Congratulations! You just created a GUI that is able to modify the layer stack in several ways. In this chapter we learned how to create a simple but fully operational layer tree. We also gained some valuable insight into JavaScript. You might have been familiar with most of the concepts discussed in this chapter. Or, this chapter might have taught you lots of new things. If this is the case, take some rest. You are on your way to not only mastering OpenLayers 3 but also becoming a great frontend developer.
We went through a small subset of the valid compatibility issues with Internet Explorer. It has been developed in its own way for quite a long time, causing quite a lot nuisance for frontend developers. However, most of these problems do not persist in Microsoft Edge.
In the next chapter, we will discuss various vector-data-based concepts. We will take a look at how we can manage vector data effectively by validating attributes, creating input forms, constraining feature types,...