参考：http://stackoverflow.com/questions/33164886/android-textview-do-not-concatenate-text-displayed-with-settext

在Activity中对TextView进行动态更新显示数据时，如果使用:

RGB_textview.setText(settingData.Image_R + "," + settingData.Image_G + "," + settingData.Image_B);

则Android Studio 会提示：“Do not concatenate text displayed with setText，use resource string with placeholders”，

应改为：

RGB_textview.setText(getString(R.string.RGB_value_string, settingData.Image_R, settingData.Image_G, settingData.Image_B));
<string name="RGB_value_string">%1$d,%2$d,%3$d</string>

不修改也能正常运行，但修改一下会更加规范。

常用格式:
%n$s--->n表示目前是第几个参数 （比如%1$s中的1代表第一个参数）,s代表字符串
%n$d--->n表示目前是第几个参数 （比如%1$d中的1代表第一个参数）,d代表整数
%n$f--->n表示目前是第几个参数 （比如%1$f中的1代表第一个参数）,f代表浮点数

When calling TextView#setText:

• Never call Number#toString() to format numbers; it will not handle fraction separators and locale-specific digits properly. Consider using String#format with proper format specifications (%d or %f) instead.
• Do not pass a string literal (e.g. "Hello") to display text. Hardcoded text can not be properly translated to other languages. Consider using Android resource strings instead.
• Do not build messages by concatenating text chunks. Such messages can not be properly translated.
  
  来源： https://stackoverflow.com/questions/33164886/android-textview-do-not-concatenate-text-displayed-with-settext

Android TextView : “Do not concatenate text displayed with setText”