Q: If you want to change the text color of the layer, the buttons in the text style group of Style Settings tab are all grey. How do you do that?

A: The text layer is different from the point, line, and region layers. The style is stored in the text object, so you need to perform two steps before modifying the text style: 1. Set the text layer editable; 2. Select the text object to be modified the style. You can either select one or select all the text objects, and then click the corresponding button in the text style group.