[cordova-tools] Error processing "attach": Error: Unable to find adb. Please ensure it is in your PATH and re-open Visual Studio Code

I’m using visual studio code to build my ionic3 app , now to want to debug my project then I have this error :
[cordova-tools] Error processing “attach”: Error: Unable to find adb. Please ensure it is in your PATH and re-open Visual Studio Code

how can I fix it ?

any one can help me ?