允许从设置界面跳回主页面

src/app/src/main/java/wificar/MyMainFrm.java

@@ -83,7 +83,6 @@ public class MyMainFrm extends Activity {
             intent.setClass(MyMainFrm.this, MyVideo.class);
             //通过Intent对象启动另外一个Activity
             startActivity(intent);
-            finish();
         });
 
         Button_set.setOnClickListener(v -> {
@@ -100,7 +99,6 @@ public class MyMainFrm extends Activity {
             intent.setClass(MyMainFrm.this, SettingsActivity.class);
             //通过Intent对象启动另外一个Activity
             startActivity(intent);
-            finish();
         });
 
     }

src/app/src/main/java/wificar/SettingsActivity.java

@@ -2,9 +2,12 @@ package wificar;
 
 import androidx.appcompat.app.AppCompatActivity;
 
+import android.content.Intent;
 import android.os.Bundle;
+import android.view.View;
 import android.view.Window;
 import android.view.WindowManager;
+import android.widget.Button;
 
 import my.wificar.R;
 
@@ -16,5 +19,8 @@ public class SettingsActivity extends AppCompatActivity {
         this.requestWindowFeature(Window.FEATURE_NO_TITLE);//隐去标题（应用的名字必须要写在setContentView之前，否则会有异常）
         this.getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN, WindowManager.LayoutParams.FLAG_FULLSCREEN);
         setContentView(R.layout.activity_settings);
+
+        Button back = findViewById(R.id.back);
+        back.setOnClickListener(view -> finish());
     }
 }