Android开发,用Kotlin语言编程。以下是一个layout文件:
<?xml version="1.0" encoding="utf-8"?><androidx.constraintlayout.widget.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android" android:layout_width="match_parent" android:layout_height="match_parent" android:id="@+id/loginLayout" xmlns:app="http://schemas.android.com/apk/res-auto">
<TextView
android:id="@+id/accountLabel"
android:layout_width="0dp"
android:layout_height="wrap_content"
android:textSize="18sp"
android:text="Account:"
app:layout_constraintEnd_toStartOf="@+id/accountEdit"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="parent"
app:layout_constraintVertical_bias="0.1"
android:layout_marginEnd="8dp" />
<EditText
android:id="@+id/accountEdit"
android:layout_width="0dp"
android:layout_height="48dp"
android:layout_marginTop="16dp"
android:hint="Enter your account"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toEndOf="@+id/accountLabel"
app:layout_constraintTop_toTopOf="@+id/accountLabel"
app:layout_constraintHorizontal_bias="0"
android:layout_marginStart="8dp" />
<TextView
android:id="@+id/passwordLabel"
android:layout_width="0dp"
android:layout_height="wrap_content"
android:textSize="18sp"
android:text="Password:"
app:layout_constraintEnd_toStartOf="@+id/passwordEdit"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toBottomOf="@+id/accountEdit"
app:layout_constraintVertical_bias="0.1"
android:layout_marginEnd="8dp" />
<EditText
android:id="@+id/passwordEdit"
android:layout_width="0dp"
android:layout_height="48dp"
android:layout_marginTop="16dp"
android:inputType="textPassword"
android:hint="Enter your password"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toEndOf="@+id/passwordLabel"
app:layout_constraintTop_toTopOf="@+id/passwordLabel"
app:layout_constraintHorizontal_bias="0"
android:layout_marginStart="8dp" />
<Button
android:id="@+id/login"
android:layout_width="200dp"
android:layout_height="60dp"
android:text="Login"
app:layout_constraintTop_toBottomOf="@+id/passwordEdit"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintVertical_bias="0.1"
android:layout_marginTop="24dp"/>
</androidx.constraintlayout.widget.ConstraintLayout>
请进行优化,使得accountLabel和accountEdit的基线在同一水平位置,passwordLabel和passwordEdit的基线在同一水平位置。
为了使 accountLabel
和 accountEdit
的基线在同一水平位置,以及 passwordLabel
和 passwordEdit
的基线在同一水平位置,我们可以使用 app:layout_constraintBaseline_toBaselineOf
属性来约束它们的基线对齐。
以下是优化后的布局文件:
<?xml version="1.0" encoding="utf-8"?>
<androidx.constraintlayout.widget.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:id="@+id/loginLayout"
xmlns:app="http://schemas.android.com/apk/res-auto">
<TextView
android:id="@+id/accountLabel"
android:layout_width="0dp"
android:layout_height="wrap_content"
android:textSize="18sp"
android:text="Account:"
app:layout_constraintEnd_toStartOf="@+id/accountEdit"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="parent"
app:layout_constraintVertical_bias="0.1"
android:layout_marginEnd="8dp"
app:layout_constraintBaseline_toBaselineOf="@+id/accountEdit" />
<EditText
android:id="@+id/accountEdit"
android:layout_width="0dp"
android:layout_height="48dp"
android:layout_marginTop="16dp"
android:hint="Enter your account"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toEndOf="@+id/accountLabel"
app:layout_constraintTop_toTopOf="@+id/accountLabel"
app:layout_constraintHorizontal_bias="0"
android:layout_marginStart="8dp" />
<TextView
android:id="@+id/passwordLabel"
android:layout_width="0dp"
android:layout_height="wrap_content"
android:textSize="18sp"
android:text="Password:"
app:layout_constraintEnd_toStartOf="@+id/passwordEdit"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toBottomOf="@+id/accountEdit"
app:layout_constraintVertical_bias="0.1"
android:layout_marginEnd="8dp"
app:layout_constraintBaseline_toBaselineOf="@+id/passwordEdit" />
<EditText
android:id="@+id/passwordEdit"
android:layout_width="0dp"
android:layout_height="48dp"
android:layout_marginTop="16dp"
android:inputType="textPassword"
android:hint="Enter your password"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toEndOf="@+id/passwordLabel"
app:layout_constraintTop_toTopOf="@+id/passwordLabel"
app:layout_constraintHorizontal_bias="0"
android:layout_marginStart="8dp" />
<Button
android:id="@+id/login"
android:layout_width="200dp"
android:layout_height="60dp"
android:text="Login"
app:layout_constraintTop_toBottomOf="@+id/passwordEdit"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintVertical_bias="0.1"
android:layout_marginTop="24dp"/>
</androidx.constraintlayout.widget.ConstraintLayout>
在这个优化后的布局文件中,accountLabel
和 accountEdit
的基线通过 app:layout_constraintBaseline_toBaselineOf
属性对齐,同样地,passwordLabel
和 passwordEdit
的基线也通过该属性对齐。这样可以确保它们的基线在同一水平位置。