for="btn-check-2-outlined">Checked</label><br>
<input type="radio" class="btn-check" name="options-outlined" id="success-outlined" autocomplete="off" checked>
<label class="btn btn-outline-success" for="success-outlined">Checked success radio</label>
<input type="radio" class="btn-check" name="options-outlined" id="danger-outlined" autocomplete="off">
<label class="btn btn-outline-danger" for="danger-outlined">Danger radio</label> CSS
Sass 變數(Sass variables)
核取方塊的變數:
$form-check-input-width: 1em;
$form-check-min-height: $font-size-base * $line-height-base;
$form-check-padding-start: $form-check-input-width + .5em;
$form-check-margin-bottom: .125rem;
$form-check-label-color: null;
$form-check-label-cursor: null;
$form-check-transition: null;
$form-check-input-active-filter: brightness(90%);
$form-check-input-bg: $input-bg;
$form-check-input-border: var(--#{$prefix}border-width) solid var(--#{$prefix}border-color);
$form-check-input-border-radius: .25em;
$form-check-radio-border-radius: 50%;
$form-check-input-focus-border: $input-focus-border-color;
$form-check-input-focus-box-shadow: $focus-ring-box-shadow;
$form-check-input-checked-color: $component-active-color;
$form-check-input-checked-bg-color: $component-active-bg;
$form-check-input-checked-border-color: $form-check-input-checked-bg-color;
$form-check-input-checked-bg-image: url("data:image/svg+xml,<svg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 20 20'><path fill='none' stroke='#{$form-check-input-checked-color}' stroke-linecap='round' stroke-linejoin='round' stroke-width='3' d='m6 10 3 3 6-6'/></svg>");
$form-check-radio-checked-bg-image: url("data:image/svg+xml,<svg xmlns='http://www.w3.org/2000/svg' viewBox='-4 -4 8 8'><circle r='2' fill='#{$form-check-input-checked-color}'/></svg>");
$form-check-input-indeterminate-color: $component-active-color;
$form-check-input-indeterminate-bg-color: $component-active-bg;
$form-check-input-indeterminate-border-color: $form-check-input-indeterminate-bg-color;
$form-check-input-indeterminate-bg-image: url("data:image/svg+xml,<svg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 20 20'><path fill='none' stroke='#{$form-check-input-indeterminate-color}' stroke-linecap='round' stroke-linejoin='round' stroke-width='3' d='M6 10h8'/></svg>");
$form-check-input-disabled-opacity: .5;
$form-check-label-disabled-opacity: $form-check-input-disabled-opacity;
$form-check-btn-check-disabled-opacity: $btn-disabled-opacity;
$form-check-inline-margin-end: 1rem;
切換開關的變數:
$form-switch-color: rgba($black, .25);
$form-switch-width: 2em;
$form-switch-padding-start: $form-switch-width + .5em;
$form-switch-bg-image: url("data:image/svg+xml,<svg xmlns='http://www.w3.org/2000/svg' viewBox='-4 -4 8 8'><circle r='3' fill='#{$form-switch-color}'/></svg>");
$form-switch-border-radius: $form-switch-width;
$form-switch-transition: background-position .15s ease-in-out;
$form-switch-focus-color: $input-focus-border-color;
$form-switch-focus-bg-image: url("data:image/svg+xml,<svg xmlns='http://www.w3.org/2000/svg' viewBox='-4 -4 8 8'><circle r='3' fill='#{$form-switch-focus-color}'/></svg>");
$form-switch-checked-color: $component-active-color;
$form-switch-checked-bg-image: url("data:image/svg+xml,<svg xmlns='http://www.w3.org/2000/svg' viewBox='-4 -4 8 8'><circle r='3' fill='#{$form-switch-checked-color}'/></svg>");
$form-switch-checked-bg-position: right center;