3.15

<?xml version="1.0" encoding="utf-8"?>
<androidx.constraintlayout.widget.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:background="#FFFFFF"
    tools:context=".stud">

    <TextView
        android:id="@+id/timeTextView"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:textSize="24sp"
        android:textStyle="bold"
        android:textColor="#808080"
        tools:ignore="MissingConstraints" />

    <ImageView
        android:id="@+id/addButton"
        android:layout_width="33dp"
        android:layout_height="19dp"
        android:layout_margin="16dp"
        android:layout_marginTop="16dp"
        android:layout_marginEnd="44dp"
        android:contentDescription="Add"
        android:src="@drawable/ic_add"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintTop_toTopOf="parent" />

    <TextView
        android:id="@+id/addHint"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="点击加号进行添加待办"
        android:textColor="#000000"
        android:textSize="8sp"
        app:layout_constraintEnd_toEndOf="@id/addButton"
        app:layout_constraintHorizontal_bias="0.659"
        app:layout_constraintStart_toStartOf="@id/addButton"
        app:layout_constraintTop_toBottomOf="@id/addButton" />

    <View
        android:id="@+id/backgroundView"
        android:layout_width="match_parent"
        android:layout_height="20dp"
        android:background="#87CEFA"
        app:layout_constraintTop_toBottomOf="@id/addHint"
        tools:layout_editor_absoluteX="-16dp" />


    <Button
        android:id="@+id/studyLogButton"
        android:layout_width="406dp"
        android:layout_height="44dp"
        android:layout_marginTop="4dp"
        android:background="@drawable/button_background"
        android:text="进行打卡/添加今日学习记录"
        android:textColor="#000000"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintHorizontal_bias="0.4"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toBottomOf="@id/backgroundView" />

    <Button
        android:id="@+id/viewTodoButton"
        android:layout_width="406dp"
        android:layout_height="44dp"
        android:layout_marginTop="4dp"
        android:background="@drawable/ic_back"
        android:text="查看今日待办"
        android:textColor="#000000"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintHorizontal_bias="0.4"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toBottomOf="@id/studyLogButton" />

    <Button
        android:id="@+id/statisticsButton"
        android:layout_width="406dp"
        android:layout_height="44dp"
        android:layout_marginTop="4dp"
        android:background="@drawable/button"
        android:text="统计本月打卡数"
        android:textColor="#000000"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintHorizontal_bias="0.4"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toBottomOf="@id/viewTodoButton" />

</androidx.constraintlayout.widget.ConstraintLayout>