Android Studio - imageView 在设计编辑器中显示图像,但不在模拟器或设备上

Android Studio - imageView displaying image in design editor, but not on emulator or device

我正在尝试在此应用的 textView 上方显示图像,但它只会显示在 android studio 的设计编辑器中。我曾尝试将 XML 中的 srcCompat 更改为 src,尝试更改正在使用的图像,并尝试更改约束。问过朋友,不知道为什么会这样,完全不知所措

<?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:id="@+id/ConstraintLayout"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context=".MainActivity">

<ImageView
    android:id="@+id/questionPicture"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:adjustViewBounds="true"
    app:layout_constraintEnd_toEndOf="parent"
    app:layout_constraintStart_toStartOf="parent"
    app:layout_constraintTop_toTopOf="parent"
    tools:srcCompat="@tools:sample/backgrounds/scenic" />

<TextView
    android:id="@+id/questionsLeftNumber"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:layout_marginStart="8dp"
    android:layout_marginLeft="8dp"
    android:layout_marginBottom="8dp"
    android:text="99"
    android:textSize="48sp"
    android:textStyle="bold"
    app:layout_constraintBottom_toBottomOf="parent"
    app:layout_constraintStart_toStartOf="parent" />

<TextView
    android:id="@+id/questionsLeft"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:layout_marginStart="8dp"
    android:layout_marginLeft="8dp"
    android:text="Questions remaining"
    app:layout_constraintBottom_toBottomOf="@+id/questionsLeftNumber"
    app:layout_constraintStart_toEndOf="@+id/questionsLeftNumber"
    app:layout_constraintTop_toTopOf="@+id/questionsLeftNumber" />

<Button
    android:id="@+id/submit"
    style="@style/Widget.AppCompat.Button.Colored"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:layout_marginEnd="8dp"
    android:layout_marginRight="8dp"
    android:text="Submit"
    app:layout_constraintBottom_toBottomOf="@+id/questionsLeftNumber"
    app:layout_constraintEnd_toEndOf="parent"
    app:layout_constraintTop_toTopOf="@+id/questionsLeftNumber" />

<LinearLayout
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:layout_weight="1"
    android:orientation="vertical"
    app:layout_constraintEnd_toEndOf="parent"
    app:layout_constraintStart_toStartOf="parent"
    app:layout_constraintTop_toBottomOf="@+id/question">

    <LinearLayout
        android:id="@+id/linearLayout"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:orientation="horizontal">

        <Button
            android:id="@+id/answer2"
            style="@style/Widget.AppCompat.Button.Colored"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_weight="1"
            android:text="answer2" />

        <Button
            android:id="@+id/answer3"
            style="@style/Widget.AppCompat.Button.Colored"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_weight="1"
            android:text="answer3" />
    </LinearLayout>

    <LinearLayout
        android:id="@+id/linearLayout2"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:orientation="horizontal">

        <Button
            android:id="@+id/answer0"
            style="@style/Widget.AppCompat.Button.Colored"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_weight="1"
            android:text="answer0" />

        <Button
            android:id="@+id/answer1"
            style="@style/Widget.AppCompat.Button.Colored"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_weight="1"
            android:text="answer1" />
    </LinearLayout>
</LinearLayout>

<TextView
    android:id="@+id/question"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:layout_marginStart="8dp"
    android:layout_marginLeft="8dp"
    android:layout_marginTop="8dp"
    android:layout_marginEnd="8dp"
    android:layout_marginRight="8dp"
    android:fontFamily="sans-serif-black"
    android:text="Famous advice from an iconic mentor. Which fictional character really imparted this bit of sage wisdom?"
    android:textSize="18sp"
    app:layout_constraintEnd_toEndOf="parent"
    app:layout_constraintStart_toStartOf="parent"
    app:layout_constraintTop_toBottomOf="@+id/questionPicture" />
</androidx.constraintlayout.widget.ConstraintLayout>

What is displayed in android studio

What is displayed on either an emulator or device

tools:srcCompat="@tools:sample/backgrounds/scenic"

这仅适用于预览目的。 tools 命名空间中的属性仅在设计时启用并在编译时删除。

您应该改用 app:srcCompat