# Android_Review_1_plus Toast & extract res/val/string & default import hotkey ![](https://raw.githubusercontent.com/QueenieCplusplus/Android_Review_1_plus/main/27.output%203.png) layout see: <?xml version="1.0" encoding="utf-8"?> <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" android:layout_width="match_parent" android:layout_height="wrap_content" xmlns:tools="http://schemas.android.com/tools" android:orientation="vertical" android:layout_gravity="center_vertical" tools:context=".MainActivity"> <TextView android:layout_width="wrap_content" android:layout_height="wrap_content" android:layout_gravity="center_horizontal" android:textSize="30sp" android:text="@string/txt1" /> <Button android:id="@+id/btn" android:layout_width="wrap_content" android:layout_height="wrap_content" android:layout_gravity="center_horizontal" android:text="@string/btn1" /> </LinearLayout> code see: package com.example.kateskotlinandroid2021 import androidx.appcompat.app.AppCompatActivity import android.os.Bundle import android.widget.Button import android.widget.Toast class MainActivity : AppCompatActivity() { override fun onCreate(savedInstanceState: Bundle?) { super.onCreate(savedInstanceState) setContentView(R.layout.activity_main) // inside onCreate() and after setContentView val KButton: Button = findViewById(R.id.btn) KButton.setOnClickListener{ afterClick()} } private fun afterClick() { Toast.makeText(this, "Welcome to 2021, Dear Kate!", Toast.LENGTH_SHORT).show() } } * build gradle at module level, not project level. ![](https://raw.githubusercontent.com/QueenieCplusplus/Android_Review_1_plus/main/2.module%20level%20build%20gradle.png) * attrs in Layout ![](https://raw.githubusercontent.com/QueenieCplusplus/Android_Review_1_plus/main/16.add%20gravity%20attrs.png) * debug ![](https://raw.githubusercontent.com/QueenieCplusplus/Android_Review_1_plus/main/24.debug.png) * hot key ( opt + enter ) * extract string value ![](https://raw.githubusercontent.com/QueenieCplusplus/Android_Review_1_plus/main/11.opt%20%2B%20enter%20%3D%20extract%20string.png) * defaultly import modules ![](https://raw.githubusercontent.com/QueenieCplusplus/Android_Review_1_plus/main/21.opt%20%2B%20enter%20%3D%20import%20default.png) * project see https://github.com/QueenieCplusplus/Android_Review_1_plus/tree/main/KatesKotlinAndroid2021