// Thanks to https://github.com/andreypopp/react-textarea-autosize/ /** * calculateNodeHeight(uiTextNode, useCache = false) */ const HIDDEN_TEXTAREA_STYLE = ` min-height:0 !important; max-height:none !important; height:0 !important; visibility:hidden !important; overflow:hidden !important; position:absolute !important; z-index:-1000 !important; top:0 !important; right:0 !important ` const SIZING_STYLE = [ 'letter-spacing', 'line-height', 'padding-top', 'padding-bottom', 'font-family', 'font-weight', 'font-size', 'text-rendering', 'text-transform', 'width', 'text-indent', 'padding-left', 'padding-right', 'border-width', 'box-sizing', ] const computedStyleCache = {} let hiddenTextarea function calculateNodeStyling (node, useCache = false) { const nodeRef = ( node.getAttribute('id') || node.getAttribute('data-reactid') || node.getAttribute('name') ) if (useCache && computedStyleCache[nodeRef]) { return computedStyleCache[nodeRef] } const style = window.getComputedStyle(node) const boxSizing = ( style.getPropertyValue('box-sizing') || style.getPropertyValue('-moz-box-sizing') || style.getPropertyValue('-webkit-box-sizing') ) const paddingSize = ( parseFloat(style.getPropertyValue('padding-bottom')) + parseFloat(style.getPropertyValue('padding-top')) ) const borderSize = ( parseFloat(style.getPropertyValue('border-bottom-width')) + parseFloat(style.getPropertyValue('border-top-width')) ) const sizingStyle = SIZING_STYLE .map(name => `${name}:${style.getPropertyValue(name)}`) .join(';') const nodeInfo = { sizingStyle, paddingSize, borderSize, boxSizing, } if (useCache && nodeRef) { computedStyleCache[nodeRef] = nodeInfo } return nodeInfo } export default function calculateNodeHeight ( uiTextNode, useCache = false, minRows = null, maxRows = null, ) { if (!hiddenTextarea) { hiddenTextarea = document.createElement('textarea') document.body.appendChild(hiddenTextarea) } // Fix wrap="off" issue // https://github.com/ant-design/ant-design/issues/6577 if (uiTextNode.getAttribute('wrap')) { hiddenTextarea.setAttribute('wrap', uiTextNode.getAttribute('wrap')) } else { hiddenTextarea.removeAttribute('wrap') } // Copy all CSS properties that have an impact on the height of the content in // the textbox const { paddingSize, borderSize, boxSizing, sizingStyle, } = calculateNodeStyling(uiTextNode, useCache) // Need to have the overflow attribute to hide the scrollbar otherwise // text-lines will not calculated properly as the shadow will technically be // narrower for content hiddenTextarea.setAttribute('style', `${sizingStyle};${HIDDEN_TEXTAREA_STYLE}`) hiddenTextarea.value = uiTextNode.value || uiTextNode.placeholder || '' let minHeight = -Infinity let maxHeight = Infinity let height = hiddenTextarea.scrollHeight let overflowY if (boxSizing === 'border-box') { // border-box: add border, since height = content + padding + border height = height + borderSize } else if (boxSizing === 'content-box') { // remove padding, since height = content height = height - paddingSize } if (minRows !== null || maxRows !== null) { // measure height of a textarea with a single row hiddenTextarea.value = '' const singleRowHeight = hiddenTextarea.scrollHeight - paddingSize if (minRows !== null) { minHeight = singleRowHeight * minRows if (boxSizing === 'border-box') { minHeight = minHeight + paddingSize + borderSize } height = Math.max(minHeight, height) } if (maxRows !== null) { maxHeight = singleRowHeight * maxRows if (boxSizing === 'border-box') { maxHeight = maxHeight + paddingSize + borderSize } overflowY = height > maxHeight ? '' : 'hidden' height = Math.min(maxHeight, height) } } // Remove scroll bar flash when autosize without maxRows if (!maxRows) { overflowY = 'hidden' } return { height, minHeight, maxHeight, overflowY } }