ConstraintLayout：以编程方式更改约束

Question

我需要 ConstraintSet 的帮助。我的目标是在代码中更改视图的约束，但我不知道如何正确地做到这一点。

我有 4 TextView 和一个 ImageView 。我需要将 ImageView 约束设置为 TextView s之一。

 check_answer4 = (TextView) findViewById(R.id.check_answer4);
check_answer1 = (TextView) findViewById(R.id.check_answer1);
check_answer2 = (TextView) findViewById(R.id.check_answer2);
check_answer3 = (TextView) findViewById(R.id.check_answer3);

correct_answer_icon = (ImageView) findViewById(R.id.correct_answer_icon);

如果第一个答案是正确的，我需要将 ImageView 的约束设置为

app:layout_constraintRight_toRightOf="@+id/check_answer1"
app:layout_constraintTop_toTopOf="@+id/check_answer1"

如果第二个答案是正确的，我需要将 ImageView 的约束设置为

app:layout_constraintRight_toRightOf="@+id/check_answer2"
app:layout_constraintTop_toTopOf="@+id/check_answer2"

等等。

原文由 Big Coach 发布，翻译遵循 CC BY-SA 4.0 许可协议

Answer 1

1. 要将图像视图的约束设置为：

     app:layout_constraintRight_toRightOf="@+id/check_answer1"
    app:layout_constraintTop_toTopOf="@+id/check_answer1"

利用：

     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);

1. 要将图像视图的约束设置为：

     app:layout_constraintRight_toRightOf="@+id/check_answer2"
    app:layout_constraintTop_toTopOf="@+id/check_answer2"

利用：

     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);

原文由 vishakha yeolekar 发布，翻译遵循 CC BY-SA 4.0 许可协议

Answer 2

您还可以使用 TransitionManager 为更改设置动画：

 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);
}

使用 ConstraintSet 更新布局后，您可以这样调用它：

 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);

原文由 Mohamed Salah 发布，翻译遵循 CC BY-SA 4.0 许可协议