在Dropzone中显示图像上载区域

Question

您好！ 我正在实现Dropzone.js来制作gallary。 我面临一个小问题。通过deafult，Dropzone显示空白容器区域，可点击效果上传一张或多张照片。但我想覆盖这种效果，并希望显示图像上传选项，如上面给出的图像。

到目前为止，我试图通过覆盖css来覆盖它，但结果是这样的。

我应该使用什么css代码来达到预期的效果？

dropzone.css

.dropzone, .dropzone * {
  box-sizing: border-box; }

.dropzone {
  min-height: 150px;
  border: 2px dotted rgba(0, 0, 0, 0.3);
  background: white;
  padding: 20px 20px; }
  .dropzone.dz-clickable {
    cursor: pointer; }
    .dropzone.dz-clickable  {
      cursor: default; }
    .dropzone.dz-clickable .dz-message, .dropzone.dz-clickable .dz-message * {
      cursor: pointer; 
      border: 2px dotted black;
    }
  .dropzone.dz-started .dz-message {
    display: none; }
  .dropzone.dz-drag-hover {
    border-style: solid; }
    .dropzone.dz-drag-hover .dz-message {
      opacity: 0.5; }
  .dropzone .dz-message {
    text-align: center;
    margin: 2em 0; }
  .dropzone .dz-preview {
      //border: 2px dotted grey;
    position: relative;
    display: inline-block;
    vertical-align: top;
    margin: 16px;
    min-height: 100px; }
    .dropzone .dz-preview:hover {
      z-index: 1000; }
      .dropzone .dz-preview:hover .dz-details {
        opacity: 1; }
    .dropzone .dz-preview.dz-file-preview .dz-image {
      border-radius: 20px;
      background: #999;
      background: linear-gradient(to bottom, #eee, #ddd); }
    .dropzone .dz-preview.dz-file-preview .dz-details {
      opacity: 1;

    }
    .dropzone .dz-preview.dz-image-preview {
     // background: yellow; 
    background: white;}
      .dropzone .dz-preview.dz-image-preview .dz-details {
        -webkit-transition: opacity 0.2s linear;
        -moz-transition: opacity 0.2s linear;
        -ms-transition: opacity 0.2s linear;
        -o-transition: opacity 0.2s linear;
        transition: opacity 0.2s linear; }
    .dropzone .dz-preview .dz-remove {
      font-size: 14px;
      text-align: center;
      display: block;
      cursor: pointer;
      border: none; }
      .dropzone .dz-preview .dz-remove:hover {
        text-decoration: underline; }
    .dropzone .dz-preview:hover .dz-details {
      opacity: 1; }
    .dropzone .dz-preview .dz-details {
      z-index: 20;
      position: absolute;
      top: 0;
      left: 0;
      opacity: 0;
      font-size: 13px;
      min-width: 100%;
      max-width: 100%;
      padding: 2em 1em;
      text-align: center;
      color: rgba(0, 0, 0, 0.9);
      line-height: 150%; }
      .dropzone .dz-preview .dz-details .dz-size {
        margin-bottom: 1em;
        font-size: 16px; }
      .dropzone .dz-preview .dz-details .dz-filename {
        white-space: nowrap; }
        .dropzone .dz-preview .dz-details .dz-filename:hover span {
          border: 1px solid rgba(200, 200, 200, 0.8);
          background-color: rgba(255, 255, 255, 0.8); }
        .dropzone .dz-preview .dz-details .dz-filename:not(:hover) {
          overflow: hidden;
          text-overflow: ellipsis; }
          .dropzone .dz-preview .dz-details .dz-filename:not(:hover) span {
            border: 1px solid transparent; }
      .dropzone .dz-preview .dz-details .dz-filename span, .dropzone .dz-preview .dz-details .dz-size span {
        background-color: rgba(255, 255, 255, 0.4);
        padding: 0 0.4em;
        border-radius: 3px; }
    .dropzone .dz-preview:hover .dz-image img {
      -webkit-transform: scale(1.05, 1.05);
      -moz-transform: scale(1.05, 1.05);
      -ms-transform: scale(1.05, 1.05);
      -o-transform: scale(1.05, 1.05);
      transform: scale(1.05, 1.05);
      -webkit-filter: blur(8px);
      filter: blur(8px); }
    .dropzone .dz-preview .dz-image {
      //border: 1px double grey;
      border-radius: 20px;
      overflow: hidden;
      width: 120px;
      height: 120px;
      position: relative;
      display: block;
      z-index: 10; }
      .dropzone .dz-preview .dz-image img {
        display: block; }
    .dropzone .dz-preview.dz-success .dz-success-mark {
      -webkit-animation: passing-through 3s cubic-bezier(0.77, 0, 0.175, 1);
      -moz-animation: passing-through 3s cubic-bezier(0.77, 0, 0.175, 1);
      -ms-animation: passing-through 3s cubic-bezier(0.77, 0, 0.175, 1);
      -o-animation: passing-through 3s cubic-bezier(0.77, 0, 0.175, 1);
      animation: passing-through 3s cubic-bezier(0.77, 0, 0.175, 1); }
    .dropzone .dz-preview.dz-error .dz-error-mark {
      opacity: 1;
      -webkit-animation: slide-in 3s cubic-bezier(0.77, 0, 0.175, 1);
      -moz-animation: slide-in 3s cubic-bezier(0.77, 0, 0.175, 1);
      -ms-animation: slide-in 3s cubic-bezier(0.77, 0, 0.175, 1);
      -o-animation: slide-in 3s cubic-bezier(0.77, 0, 0.175, 1);
      animation: slide-in 3s cubic-bezier(0.77, 0, 0.175, 1); }
    .dropzone .dz-preview .dz-success-mark, .dropzone .dz-preview .dz-error-mark {
      pointer-events: none;
      opacity: 0;
      z-index: 500;
      position: absolute;
      display: block;
      top: 50%;
      left: 50%;
      margin-left: -27px;
      margin-top: -27px; }
      .dropzone .dz-preview .dz-success-mark svg, .dropzone .dz-preview .dz-error-mark svg {
        display: block;
        width: 54px;
        height: 54px; }
    .dropzone .dz-preview.dz-processing .dz-progress {
      opacity: 1;
      -webkit-transition: all 0.2s linear;
      -moz-transition: all 0.2s linear;
      -ms-transition: all 0.2s linear;
      -o-transition: all 0.2s linear;
      transition: all 0.2s linear; }
    .dropzone .dz-preview.dz-complete .dz-progress {
      opacity: 0;
      -webkit-transition: opacity 0.4s ease-in;
      -moz-transition: opacity 0.4s ease-in;
      -ms-transition: opacity 0.4s ease-in;
      -o-transition: opacity 0.4s ease-in;
      transition: opacity 0.4s ease-in; }
    .dropzone .dz-preview:not(.dz-processing) .dz-progress {
      -webkit-animation: pulse 6s ease infinite;
      -moz-animation: pulse 6s ease infinite;
      -ms-animation: pulse 6s ease infinite;
      -o-animation: pulse 6s ease infinite;
      animation: pulse 6s ease infinite; }
    .dropzone .dz-preview .dz-progress {
      opacity: 1;
      z-index: 1000;
      pointer-events: none;
      position: absolute;
      height: 16px;
      left: 50%;
      top: 50%;
      margin-top: -8px;
      width: 80px;
      margin-left: -40px;
      background: rgba(255, 255, 255, 0.9);
      -webkit-transform: scale(1);
      border-radius: 8px;
      overflow: hidden; }
      .dropzone .dz-preview .dz-progress .dz-upload {

        background: #333;
        background: linear-gradient(to bottom, #666, #444);
        position: absolute;
        top: 0;
        left: 0;
        bottom: 0;
        width: 0;
        -webkit-transition: width 300ms ease-in-out;
        -moz-transition: width 300ms ease-in-out;
        -ms-transition: width 300ms ease-in-out;
        -o-transition: width 300ms ease-in-out;
        transition: width 300ms ease-in-out; }
    .dropzone .dz-preview.dz-error .dz-error-message {
      display: block; }
    .dropzone .dz-preview.dz-error:hover .dz-error-message {
      opacity: 1;
      pointer-events: auto; }
    .dropzone .dz-preview .dz-error-message {
      pointer-events: none;
      z-index: 1000;
      position: absolute;
      display: block;
      display: none;
      opacity: 0;
      -webkit-transition: opacity 0.3s ease;
      -moz-transition: opacity 0.3s ease;
      -ms-transition: opacity 0.3s ease;
      -o-transition: opacity 0.3s ease;
      transition: opacity 0.3s ease;
      border-radius: 8px;
      font-size: 13px;
      top: 130px;
      left: -10px;
      width: 140px;
      background: #be2626;
      background: linear-gradient(to bottom, #be2626, #a92222);
      padding: 0.5em 1.2em;
      color: white; }
      .dropzone .dz-preview .dz-error-message:after {
        content: '';
        position: absolute;
        top: -6px;
        left: 64px;
        width: 0;
        height: 0;
        border-left: 6px solid transparent;
        border-right: 6px solid transparent;
        border-bottom: 6px solid #be2626; }

Answer 1

在HTML上，只需在div中包含指定给dropzone的表单元素，如：

<div id="wrapper">
   <form action="/file-upload"
                 class="dropzone"
                 id="my-awesome-dropzone">
   </form>
</div>

然后将图像分配给css上的包装div：

  #wrapper{
    background-image: url(dropText.png);
    background-position: center;
    background-repeat: no-repeat;
    width: 100%;
    height: 15em;
    border: 2px dashed #ccc;
    padding: 0px 0px;
    margin: 20px auto;
    opacity: 0.8;
  }

  #wrapper:hover{
    -moz-transition: background-image 0.4s  ease-in-out 1s;
    -webkit-transition: background-image 0.4s  ease-in-out 1s;
    -ms-transition: background-image 0.4s  ease-in-out 1s;
    -o-transition: background-image 0.4s  ease-in-out 1s;
    background-image: url(uploadPic.png);
    opacity: 1;
  }

记得也要改变形式不透明度：

#my-awesome-dropzone{
    position: relative;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    opacity: 0;
  }