buildCoverImageSlot function

Widget buildCoverImageSlot(SlotBuildContext ctx, double width, double height)

构建封面图插槽的默认实现。 Builds the default cover image slot content.

监听封面 URL 和渲染状态，在播放器首帧渲染完成前显示封面图。 Listens to cover URL and render state; displays the cover image until the player has rendered its first frame.

Implementation

Widget buildCoverImageSlot(
  SlotBuildContext ctx,
  double width,
  double height,
) {
  return ListenableBuilder(
    listenable: Listenable.merge([
      ctx.controller.coverURLNotifier,
      ctx.controller.isRenderedNotifier,
    ]),
    builder: (buildContext, widget) {
      final coverUrl = ctx.controller.coverURLNotifier.value;
      final isRendered = ctx.controller.isRenderedNotifier.value;

      // 已渲染完成，或者没有封面，都不显示封面
      if (isRendered || coverUrl == null || coverUrl.isEmpty) {
        return const SizedBox.shrink();
      }

      return CoverImageWidget(
        imageUrl: coverUrl,
        width: width,
        height: height,
        fit: BoxFit.cover,
      );
    },
  );
}