When you set the text of this custom label the text size is automatically modified to the largest possible size so that all the text is visible. To use this view in your project, you should take the AutoTextSizeLabel class from the attached example and add it to your project. You should then...
Take a look at the first column in the attached screenshot. It keeps the label width the same. It adjusts the size of the text to fit the label. Isn't that what you want There might be other solutions, if this is not suitable. If you want to keep the text in the same line, in the designer customview you check 'Single Line'