如何在Angular 6材质中更改文本框占位符颜色

Question

Angular 6 material code.

<mat-form-field>
    <input matInput placeholder="Input">
  </mat-form-field>

I wanted to change default color when input element get focused.

I have already tired this. How do i change md-input-container placeholder color using css in angular material

nothing seems work.

Answer 1

If i understand your question this css should work.

  .mat-focused .mat-form-field-label {
      /*change color of label*/
      color: red !important;
  }

 .mat-form-field-underline {
   /*change color of underline*/
    background-color: blue !important;
 } 

.mat-form-field-ripple {
   /*change color of underline when focused*/
   background-color: yellow !important;;
 } 

Hope it was useful.

Answer 2

For Angular 7 and Material 7, this worked for me:

/* Placeholder overrides */
:host ::ng-deep input::-webkit-input-placeholder {
    color: rgba(255,255,255, 0.7) !important;
}

:host ::ng-deep input:-moz-placeholder { /* Firefox 18- */
    color: rgba(255,255,255, 0.7) !important;
}

:host ::ng-deep input::-moz-placeholder {  /* Firefox 19+ */
    color: rgba(255,255,255, 0.7) !important;
}

:host ::ng-deep input:-ms-input-placeholder {
    color: rgba(255,255,255, 0.7) !important;
}

For the underline, I used an outline styled input but you can just change the class used.

/* Appearance around each input/button to remove faded outline 
but put the dark hover back in */
::ng-deep .mat-form-field-appearance-outline .mat-form-field-outline {
    color: transparent !important;
}
::ng-deep .mat-form-field-appearance-outline .mat-form-field-outline-thick {
    color: rgba(255, 255, 255, 0.87) !important;
}

While I don't think this is the best way of doing it, especially using ::ng-deep, it's the only thing that works right now for a specific component, for me.