public class

Group

extends ConstraintHelper

 java.lang.Object

↳View

androidx.constraintlayout.widget.ConstraintHelper

↳androidx.constraintlayout.widget.Group

Gradle dependencies

compile group: 'androidx.constraintlayout', name: 'constraintlayout', version: '2.2.0-alpha01'

  • groupId: androidx.constraintlayout
  • artifactId: constraintlayout
  • version: 2.2.0-alpha01

Artifact androidx.constraintlayout:constraintlayout:2.2.0-alpha01 it located at Google repository (https://maven.google.com/)

Androidx artifact mapping:

androidx.constraintlayout:constraintlayout com.android.support.constraint:constraint-layout

Androidx class mapping:

androidx.constraintlayout.widget.Group android.support.constraint.Group

Overview

Control the visibility and elevation of the referenced views Added in 1.1

This class controls the visibility of a set of referenced widgets. Widgets are referenced by being added to a comma separated list of ids, e.g.:

     
          
     
     

The visibility of the group will be applied to the referenced widgets. It's a convenient way to easily hide/show a set of widgets without having to maintain this set programmatically.

Multiple groups

Multiple groups can reference the same widgets -- in that case, the XML declaration order will define the final visibility state (the group declared last will have the last word).

Summary

Fields
from ConstraintHelpermCount, mHelperWidget, mIds[], mMap, mReferenceIds, mReferenceTags, mUseViewMeasure, myContext
Constructors
publicGroup(Context context)

publicGroup(Context context, AttributeSet attrs)

publicGroup(Context context, AttributeSet attrs, int defStyleAttr)

Methods
protected voidapplyLayoutFeaturesInConstraintSet(ConstraintLayout container)

protected voidinit(AttributeSet attrs)

public voidonAttachedToWindow()

public voidsetElevation(float elevation)

public voidsetVisibility(int visibility)

public voidupdatePostLayout(ConstraintLayout container)

from ConstraintHelperaddView, applyLayoutFeatures, applyLayoutFeatures, containsId, getReferencedIds, getViews, indexFromId, loadParameters, onDraw, onMeasure, removeView, resolveRtl, setIds, setReferencedIds, setReferenceTags, setTag, updatePostConstraints, updatePostMeasure, updatePreDraw, updatePreLayout, updatePreLayout, validateParams
from java.lang.Objectclone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructors

public Group(Context context)

public Group(Context context, AttributeSet attrs)

public Group(Context context, AttributeSet attrs, int defStyleAttr)

Methods

protected void init(AttributeSet attrs)

Parameters:

attrs:

public void onAttachedToWindow()

public void setVisibility(int visibility)

public void setElevation(float elevation)

protected void applyLayoutFeaturesInConstraintSet(ConstraintLayout container)

Parameters:

container:

public void updatePostLayout(ConstraintLayout container)

Parameters:

container:

Source

/*
 * Copyright (C) 2021 The Android Open Source Project
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package androidx.constraintlayout.widget;

import android.content.Context;
import android.util.AttributeSet;

/**
 * Control the visibility and elevation of the referenced views
 *
 * <b>Added in 1.1</b>
 * <p>
 *     This class controls the visibility of a set of referenced widgets.
 *     Widgets are referenced by being added to a comma separated list of ids, e.g.:
 *     <pre>
 *     {@code
 *          <androidx.constraintlayout.widget.Group
 *              android:id="@+id/group"
 *              android:layout_width="wrap_content"
 *              android:layout_height="wrap_content"
 *              android:visibility="visible"
 *              app:constraint_referenced_ids="button4,button9" />
 *     }
 *     </pre>
 *     <p>
 *         The visibility of the group will be applied to the referenced widgets.
 *         It's a convenient way to easily hide/show a set of widgets
 *         without having to maintain this set
 *         programmatically.
 *     <p>
 *     <h2>Multiple groups</h2>
 *     <p>
 *         Multiple groups can reference the same widgets
 *         -- in that case, the XML declaration order will
 *         define the final visibility state (the group declared last will have the last word).
 * </p>
 */
public class Group extends ConstraintHelper {

    public Group(Context context) {
        super(context);
    }

    public Group(Context context, AttributeSet attrs) {
        super(context, attrs);
    }

    public Group(Context context, AttributeSet attrs, int defStyleAttr) {
        super(context, attrs, defStyleAttr);
    }

    /**
     * @DoNotShow
     * @param attrs
     */
    protected void init(AttributeSet attrs) {
        super.init(attrs);
        mUseViewMeasure = false;
    }

    @Override
    public void onAttachedToWindow() {
        super.onAttachedToWindow();
        applyLayoutFeatures();
    }

    @Override
    public void setVisibility(int visibility) {
        super.setVisibility(visibility);
        applyLayoutFeatures();
    }

    @Override
    public void setElevation(float elevation) {
        super.setElevation(elevation);
        applyLayoutFeatures();
    }

    /**
     * @DoNotShow
     * @param container
     */
    @Override
    protected void applyLayoutFeaturesInConstraintSet(ConstraintLayout container) {
        applyLayoutFeatures(container);
    }

    /**
     * @DoNotShow
     * @param container
     */
    @Override
    public void updatePostLayout(ConstraintLayout container) {
        ConstraintLayout.LayoutParams params = (ConstraintLayout.LayoutParams) getLayoutParams();
        params.mWidget.setWidth(0);
        params.mWidget.setHeight(0);
    }
}