另一种方法是像这样更新视图的布局参数(不请求layout):

yourView.updateLayoutParams<ConstraintLayout.LayoutParams> {
        startToEnd = targetView.id
        topToTop = targetView.id
        bottomToBottom = targetView.id
        //add other constraints if needed
      }

另一种方法是像这样更新视图的布局参数(不请求layout):

yourView.updateLayoutParams<ConstraintLayout.LayoutParams> {
        startToEnd = targetView.id
        topToTop = targetView.id
        bottomToBottom = targetView.id
        //add other constraints if needed
      }

例如:

app:layout_constraintRight_toRightOf = "parentView"

如果你喜欢用程序声明它，它将是…

ConstraintLayout.LayoutParams.rightToRight = parentView.getId()

如果你使用程序来声明parentview(viewgroup)，不要忘记给parentview一个生成的id。

parentView.setId(View.generatedId());

你也可以使用TransitionManager来动画化这些变化:

public static void animateConstraintLayout(ConstraintLayout constraintLayout, ConstraintSet set, long duration) {
    AutoTransition trans = new AutoTransition();
    trans.setDuration(duration);
    trans.setInterpolator(new AccelerateDecelerateInterpolator());

    TransitionManager.beginDelayedTransition(constraintLayout, trans);
    set.applyTo(constraintLayout);
}

你可以在用ConstraintSet更新布局后这样调用它:

ConstraintSet set = new ConstraintSet();
set.clone(constraintLayout);
set.connect(R.id.example, ConstraintSet.BOTTOM, R.id.anotherExample, ConstraintSet.BOTTOM);
set.connect(R.id.example, ConstraintSet.TOP, R.id.anotherExample, ConstraintSet.TOP);

animateConstraintLayout(constraintLayout, set, 500);

假设我们想要在运行时改变约束，使button1在点击时与button2对齐:

然后，有这样的布局:

<android.support.constraint.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:id="@+id/root"
    android:paddingBottom="@dimen/activity_vertical_margin"
    android:paddingLeft="@dimen/activity_horizontal_margin"
    android:paddingRight="@dimen/activity_horizontal_margin"
    android:paddingTop="@dimen/activity_vertical_margin">


    <Button
        android:id="@+id/button1"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="Button 1"
        app:layout_constraintTop_toTopOf="@+id/button3"
        app:layout_constraintBottom_toBottomOf="@+id/button3"
        app:layout_constraintStart_toEndOf="@+id/button3"
        android:layout_marginStart="0dp"
        app:layout_constraintEnd_toEndOf="parent"
        android:layout_marginEnd="0dp" />

    <Button
        android:id="@+id/button2"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginLeft="16dp"
        android:text="Button 2"
        app:layout_constraintLeft_toLeftOf="parent"
        app:layout_constraintStart_toStartOf="parent"
        android:layout_marginStart="8dp"
        app:layout_constraintEnd_toEndOf="parent"
        android:layout_marginEnd="8dp"
        app:layout_constraintBottom_toBottomOf="parent"
        android:layout_marginBottom="8dp"
        app:layout_constraintTop_toTopOf="parent"
        android:layout_marginTop="8dp"
        app:layout_constraintHorizontal_bias="0.0"
        app:layout_constraintVertical_bias="0.5" />

    <Button
        android:id="@+id/button3"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginLeft="16dp"
        android:text="Button 3"
        app:layout_constraintLeft_toLeftOf="parent"
        app:layout_constraintStart_toStartOf="parent"
        android:layout_marginStart="8dp"
        app:layout_constraintEnd_toEndOf="parent"
        android:layout_marginEnd="8dp"
        app:layout_constraintTop_toTopOf="parent"
        android:layout_marginTop="8dp"
        app:layout_constraintBottom_toBottomOf="parent"
        android:layout_marginBottom="8dp"
        app:layout_constraintHorizontal_bias="0.0"
        app:layout_constraintVertical_bias="0.223" />
</android.support.constraint.ConstraintLayout>

我们可以做以下几点:

    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        setContentView(R.layout.activity_main)

        button1.setOnClickListener {
            val params = button1.layoutParams as ConstraintLayout.LayoutParams
            params.leftToRight = button2.id
            params.topToTop = button2.id
            params.bottomToBottom = button2.id
            button1.requestLayout()
        }
    }

To set constraints of image view to: app:layout_constraintRight_toRightOf="@+id/check_answer1" app:layout_constraintTop_toTopOf="@+id/check_answer1" use: ConstraintLayout constraintLayout = findViewById(R.id.parent_layout); ConstraintSet constraintSet = new ConstraintSet(); constraintSet.clone(constraintLayout); constraintSet.connect(R.id.imageView,ConstraintSet.RIGHT,R.id.check_answer1,ConstraintSet.RIGHT,0); constraintSet.connect(R.id.imageView,ConstraintSet.TOP,R.id.check_answer1,ConstraintSet.TOP,0); constraintSet.applyTo(constraintLayout); To set constraints of image view to: app:layout_constraintRight_toRightOf="@+id/check_answer2" app:layout_constraintTop_toTopOf="@+id/check_answer2" use: ConstraintLayout constraintLayout = findViewById(R.id.parent_layout); ConstraintSet constraintSet = new ConstraintSet(); constraintSet.clone(constraintLayout); constraintSet.connect(R.id.imageView,ConstraintSet.RIGHT,R.id.check_answer2,ConstraintSet.RIGHT,0); constraintSet.connect(R.id.imageView,ConstraintSet.TOP,R.id.check_answer2,ConstraintSet.TOP,0); constraintSet.applyTo(constraintLayout);