How can we add Views dynamically androidx.constraintlayout.helper.widget.Flow and add reference Ids

问题

How can we add Views dynamically in androidx.constraintlayout.helper.widget.Flow and add reference Ids dynamically.

回答1:

Here is Kotlin Implementation

for (i in 0..4) {
    val customView = CustomComponent (this)
    customView.id = generateViewId()
    constraintLayout.addView(customView,i)
    flow.addView(customView)
}

Following is my XML

<androidx.constraintlayout.widget.ConstraintLayout
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:id="@+id/constraintLayout"
    app:layout_constraintBottom_toBottomOf="parent"
    app:layout_constraintEnd_toEndOf="parent"
    app:layout_constraintStart_toStartOf="parent"
    >

    <androidx.constraintlayout.helper.widget.Flow
        android:id="@+id/flow"
        android:layout_width="0dp"
        android:layout_height="wrap_content"
        android:orientation="horizontal"
        app:flow_wrapMode="chain"
        app:flow_horizontalGap="2dp"
        app:flow_verticalGap="2dp"
        app:flow_verticalStyle = "spread_inside"
        app:flow_horizontalStyle="packed"
        app:layout_constraintBottom_toBottomOf="parent"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintStart_toStartOf="parent"
        />

</androidx.constraintlayout.widget.ConstraintLayout>

Following is my Custom View

class CustomComponent @JvmOverloads constructor(
context: Context,
attrs: AttributeSet? = null,
defStyle: Int = 0,
defStyleRes: Int = 0):LinearLayout(context, attrs, defStyle, defStyleRes) {
init {
    LayoutInflater.from(context)
        .inflate(R.layout.custom_view, this, true)
}}

回答2:

You should add first your view (with an id set) to the parent ConstraintLayout. Then you can add it's reference id to your Flow with Flow.addView(). For example:

val view = LayoutInflater.from(context).inflate(R.layout.item, this, false)
view.layoutParams = ConstraintLayout.LayoutParams(WRAP_CONTENT, WRAP_CONTENT)
view.id = View.generateViewId()
constraintLayout.addView(view)
flow.addView(view)

with this xml as your ViewGroup:

<?xml version="1.0" encoding="utf-8"?>
<androidx.constraintlayout.widget.ConstraintLayout
    xmlns:android="http://schemas.android.com/apk/res/android"
    android:id="@+id/constraintLayout"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    >

  <androidx.constraintlayout.helper.widget.Flow
      android:id="@+id/flow"
      android:layout_width="0dp"
      android:layout_height="wrap_content"
      android:orientation="horizontal"
      app:flow_wrapMode="chain"
      app:layout_constraintBottom_toBottomOf="parent"
      app:layout_constraintEnd_toEndOf="parent"
      app:layout_constraintStart_toStartOf="parent"
      />
</androidx.constraintlayout.widget.ConstraintLayout>

回答3:

view1.setId(View.generateViewId());
view2.setId(View.generateViewId());
view3.setId(View.generateViewId());
flow.setReferencedIds(new int[]{view1.getId(), view2.getId(), view3.getId()});

回答4:

You can give ID to your constraint layout and after that in .class file you can initialize that layout.

After initializing the layout you can add Views.

For example you want TextView dynamically.

TextView[] tv = new TextView[SIZE];
  for (int i=0;i<myList.size();i++){
   tv[i] = new TextView(this);
   tv[i].setLayoutParams(LAYOUT_PARAMS);
   CONSTRAINT_LAYOUT_ID.addView(tv[i]);
 }

来源：https://stackoverflow.com/questions/59084494/how-can-we-add-views-dynamically-androidx-constraintlayout-helper-widget-flow-an

标签

android

constraints

android-constraintlayout