對于有些大點的Gif在低端機上加載可能會需要點時間，所以我們可以加個回調(diào)加個彈框會友好點

   showPleaseDialog("加載中...");
                    Glide.with(getApplicationContext())
                            .load(GlobalPath
                                    .RES_IMAGE + template_images_preview[postion - 1])
                            .into(new GlideDrawableImageViewTarget(iv_preview) {

                                @Override
                                public void onResourceReady(GlideDrawable resource, GlideAnimation<? super GlideDrawable> animation) {
                                    super.onResourceReady(resource, animation);
                                    dismiss();
                                }
                            });