Angular 8：将 Mat-form-field 中的高度更改为特定像素数

Posted 2023-03-06

【中文标题】Angular 8：将 Mat-form-field 中的高度更改为特定像素数

【英文标题】：Angular 8: Change Height in Mat-form-field to Specific pixel number

【发布时间】：2020-05-15 12:58:31

【问题描述】：

如何将mat-form-field 和appearance="outline" 中的高度更改为特定的高度像素数，40 像素（或未来用户体验团队所需的任何数字）。我需要减少 mat-form-field。

如何做到这一点？公式是什么，或者哪个零件号可以修改为 40px？ -1.1？ .75 , 133%, 使用下面的答案寻找某种函数或数学方程式，或任何其他可能有效的选项。

https://***.com/a/54762506/12425844

::ng-deep .mat-form-field-flex > .mat-form-field-infix  padding: 0.4em 0px !important;
::ng-deep .mat-form-field-label-wrapper  top: -1.5em; 

::ng-deep .mat-form-field-appearance-outline.mat-form-field-can-float.mat-form-field-should-float .mat-form-field-label 
    transform: translateY(-1.1em) scale(.75);
    width: 133.33333%;

【问题讨论】：

height:40px 有什么问题； ? stackblitz.com/edit/angular-31dawx

***.com/questions/54760371/… 不适合你吗？

未指定，已在问题中引用

您是否要设置为精确的 40 像素？你能解释一下演示中有什么问题吗？

你的意思是元素的总大小为 40px，包括填充和提示/错误的空间，还是你的意思是轮廓应该是 40px？

【参考方案1】：

兄弟，我知道你了，一些简单的解决方案是：

将此添加到您的 CSS 中

::ng-deep .mat-form-field-appearance-outline .mat-form-field-flex 
height: 40px !important


::ng-deep .mat-form-field-infix 
padding-top: 1px !important;

解释

您可以在此处随意控制 mat-form-field 的高度。

 ::ng-deep .mat-form-field-appearance-outline .mat-form-field-flex 
    height: 40px !important
    

通过这个波纹管，您可以控制您的 mat-form-field 占位符填充以匹配您放置的新高度。

  ::ng-deep .mat-form-field-infix 
    padding-top: 1px !important;
    

我在这里尝试过并且工作正常

【参考方案2】：

不确定你想从哪里剪裁，所以我给你几个选择，你可以决定剪什么和剪多少，以获得合适的尺寸

从顶部和底部删除边距

::ng-deep mat-form-field.mat-form-field-appearance-outline .mat-form-field-wrapper 
    margin: 0;

改变字体大小

mat-form-field 
    font-size: 10px;

删除提示和错误（底部有空格）

::ng-deep .mat-form-field-wrapper 
    padding-bottom: 0;

::ng-deep .mat-form-field-subscript-wrapper 
    display: none;

更改内边距（顶部和底部默认为 1em）

::ng-deep .mat-form-field-appearance-outline .mat-form-field-infix 
    padding: .5em;

注意：如果您选择做最后一个，您还必须像这样更改.mat-form-field-label 的top 或margin-top

::ng-deep .mat-form-field-appearance-outline .mat-form-field-label 
    top: ...;
    margin-top: ...;

【参考方案3】：

您可以在此处查看您的项目依赖项 (@angular/material 8.2.3)：node_modules\@angular\material\_theming.scss

第 ~ 4540 行：@mixin _mat-form-field-outline-label-floating 和 ma​​t-form-field-outline-typography：

// Used to make instances of the _mat-form-field-label-floating mixin negligibly different,
// and prevent Google's CSS Optimizer from collapsing the declarations. This is needed because some
// of the selectors contain pseudo-classes not recognized in all browsers. If a browser encounters
// an unknown pseudo-class it will discard the entire rule set.
$mat-form-field-outline-dedupe: 0;

// Applies a floating label above the form field control itself.
@mixin _mat-form-field-outline-label-floating($font-scale, $infix-padding, $infix-margin-top) 
  transform: translateY(-$infix-margin-top - $infix-padding + $mat-form-field-outline-dedupe)
  scale($font-scale);
  width: 100% / $font-scale + $mat-form-field-outline-dedupe;

  $mat-form-field-outline-dedupe: $mat-form-field-outline-dedupe + 0.00001 !global;


@mixin mat-form-field-outline-typography($config) 
  // The unit-less line-height from the font config.
  $line-height: mat-line-height($config, input);
  // The amount to scale the font for the floating label and subscript.
  $subscript-font-scale: 0.75;
  // The padding above and below the infix.
  $infix-padding: 1em;
  // The margin applied to the form-field-infix to reserve space for the floating label.
  $infix-margin-top: 1em * $line-height * $subscript-font-scale;
  // The space between the bottom of the .mat-form-field-flex area and the subscript wrapper.
  // Mocks show half of the text size, but this margin is applied to an element with the subscript
  // text font size, so we need to divide by the scale factor to make it half of the original text
  // size.
  $subscript-margin-top: 0.5em / $subscript-font-scale;
  // The padding applied to the form-field-wrapper to reserve space for the subscript, since it's
  // absolutely positioned. This is a combination of the subscript's margin and line-height, but we
  // need to multiply by the subscript font scale factor since the wrapper has a larger font size.
  $wrapper-padding-bottom: ($subscript-margin-top + $line-height) * $subscript-font-scale;
  // The amount we offset the label from the input text in the outline appearance.
  $outline-appearance-label-offset: -0.25em;

  .mat-form-field-appearance-outline 
    .mat-form-field-infix 
      padding: $infix-padding 0 $infix-padding 0;
    

    .mat-form-field-label 
      top: $infix-margin-top + $infix-padding;
      margin-top: $outline-appearance-label-offset;
    

    &.mat-form-field-can-float 
      &.mat-form-field-should-float .mat-form-field-label,
      .mat-input-server:focus + .mat-form-field-label-wrapper .mat-form-field-label 
        @include _mat-form-field-outline-label-floating(
                $subscript-font-scale, $infix-padding + $outline-appearance-label-offset,
                $infix-margin-top);
      

      // Server-side rendered matInput with a label attribute but label not shown
      // (used as a pure CSS stand-in for mat-form-field-should-float).
      .mat-input-server[label]:not(:label-shown) + .mat-form-field-label-wrapper
      .mat-form-field-label 
        @include _mat-form-field-outline-label-floating(
                $subscript-font-scale, $infix-padding + $outline-appearance-label-offset,
                $infix-margin-top);
      
    
  

【参考方案4】：

您可以在 ma​​t-form-field 中添加 panelClass，如下所示：

您的 component.html：

 <mat-form-field panelClass="example-class"></mat-form-field>

并在全局css文件中设置样式

styles.scss：

.example-class

   height:40px