ADD file via upload

Hello_GudieActivity.java

@@ -0,0 +1,50 @@
+package com.example.final_project_app;
+
+import android.content.Intent;
+import android.os.Bundle;
+import android.widget.TextView;
+import android.os.CountDownTimer;
+import androidx.appcompat.app.AppCompatActivity;
+
+public class Hello_GudieActivity extends AppCompatActivity {
+    public TextView djs;
+    private android.os.CountDownTimer countDownTimer;
+    private long timeLeftInMillis =6000;
+    private boolean CountDownTimer;
+
+    @Override
+    protected void onCreate(Bundle savedInstanceState) {
+        super.onCreate(savedInstanceState);
+        setContentView(R.layout.activity_hello_gudie);
+        djs = findViewById(R.id.djs);
+        //启动倒计时
+        startCountdown();
+    }
+    private void startCountdown() {
+        countDownTimer =new CountDownTimer(timeLeftInMillis,1000) {
+            @Override
+            public void onTick(long millisUntilFinished) {
+                timeLeftInMillis = millisUntilFinished;
+                int secondsRemaining = (int) (millisUntilFinished / 1000);
+                djs.setText(secondsRemaining +" s");
+            }
+
+            @Override
+            public void onFinish() {
+                //跳转界面
+                startActivity(new Intent(Hello_GudieActivity.this,login.class));
+                // 倒计时结束后跳转到哪个界面
+                finish();
+
+            }
+        }.start();
+    }
+
+    @Override
+    protected void onDestroy() {
+        super.onDestroy();
+        if (countDownTimer != null){
+            countDownTimer.cancel();
+        }
+    }
+}