如何使進度條始終位於滾動視圖的中心屏幕和滑動刷新布局？

Question

我有這樣的視圖層次結構：

這是我的 xml：

<androidx.constraintlayout.widget.ConstraintLayout
        xmlns:app="http://schemas.android.com/apk/res-auto"
        xmlns:tools="http://schemas.android.com/tools" xmlns:android="http://schemas.android.com/apk/res/android"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:id="@+id/constraintLayout_profile">


    <androidx.swiperefreshlayout.widget.SwipeRefreshLayout
            android:layout_width="0dp"
            android:layout_height="0dp"
            app:layout_constraintEnd_toEndOf="parent"
            app:layout_constraintStart_toStartOf="parent"
            app:layout_constraintBottom_toBottomOf="parent"
            app:layout_constraintTop_toTopOf="parent" android:id="@+id/swipeRefreshLayout_userControl">


        <androidx.core.widget.NestedScrollView
                android:layout_width="match_parent"
                android:layout_height="0dp"
                android:background="@android:color/white"
                android:id="@+id/scrollView_user_control"
                app:layout_constraintStart_toStartOf="parent" app:layout_constraintEnd_toEndOf="parent"
                app:layout_constraintTop_toTopOf="parent"
                app:layout_constraintBottom_toBottomOf="parent">

            <androidx.constraintlayout.widget.ConstraintLayout
                    android:layout_width="match_parent"
                    android:layout_height="match_parent">

                <de.hdodenhof.circleimageview.CircleImageView
                        android:id="@+id/imageView_profile_image_user_information"
                        android:layout_width="80dp"
                        android:layout_height="80dp"
                        android:src="@drawable/user"
                        app:civ_border_width="0.5dp"
                        app:civ_border_color="#FF000000" android:layout_marginEnd="8dp"
                        app:layout_constraintEnd_toEndOf="parent"
                        android:layout_marginStart="8dp" app:layout_constraintStart_toStartOf="parent"
                        android:layout_marginTop="16dp" app:layout_constraintTop_toTopOf="parent"/>
                <TextView
                        android:text="User Fullname"
                        android:layout_width="wrap_content"
                        android:layout_height="wrap_content"
                        android:id="@+id/textView_user_fullname_user_information" android:layout_marginTop="16dp"
                        app:layout_constraintTop_toBottomOf="@+id/imageView_profile_image_user_information"
                        app:layout_constraintEnd_toEndOf="parent" android:layout_marginEnd="8dp"
                        app:layout_constraintStart_toStartOf="parent" android:layout_marginStart="8dp"
                        android:textSize="18sp"/>
                <TextView
                        android:text="user@email.com"
                        android:layout_width="wrap_content"
                        android:layout_height="wrap_content"
                        android:id="@+id/textView_user_email_user_information" app:layout_constraintEnd_toEndOf="parent"
                        android:layout_marginEnd="8dp"
                        app:layout_constraintStart_toStartOf="parent" android:layout_marginStart="8dp"
                        app:layout_constraintTop_toBottomOf="@+id/textView_user_fullname_user_information"
                        android:layout_marginTop="8dp"/>
                <TextView
                        android:text="AKAN DIHADIRI"
                        android:layout_width="0dp"
                        android:layout_height="35dp"
                        android:id="@+id/textView_will_come_user_information" app:layout_constraintStart_toStartOf="parent"
                        app:layout_constraintEnd_toEndOf="parent" android:layout_marginTop="16dp"
                        app:layout_constraintTop_toBottomOf="@+id/textView_user_email_user_information"
                        android:gravity="center|left"
                        android:paddingStart="16dp" android:background="#D2D1D6"/>

                <ImageView
                        android:src="@drawable/ic_settings"
                        android:layout_width="30dp"
                        android:layout_height="30dp"
                        android:id="@+id/imageView_gear_setting_user_information"
                        app:layout_constraintTop_toTopOf="@+id/imageView_profile_image_user_information"
                        app:layout_constraintEnd_toEndOf="parent" android:layout_marginEnd="24dp"/>

                <androidx.recyclerview.widget.RecyclerView
                        android:layout_width="0dp"
                        android:layout_height="wrap_content"
                        android:scrollbars="vertical"
                        app:layout_constraintTop_toBottomOf="@+id/textView_will_come_user_information"
                        app:layout_constraintBottom_toBottomOf="parent"
                        app:layout_constraintEnd_toEndOf="parent"
                        app:layout_constraintStart_toStartOf="parent"
                        tools:listitem="@layout/item_general_event"
                        android:id="@+id/recyclerView_attended_event_user_control"
                        app:layout_constraintHorizontal_bias="1.0"
                        android:nestedScrollingEnabled="false">
                </androidx.recyclerview.widget.RecyclerView>

                <ImageView
                        android:id="@+id/imageView_verified_icon"
                        android:layout_width="20dp"
                        android:layout_height="20dp"
                        android:layout_marginTop="4dp"
                        android:layout_marginEnd="4dp"
                        app:layout_constraintEnd_toEndOf="@+id/imageView_profile_image_user_information"
                        app:layout_constraintTop_toTopOf="@+id/imageView_profile_image_user_information"
                        app:srcCompat="@drawable/verifiedicon" />


            </androidx.constraintlayout.widget.ConstraintLayout>


        </androidx.core.widget.NestedScrollView>

        <ProgressBar
                android:id="@+id/progressBar_user_control"
                style="?android:attr/progressBarStyle"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:visibility="visible" />


    </androidx.swiperefreshlayout.widget.SwipeRefreshLayout>





</androidx.constraintlayout.widget.ConstraintLayout>

如您所見，我的滾動視圖中有回收器視圖，還有一個滑動刷新布局將其全部包裹起來。

我希望我的進度條始終位於屏幕中央。 我試圖從這里閱讀： How to make a ProgressBar留在屏幕中心盡管滾動。 據說

您需要 ScrollView 與布局中的 ProgressDialog 處於同一級別

我試圖實現它，如上圖，但我不知道為什么我的進度條不會出現在屏幕上。

如果我將進度條放在滾動視圖中，如下所示：

進度條會出現，但不會出現在屏幕中央。 這取決於我的回收站視圖中的項目數量。 那么如何解決這個問題呢？

Answer 1

將ProgressBar放在外部ConstraintLayout的底部。 檢查以下：

<androidx.constraintlayout.widget.ConstraintLayout
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools" xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:id="@+id/constraintLayout_profile">


    <androidx.swiperefreshlayout.widget.SwipeRefreshLayout
        android:layout_width="0dp"
        android:layout_height="0dp"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintBottom_toBottomOf="parent"
        app:layout_constraintTop_toTopOf="parent" android:id="@+id/swipeRefreshLayout_userControl">


        <androidx.core.widget.NestedScrollView
            android:layout_width="match_parent"
            android:layout_height="0dp"
            android:background="@android:color/white"
            android:id="@+id/scrollView_user_control"
            app:layout_constraintStart_toStartOf="parent" app:layout_constraintEnd_toEndOf="parent"
            app:layout_constraintTop_toTopOf="parent"
            app:layout_constraintBottom_toBottomOf="parent">

            <androidx.constraintlayout.widget.ConstraintLayout
                android:layout_width="match_parent"
                android:layout_height="match_parent">

                <de.hdodenhof.circleimageview.CircleImageView
                    android:id="@+id/imageView_profile_image_user_information"
                    android:layout_width="80dp"
                    android:layout_height="80dp"
                    android:src="@drawable/user"
                    app:civ_border_width="0.5dp"
                    app:civ_border_color="#FF000000" android:layout_marginEnd="8dp"
                    app:layout_constraintEnd_toEndOf="parent"
                    android:layout_marginStart="8dp" app:layout_constraintStart_toStartOf="parent"
                    android:layout_marginTop="16dp" app:layout_constraintTop_toTopOf="parent"/>
                <TextView
                    android:text="User Fullname"
                    android:layout_width="wrap_content"
                    android:layout_height="wrap_content"
                    android:id="@+id/textView_user_fullname_user_information" android:layout_marginTop="16dp"
                    app:layout_constraintTop_toBottomOf="@+id/imageView_profile_image_user_information"
                    app:layout_constraintEnd_toEndOf="parent" android:layout_marginEnd="8dp"
                    app:layout_constraintStart_toStartOf="parent" android:layout_marginStart="8dp"
                    android:textSize="18sp"/>
                <TextView
                    android:text="user@email.com"
                    android:layout_width="wrap_content"
                    android:layout_height="wrap_content"
                    android:id="@+id/textView_user_email_user_information" app:layout_constraintEnd_toEndOf="parent"
                    android:layout_marginEnd="8dp"
                    app:layout_constraintStart_toStartOf="parent" android:layout_marginStart="8dp"
                    app:layout_constraintTop_toBottomOf="@+id/textView_user_fullname_user_information"
                    android:layout_marginTop="8dp"/>
                <TextView
                    android:text="AKAN DIHADIRI"
                    android:layout_width="0dp"
                    android:layout_height="35dp"
                    android:id="@+id/textView_will_come_user_information" app:layout_constraintStart_toStartOf="parent"
                    app:layout_constraintEnd_toEndOf="parent" android:layout_marginTop="16dp"
                    app:layout_constraintTop_toBottomOf="@+id/textView_user_email_user_information"
                    android:gravity="center|left"
                    android:paddingStart="16dp" android:background="#D2D1D6"/>

                <ImageView
                    android:src="@drawable/ic_settings"
                    android:layout_width="30dp"
                    android:layout_height="30dp"
                    android:id="@+id/imageView_gear_setting_user_information"
                    app:layout_constraintTop_toTopOf="@+id/imageView_profile_image_user_information"
                    app:layout_constraintEnd_toEndOf="parent" android:layout_marginEnd="24dp"/>

                <androidx.recyclerview.widget.RecyclerView
                    android:layout_width="0dp"
                    android:layout_height="wrap_content"
                    android:scrollbars="vertical"
                    app:layout_constraintTop_toBottomOf="@+id/textView_will_come_user_information"
                    app:layout_constraintBottom_toBottomOf="parent"
                    app:layout_constraintEnd_toEndOf="parent"
                    app:layout_constraintStart_toStartOf="parent"
                    tools:listitem="@layout/item_general_event"
                    android:id="@+id/recyclerView_attended_event_user_control"
                    app:layout_constraintHorizontal_bias="1.0"
                    android:nestedScrollingEnabled="false">
                </androidx.recyclerview.widget.RecyclerView>

                <ImageView
                    android:id="@+id/imageView_verified_icon"
                    android:layout_width="20dp"
                    android:layout_height="20dp"
                    android:layout_marginTop="4dp"
                    android:layout_marginEnd="4dp"
                    app:layout_constraintEnd_toEndOf="@+id/imageView_profile_image_user_information"
                    app:layout_constraintTop_toTopOf="@+id/imageView_profile_image_user_information"
                    app:srcCompat="@drawable/verifiedicon" />


            </androidx.constraintlayout.widget.ConstraintLayout>
        </androidx.core.widget.NestedScrollView>
    </androidx.swiperefreshlayout.widget.SwipeRefreshLayout>

    <ProgressBar
        android:id="@+id/progressBar_user_control"
        style="?android:attr/progressBarStyle"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintTop_toTopOf="parent"
        app:layout_constraintBottom_toBottomOf="parent"
        android:visibility="visible" />

</androidx.constraintlayout.widget.ConstraintLayout>