ボタンを縦方向で中央揃えした

app/build.gradle

@@ -33,8 +33,9 @@ dependencies {
     implementation 'androidx.appcompat:appcompat:1.6.1'
     implementation 'com.google.android.material:material:1.5.0'
     implementation 'androidx.constraintlayout:constraintlayout:2.1.4'
+
+
     testImplementation 'junit:junit:4.13.2'
     androidTestImplementation 'androidx.test.ext:junit:1.1.5'
     androidTestImplementation 'androidx.test.espresso:espresso-core:3.5.1'
-    implementation 'com.journeyapps:zxing-android-embedded:4.3.0'
 }

app/src/main/java/com/example/childguard/QRFragment.java

@@ -1,18 +1,13 @@
 package com.example.childguard;
 
-import android.content.Intent;
 import android.os.Bundle;
 
 import androidx.fragment.app.Fragment;
 
-import android.util.Log;
 import android.view.LayoutInflater;
 import android.view.View;
 import android.view.ViewGroup;
 
-import com.google.zxing.integration.android.IntentIntegrator;
-import com.google.zxing.integration.android.IntentResult;
-
 /**
  * A simple {@link Fragment} subclass.
  * Use the {@link QRFragment#newInstance} factory method to
@@ -54,12 +49,11 @@ public class QRFragment extends Fragment {
     @Override
     public void onCreate(Bundle savedInstanceState) {
         super.onCreate(savedInstanceState);
-        new IntentIntegrator(getActivity()).initiateScan();//QRカメラ起動
+        if (getArguments() != null) {
+            mParam1 = getArguments().getString(ARG_PARAM1);
+            mParam2 = getArguments().getString(ARG_PARAM2);
+        }
     }
-
-
-        //QRカメラから受け取った引数の処理
-
 
     @Override
     public View onCreateView(LayoutInflater inflater, ViewGroup container,
@@ -67,5 +61,4 @@ public class QRFragment extends Fragment {
         // Inflate the layout for this fragment
         return inflater.inflate(R.layout.fragment_qr, container, false);
     }
-
 }

app/src/main/res/layout/fragment_home.xml

@@ -72,21 +72,21 @@
 
     <FrameLayout
         android:layout_width="match_parent"
-        android:layout_height="wrap_content"
+        android:layout_height="match_parent"
         android:layout_marginLeft="20dp"
         android:layout_marginRight="20dp"
         android:background="@drawable/frame_style_button">
 
         <Button
             android:layout_width="match_parent"
-            android:layout_height="match_parent"
+            android:layout_height="wrap_content"
+            android:layout_gravity="center"
             android:layout_marginLeft="20dp"
-            android:layout_marginTop="75dp"
             android:layout_marginRight="20dp"
+            android:backgroundTint="#778899"
             android:text="QRコード印刷"
             android:textColor="@color/white"
-            android:textSize="40dp"
-            android:backgroundTint="#778899"/>
+            android:textSize="40dp" />
         <!--<ImageView
             android:layout_width="wrap_content"
             android:layout_height="wrap_content"