public class

ScrollingTabContainerView

extends HorizontalScrollView

 java.lang.Object

↳HorizontalScrollView

↳androidx.appcompat.widget.ScrollingTabContainerView

Gradle dependencies

compile group: 'androidx.appcompat', name: 'appcompat', version: '1.6.0-alpha04'

  • groupId: androidx.appcompat
  • artifactId: appcompat
  • version: 1.6.0-alpha04

Artifact androidx.appcompat:appcompat:1.6.0-alpha04 it located at Google repository (https://maven.google.com/)

Androidx artifact mapping:

androidx.appcompat:appcompat com.android.support:appcompat-v7

Androidx class mapping:

androidx.appcompat.widget.ScrollingTabContainerView android.support.v7.widget.ScrollingTabContainerView

Overview

This widget implements the dynamic action bar tab behavior that can change across different configurations or circumstances.

Summary

Fields
protected final ScrollingTabContainerView.VisibilityAnimListenermVisAnimListener

protected ViewPropertyAnimatormVisibilityAnim

Constructors
publicScrollingTabContainerView(Context context)

Methods
public voidaddTab(ActionBar.Tab tab, boolean setSelected)

public voidaddTab(ActionBar.Tab tab, int position, boolean setSelected)

public voidanimateToTab(int position)

public voidanimateToVisibility(int visibility)

public voidonAttachedToWindow()

protected voidonConfigurationChanged(Configuration newConfig)

public voidonDetachedFromWindow()

public voidonItemSelected(<any> adapterView, View view, int position, long id)

public voidonMeasure(int widthMeasureSpec, int heightMeasureSpec)

public voidonNothingSelected(<any> adapterView)

public voidremoveAllTabs()

public voidremoveTabAt(int position)

public voidsetAllowCollapse(boolean allowCollapse)

public voidsetContentHeight(int contentHeight)

public voidsetTabSelected(int position)

public voidupdateTab(int position)

from java.lang.Objectclone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Fields

protected ViewPropertyAnimator mVisibilityAnim

protected final ScrollingTabContainerView.VisibilityAnimListener mVisAnimListener

Constructors

public ScrollingTabContainerView(Context context)

Methods

public void onMeasure(int widthMeasureSpec, int heightMeasureSpec)

public void setAllowCollapse(boolean allowCollapse)

public void setTabSelected(int position)

public void setContentHeight(int contentHeight)

protected void onConfigurationChanged(Configuration newConfig)

public void animateToVisibility(int visibility)

public void animateToTab(int position)

public void onAttachedToWindow()

public void onDetachedFromWindow()

public void addTab(ActionBar.Tab tab, boolean setSelected)

public void addTab(ActionBar.Tab tab, int position, boolean setSelected)

public void updateTab(int position)

public void removeTabAt(int position)

public void removeAllTabs()

public void onItemSelected(<any> adapterView, View view, int position, long id)

public void onNothingSelected(<any> adapterView)

Source

/*
 * Copyright (C) 2011 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.appcompat.widget;

import static androidx.annotation.RestrictTo.Scope.LIBRARY_GROUP_PREFIX;

import android.animation.Animator;
import android.animation.AnimatorListenerAdapter;
import android.content.Context;
import android.content.res.Configuration;
import android.graphics.drawable.Drawable;
import android.text.TextUtils;
import android.text.TextUtils.TruncateAt;
import android.view.Gravity;
import android.view.View;
import android.view.ViewGroup;
import android.view.ViewParent;
import android.view.ViewPropertyAnimator;
import android.view.accessibility.AccessibilityEvent;
import android.view.accessibility.AccessibilityNodeInfo;
import android.view.animation.DecelerateInterpolator;
import android.view.animation.Interpolator;
import android.widget.AdapterView;
import android.widget.BaseAdapter;
import android.widget.HorizontalScrollView;
import android.widget.ImageView;
import android.widget.LinearLayout;
import android.widget.ListView;
import android.widget.Spinner;
import android.widget.TextView;

import androidx.annotation.NonNull;
import androidx.annotation.RestrictTo;
import androidx.appcompat.R;
import androidx.appcompat.app.ActionBar;
import androidx.appcompat.view.ActionBarPolicy;
import androidx.core.view.GravityCompat;

/**
 * This widget implements the dynamic action bar tab behavior that can change across different
 * configurations or circumstances.
 *
 * @hide
 */
@RestrictTo(LIBRARY_GROUP_PREFIX)
public class ScrollingTabContainerView extends HorizontalScrollView
        implements AdapterView.OnItemSelectedListener {

    private static final String TAG = "ScrollingTabContainerView";
    Runnable mTabSelector;
    private TabClickListener mTabClickListener;

    LinearLayoutCompat mTabLayout;
    private Spinner mTabSpinner;
    private boolean mAllowCollapse;

    int mMaxTabWidth;
    int mStackedTabMaxWidth;
    private int mContentHeight;
    private int mSelectedTabIndex;

    protected ViewPropertyAnimator mVisibilityAnim;
    protected final VisibilityAnimListener mVisAnimListener = new VisibilityAnimListener();

    private static final Interpolator sAlphaInterpolator = new DecelerateInterpolator();

    private static final int FADE_DURATION = 200;

    public ScrollingTabContainerView(@NonNull Context context) {
        super(context);

        setHorizontalScrollBarEnabled(false);

        ActionBarPolicy abp = ActionBarPolicy.get(context);
        setContentHeight(abp.getTabContainerHeight());
        mStackedTabMaxWidth = abp.getStackedTabMaxWidth();

        mTabLayout = createTabLayout();
        addView(mTabLayout, new ViewGroup.LayoutParams(ViewGroup.LayoutParams.WRAP_CONTENT,
                ViewGroup.LayoutParams.MATCH_PARENT));
    }

    @Override
    public void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
        final int widthMode = MeasureSpec.getMode(widthMeasureSpec);
        final boolean lockedExpanded = widthMode == MeasureSpec.EXACTLY;
        setFillViewport(lockedExpanded);

        final int childCount = mTabLayout.getChildCount();
        if (childCount > 1 &&
                (widthMode == MeasureSpec.EXACTLY || widthMode == MeasureSpec.AT_MOST)) {
            if (childCount > 2) {
                mMaxTabWidth = (int) (MeasureSpec.getSize(widthMeasureSpec) * 0.4f);
            } else {
                mMaxTabWidth = MeasureSpec.getSize(widthMeasureSpec) / 2;
            }
            mMaxTabWidth = Math.min(mMaxTabWidth, mStackedTabMaxWidth);
        } else {
            mMaxTabWidth = -1;
        }

        heightMeasureSpec = MeasureSpec.makeMeasureSpec(mContentHeight, MeasureSpec.EXACTLY);

        final boolean canCollapse = !lockedExpanded && mAllowCollapse;

        if (canCollapse) {
            // See if we should expand
            mTabLayout.measure(MeasureSpec.UNSPECIFIED, heightMeasureSpec);
            if (mTabLayout.getMeasuredWidth() > MeasureSpec.getSize(widthMeasureSpec)) {
                performCollapse();
            } else {
                performExpand();
            }
        } else {
            performExpand();
        }

        final int oldWidth = getMeasuredWidth();
        super.onMeasure(widthMeasureSpec, heightMeasureSpec);
        final int newWidth = getMeasuredWidth();

        if (lockedExpanded && oldWidth != newWidth) {
            // Recenter the tab display if we're at a new (scrollable) size.
            setTabSelected(mSelectedTabIndex);
        }
    }

    /**
     * Indicates whether this view is collapsed into a dropdown menu instead
     * of traditional tabs.
     * @return true if showing as a spinner
     */
    private boolean isCollapsed() {
        return mTabSpinner != null && mTabSpinner.getParent() == this;
    }

    public void setAllowCollapse(boolean allowCollapse) {
        mAllowCollapse = allowCollapse;
    }

    private void performCollapse() {
        if (isCollapsed()) return;

        if (mTabSpinner == null) {
            mTabSpinner = createSpinner();
        }
        removeView(mTabLayout);
        addView(mTabSpinner, new ViewGroup.LayoutParams(ViewGroup.LayoutParams.WRAP_CONTENT,
                ViewGroup.LayoutParams.MATCH_PARENT));
        if (mTabSpinner.getAdapter() == null) {
            mTabSpinner.setAdapter(new TabAdapter());
        }
        if (mTabSelector != null) {
            removeCallbacks(mTabSelector);
            mTabSelector = null;
        }
        mTabSpinner.setSelection(mSelectedTabIndex);
    }

    private boolean performExpand() {
        if (!isCollapsed()) return false;

        removeView(mTabSpinner);
        addView(mTabLayout, new ViewGroup.LayoutParams(ViewGroup.LayoutParams.WRAP_CONTENT,
                ViewGroup.LayoutParams.MATCH_PARENT));
        setTabSelected(mTabSpinner.getSelectedItemPosition());
        return false;
    }

    public void setTabSelected(int position) {
        mSelectedTabIndex = position;
        final int tabCount = mTabLayout.getChildCount();
        for (int i = 0; i < tabCount; i++) {
            final View child = mTabLayout.getChildAt(i);
            final boolean isSelected = i == position;
            child.setSelected(isSelected);
            if (isSelected) {
                animateToTab(position);
            }
        }
        if (mTabSpinner != null && position >= 0) {
            mTabSpinner.setSelection(position);
        }
    }

    public void setContentHeight(int contentHeight) {
        mContentHeight = contentHeight;
        requestLayout();
    }

    private LinearLayoutCompat createTabLayout() {
        final LinearLayoutCompat tabLayout = new LinearLayoutCompat(getContext(), null,
                R.attr.actionBarTabBarStyle);
        tabLayout.setMeasureWithLargestChildEnabled(true);
        tabLayout.setGravity(Gravity.CENTER);
        tabLayout.setLayoutParams(new LinearLayoutCompat.LayoutParams(
                LinearLayoutCompat.LayoutParams.WRAP_CONTENT, LinearLayoutCompat.LayoutParams.MATCH_PARENT));
        return tabLayout;
    }

    private Spinner createSpinner() {
        final Spinner spinner = new AppCompatSpinner(getContext(), null,
                R.attr.actionDropDownStyle);
        spinner.setLayoutParams(new LinearLayoutCompat.LayoutParams(
                LinearLayoutCompat.LayoutParams.WRAP_CONTENT,
                LinearLayoutCompat.LayoutParams.MATCH_PARENT));
        spinner.setOnItemSelectedListener(this);
        return spinner;
    }

    @Override
    protected void onConfigurationChanged(Configuration newConfig) {
        super.onConfigurationChanged(newConfig);

        ActionBarPolicy abp = ActionBarPolicy.get(getContext());
        // Action bar can change size on configuration changes.
        // Reread the desired height from the theme-specified style.
        setContentHeight(abp.getTabContainerHeight());
        mStackedTabMaxWidth = abp.getStackedTabMaxWidth();
    }

    public void animateToVisibility(int visibility) {
        if (mVisibilityAnim != null) {
            mVisibilityAnim.cancel();
        }
        if (visibility == VISIBLE) {
            if (getVisibility() != VISIBLE) {
                setAlpha(0f);
            }

            ViewPropertyAnimator anim = animate().alpha(1f);
            anim.setDuration(FADE_DURATION);

            anim.setInterpolator(sAlphaInterpolator);
            anim.setListener(mVisAnimListener.withFinalVisibility(anim, visibility));
            anim.start();
        } else {
            ViewPropertyAnimator anim = animate().alpha(0f);
            anim.setDuration(FADE_DURATION);

            anim.setInterpolator(sAlphaInterpolator);
            anim.setListener(mVisAnimListener.withFinalVisibility(anim, visibility));
            anim.start();
        }
    }

    public void animateToTab(final int position) {
        final View tabView = mTabLayout.getChildAt(position);
        if (mTabSelector != null) {
            removeCallbacks(mTabSelector);
        }
        mTabSelector = new Runnable() {
            @Override
            public void run() {
                final int scrollPos = tabView.getLeft() - (getWidth() - tabView.getWidth()) / 2;
                smoothScrollTo(scrollPos, 0);
                mTabSelector = null;
            }
        };
        post(mTabSelector);
    }

    @Override
    public void onAttachedToWindow() {
        super.onAttachedToWindow();
        if (mTabSelector != null) {
            // Re-post the selector we saved
            post(mTabSelector);
        }
    }

    @Override
    public void onDetachedFromWindow() {
        super.onDetachedFromWindow();
        if (mTabSelector != null) {
            removeCallbacks(mTabSelector);
        }
    }

    TabView createTabView(ActionBar.Tab tab, boolean forAdapter) {
        final TabView tabView = new TabView(getContext(), tab, forAdapter);
        if (forAdapter) {
            tabView.setBackgroundDrawable(null);
            tabView.setLayoutParams(new ListView.LayoutParams(ListView.LayoutParams.MATCH_PARENT,
                    mContentHeight));
        } else {
            tabView.setFocusable(true);

            if (mTabClickListener == null) {
                mTabClickListener = new TabClickListener();
            }
            tabView.setOnClickListener(mTabClickListener);
        }
        return tabView;
    }

    public void addTab(ActionBar.Tab tab, boolean setSelected) {
        TabView tabView = createTabView(tab, false);
        mTabLayout.addView(tabView, new LinearLayoutCompat.LayoutParams(0,
                LayoutParams.MATCH_PARENT, 1));
        if (mTabSpinner != null) {
            ((TabAdapter) mTabSpinner.getAdapter()).notifyDataSetChanged();
        }
        if (setSelected) {
            tabView.setSelected(true);
        }
        if (mAllowCollapse) {
            requestLayout();
        }
    }

    public void addTab(ActionBar.Tab tab, int position, boolean setSelected) {
        final TabView tabView = createTabView(tab, false);
        mTabLayout.addView(tabView, position, new LinearLayoutCompat.LayoutParams(
                0, LayoutParams.MATCH_PARENT, 1));
        if (mTabSpinner != null) {
            ((TabAdapter) mTabSpinner.getAdapter()).notifyDataSetChanged();
        }
        if (setSelected) {
            tabView.setSelected(true);
        }
        if (mAllowCollapse) {
            requestLayout();
        }
    }

    public void updateTab(int position) {
        ((TabView) mTabLayout.getChildAt(position)).update();
        if (mTabSpinner != null) {
            ((TabAdapter) mTabSpinner.getAdapter()).notifyDataSetChanged();
        }
        if (mAllowCollapse) {
            requestLayout();
        }
    }

    public void removeTabAt(int position) {
        mTabLayout.removeViewAt(position);
        if (mTabSpinner != null) {
            ((TabAdapter) mTabSpinner.getAdapter()).notifyDataSetChanged();
        }
        if (mAllowCollapse) {
            requestLayout();
        }
    }

    public void removeAllTabs() {
        mTabLayout.removeAllViews();
        if (mTabSpinner != null) {
            ((TabAdapter) mTabSpinner.getAdapter()).notifyDataSetChanged();
        }
        if (mAllowCollapse) {
            requestLayout();
        }
    }

    @Override
    public void onItemSelected(AdapterView<?> adapterView, View view, int position, long id) {
        TabView tabView = (TabView) view;
        tabView.getTab().select();
    }

    @Override
    public void onNothingSelected(AdapterView<?> adapterView) {
        // no-op
    }

    private class TabView extends LinearLayout {
        private final int[] BG_ATTRS = {
                android.R.attr.background
        };

        private ActionBar.Tab mTab;
        private TextView mTextView;
        private ImageView mIconView;
        private View mCustomView;

        // Class name may be obfuscated by Proguard. Hardcode the string for accessibility usage.
        private static final String ACCESSIBILITY_CLASS_NAME =
                "androidx.appcompat.app.ActionBar$Tab";

        public TabView(Context context, ActionBar.Tab tab, boolean forList) {
            super(context, null, R.attr.actionBarTabStyle);
            mTab = tab;

            TintTypedArray a = TintTypedArray.obtainStyledAttributes(context, null, BG_ATTRS,
                    R.attr.actionBarTabStyle, 0);
            if (a.hasValue(0)) {
                setBackgroundDrawable(a.getDrawable(0));
            }
            a.recycle();

            if (forList) {
                setGravity(GravityCompat.START | Gravity.CENTER_VERTICAL);
            }

            update();
        }

        public void bindTab(ActionBar.Tab tab) {
            mTab = tab;
            update();
        }

        @Override
        public void setSelected(boolean selected) {
            final boolean changed = (isSelected() != selected);
            super.setSelected(selected);
            if (changed && selected) {
                sendAccessibilityEvent(AccessibilityEvent.TYPE_VIEW_SELECTED);
            }
        }

        @Override
        public void onInitializeAccessibilityEvent(AccessibilityEvent event) {
            super.onInitializeAccessibilityEvent(event);
            // This view masquerades as an action bar tab.
            event.setClassName(ACCESSIBILITY_CLASS_NAME);
        }

        @Override
        public void onInitializeAccessibilityNodeInfo(AccessibilityNodeInfo info) {
            super.onInitializeAccessibilityNodeInfo(info);

            // This view masquerades as an action bar tab.
            info.setClassName(ACCESSIBILITY_CLASS_NAME);
        }

        @Override
        public void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
            super.onMeasure(widthMeasureSpec, heightMeasureSpec);

            // Re-measure if we went beyond our maximum size.
            if (mMaxTabWidth > 0 && getMeasuredWidth() > mMaxTabWidth) {
                super.onMeasure(MeasureSpec.makeMeasureSpec(mMaxTabWidth, MeasureSpec.EXACTLY),
                        heightMeasureSpec);
            }
        }

        public void update() {
            final ActionBar.Tab tab = mTab;
            final View custom = tab.getCustomView();
            if (custom != null) {
                final ViewParent customParent = custom.getParent();
                if (customParent != this) {
                    if (customParent != null) ((ViewGroup) customParent).removeView(custom);
                    addView(custom);
                }
                mCustomView = custom;
                if (mTextView != null) mTextView.setVisibility(GONE);
                if (mIconView != null) {
                    mIconView.setVisibility(GONE);
                    mIconView.setImageDrawable(null);
                }
            } else {
                if (mCustomView != null) {
                    removeView(mCustomView);
                    mCustomView = null;
                }

                final Drawable icon = tab.getIcon();
                final CharSequence text = tab.getText();

                if (icon != null) {
                    if (mIconView == null) {
                        ImageView iconView = new AppCompatImageView(getContext());
                        LayoutParams lp = new LayoutParams(LayoutParams.WRAP_CONTENT,
                                LayoutParams.WRAP_CONTENT);
                        lp.gravity = Gravity.CENTER_VERTICAL;
                        iconView.setLayoutParams(lp);
                        addView(iconView, 0);
                        mIconView = iconView;
                    }
                    mIconView.setImageDrawable(icon);
                    mIconView.setVisibility(VISIBLE);
                } else if (mIconView != null) {
                    mIconView.setVisibility(GONE);
                    mIconView.setImageDrawable(null);
                }

                final boolean hasText = !TextUtils.isEmpty(text);
                if (hasText) {
                    if (mTextView == null) {
                        TextView textView = new AppCompatTextView(getContext(), null,
                                R.attr.actionBarTabTextStyle);
                        textView.setEllipsize(TruncateAt.END);
                        LayoutParams lp = new LayoutParams(LayoutParams.WRAP_CONTENT,
                                LayoutParams.WRAP_CONTENT);
                        lp.gravity = Gravity.CENTER_VERTICAL;
                        textView.setLayoutParams(lp);
                        addView(textView);
                        mTextView = textView;
                    }
                    mTextView.setText(text);
                    mTextView.setVisibility(VISIBLE);
                } else if (mTextView != null) {
                    mTextView.setVisibility(GONE);
                    mTextView.setText(null);
                }

                if (mIconView != null) {
                    mIconView.setContentDescription(tab.getContentDescription());
                }
                TooltipCompat.setTooltipText(this, hasText ? null : tab.getContentDescription());
            }
        }

        public ActionBar.Tab getTab() {
            return mTab;
        }
    }

    private class TabAdapter extends BaseAdapter {
        TabAdapter() {
        }

        @Override
        public int getCount() {
            return mTabLayout.getChildCount();
        }

        @Override
        public Object getItem(int position) {
            return ((TabView) mTabLayout.getChildAt(position)).getTab();
        }

        @Override
        public long getItemId(int position) {
            return position;
        }

        @Override
        public View getView(int position, View convertView, ViewGroup parent) {
            if (convertView == null) {
                convertView = createTabView((ActionBar.Tab) getItem(position), true);
            } else {
                ((TabView) convertView).bindTab((ActionBar.Tab) getItem(position));
            }
            return convertView;
        }
    }

    private class TabClickListener implements OnClickListener {
        TabClickListener() {
        }

        @Override
        public void onClick(View view) {
            TabView tabView = (TabView) view;
            tabView.getTab().select();
            final int tabCount = mTabLayout.getChildCount();
            for (int i = 0; i < tabCount; i++) {
                final View child = mTabLayout.getChildAt(i);
                child.setSelected(child == view);
            }
        }
    }

    protected class VisibilityAnimListener extends AnimatorListenerAdapter {
        private boolean mCanceled = false;
        private int mFinalVisibility;

        public VisibilityAnimListener withFinalVisibility(ViewPropertyAnimator animation,
                int visibility) {
            mFinalVisibility = visibility;
            mVisibilityAnim = animation;
            return this;
        }

        @Override
        public void onAnimationStart(Animator animator) {
            setVisibility(VISIBLE);
            mCanceled = false;
        }

        @Override
        public void onAnimationEnd(Animator animator) {
            if (mCanceled) return;

            mVisibilityAnim = null;
            setVisibility(mFinalVisibility);
        }

        @Override
        public void onAnimationCancel(Animator animator) {
            mCanceled = true;
        }
    }
}