修改课件部分逻辑

live_teaching/src/main/java/com/daya/live_teaching/widget/dialog/CoursewarePreviewDialog.java

@@ -56,6 +56,7 @@ public class CoursewarePreviewDialog extends Dialog implements View.OnClickListe
             @Override
             protected void convert(@NonNull BaseViewHolder holder, String imgPath) {
                 FrameLayout fl_container = holder.getView(R.id.fl_container);
+                fl_container.removeAllViews();
                 ImageView image = createImage(imgPath);
                 fl_container.addView(image, ViewGroup.LayoutParams.MATCH_PARENT, ViewGroup.LayoutParams.WRAP_CONTENT);
                 GlideUtils.INSTANCE.loadImage(getContext(), imgPath, image);