我有一個背景圖像，我正在著色和下載的顏色，當我下載所有我看到的是顏色，因為背景圖像是透明的，它的模板由于某種原因沒有保存。 代碼如下:

const colorPicker = document.getElementById('colorPicker');
const fileInput = document.getElementById('fileInput');
const uploadedImage = document.getElementById('uploadedImage');
const tshirt = document.getElementById('tshirt');
const sizeRange = document.getElementById('sizeRange');
const saveButton = document.getElementById('saveButton');
// Update the t-shirt color on color change
colorPicker.addEventListener('change', function() {
  tshirt.style.backgroundColor = colorPicker.value;
});

// Update the uploaded image
fileInput.addEventListener('change', function() {
  const file = fileInput.files[0];
  const reader = new FileReader();

  reader.onload = function(e) {
    uploadedImage.src = e.target.result;
  };

  reader.readAsDataURL(file);
});
// Save the background image with the file displayed on the shirt
saveButton.addEventListener('click', function() {
  html2canvas(tshirt).then(function(canvas) {
    const context = canvas.getContext('2d');

    context.drawImage(uploadedImage, uploadedImage.offsetLeft, uploadedImage.offsetTop);

    const combinedImageURL = canvas.toDataURL('image/png');
    const link = document.createElement('a');
    link.href = combinedImageURL;
    link.download = 'combined_image.png';
    link.click();
  });
});

/* CSS styling for the t-shirt */

#tshirt {
  width: 450px;
  height: 545px;
  background-image: url('https://ourcodeworld.com/public-media/gallery/gallery-5d5afd3f1c7d6.png');
  background-size: contain;
  background-repeat: no-repeat;
  position: relative;
  margin: 50px auto;
  text-align: center;
}


/* CSS styling for the color selection */

#colorPicker {
  margin-top: 20px;
}


/* CSS styling for the file upload */

#fileInput {
  margin-top: 20px;
}

<script src="https://cdnjs.cloudflare.com/ajax/libs/html2canvas/1.4.0/html2canvas.min.js"></script>
<div id="tshirt">
  <img id="uploadedImage" src="#" alt="Uploaded Image" class="draggable" style="max-width: 80%; max-height: 80%;" />
</div>
<input type="color" id="colorPicker" />
<input type="file" id="fileInput" />
<button id="saveButton">Save</button>