Ngay cả những hệ thống phân cấp tốt nhất-crafted sẽ phá vỡ nếu có những yếu tố quá nhiều. Đặt mục ở gần đỉnh không phải luôn luôn quan trọng để thiết lập hệ thống phân cấp trực quan; dòng chảy công việc và mối quan hệ với các yếu tố khác cũng phải được xem xét. | problematic given that mobile users typically want quick access to maps. To avoid these user experience issues make sure your hierarchy matches user needs within the relevant context. And more important make sure that every element you choose is essential for the user experience. Even the most well-crafted hierarchy will break down if there are too many elements. Placing items near the top is not always key to establishing visual hierarchy the task flow and relationship to other elements must also be considered. For example Twitterific lets users add contacts images and location information to their Tweets FIGURE . Although these options are near the top they may be overlooked since the cursor focus is in the text area. Also the header is typically used for navigation so users may not expect additional options in that area. In contrast on TweetDeck FIGURE the Tweet options are in the lower-right portion of the Tweet form supporting the natural workflow. FIGURE Twitterific Tweet form FIGURE TweetDeck Tweet form Scale Scale is another way to establish visual hierarchy. In essence larger visual elements attract the eye more than smaller ones. FIGURE illustrates how Thermometer uses large text combined with a bright blue background to emphasize the temperature. Its place in the visual hierarchy is reinforced through contrast. Other elements such as the City Condition Wind and Unit have smaller type with a subdued blue background. Both groupings occupy the same space but the temperature is bigger. Scale can also establish hierarchy within visual groupings. For example All Recipes uses scale and color to draw attention to the recipe name photo and rating FIGURE . In contrast the recipe author is displayed in smaller type 228 CHAPTER 10 VISUAL DESIGN Download from suggesting that this information is less important. This makes sense within this context it s unlikely that users will know the author but a different scale .