The RadFluidContentControl has three content properties, only one of which is visible at any given time. The way the visible content is changed is determined by the four available threshold properties. The names of these threshold properties are hopefully descriptive enough and signify the transition between two contents. E.g. the SmallToNormalThreshold is used to determine when the normal content will be shown, in the cases when the SmallContent is currently visible. Alternatively, the NormalToSmallThreshold property controls when the normal content will be hidden and the SmallContent shown. I will give a brief example:
Let's say you have three visual elements that you want to show depending on the available space - SmallContent(200x200px), NormalContent(400x400px), LargeContent(600x600px). We set the FluidContentControl's corrsponding properties to hold our visual elements. Next, we need to set the threshold properties. Below are suitable values with brief explanations:
SmallToNormalThreshold - (400, 400): we set it to the size of our normal content, which means that as soon as enough space is available to render our normal content, it will be shown. This threshold is used when there is relatively little available space and our small content is shown and the available space increases - when the space reaches the threshold, the normal content is displayed and the SmallContent is hidden.
NormalToSmallThreshold - (399, 399): we set it to a size that is smaller than the SmallToNormalThreshold in order to avoid ambiguous situations. This threshold is used when the normal content is visible and the available space is decreasing. Thus, we set this threshold to a value just below the size of our normal content, which will hide it as soon as the available size is not enough to properly render the normal content.
NormalToLargeThreshold - (600, 600): the reasoning here is the same as for the SmallToNormalContent.
LargeToNormalContent - (599, 599): the reasoning here is the same as for the NormalToSmallContent.
In case you need to specify only the width or height of a threshold, you can set the other value to 0 - this way it will be disregarded. Also, you are by no means restricted to use the RadFluidContentControl within a RadtileView.
In the Q3 release we added a ContentChangeMode property which allows you to manually change the State of the control, and thus the visible content. When you set the property to "Manual", the thresholds are not considered and you are responsible for switching the visible content. Setting the property to "Automatic" makes the control use the thresholds instead.
I hope I was able to make things clearer. Let me know if you have any questions.
the Telerik team