Population of the tabs to display is * done through {@link Tab} instances. You create tabs via {@link #newTab()}. From there you can * change the tab's label or icon via {@link Tab#setText(int)} and {@link Tab#setIcon(int)} * respectively. To display the tab, you need to add it to the layout via one of the * {@link #addTab(Tab)} methods. For example: *
* TabLayout tabLayout = ...;
* tabLayout.addTab(tabLayout.newTab().setText("Tab 1"));
* tabLayout.addTab(tabLayout.newTab().setText("Tab 2"));
* tabLayout.addTab(tabLayout.newTab().setText("Tab 3"));
*
* You should set a listener via {@link #setOnTabSelectedListener(OnTabSelectedListener)} to be
* notified when any tab's selection state has been changed.
*
* You can also add items to TabLayout in your layout through the use of {@link TabItem}. * An example usage is like so:
* ** <android.support.design.widget.TabLayout * android:layout_height="wrap_content" * android:layout_width="match_parent"> * * <android.support.design.widget.TabItem * android:text="@string/tab_text"/> * * <android.support.design.widget.TabItem * android:icon="@drawable/ic_android"/> * * </android.support.design.widget.TabLayout> ** *
* If you're using a {@link android.support.v4.view.ViewPager} together * with this layout, you can call {@link #setupWithViewPager(ViewPager)} to link the two together. * This layout will be automatically populated from the {@link PagerAdapter}'s page titles.
* ** This view also supports being used as part of a ViewPager's decor, and can be added * directly to the ViewPager in a layout resource file like so:
* ** <android.support.v4.view.ViewPager * android:layout_width="match_parent" * android:layout_height="match_parent"> * * <android.support.design.widget.TabLayout * android:layout_width="match_parent" * android:layout_height="wrap_content" * android:layout_gravity="top" /> * * </android.support.v4.view.ViewPager> ** * @see Tabs * * @attr ref android.support.design.R.styleable#TabLayout_tabPadding * @attr ref android.support.design.R.styleable#TabLayout_tabPaddingStart * @attr ref android.support.design.R.styleable#TabLayout_tabPaddingTop * @attr ref android.support.design.R.styleable#TabLayout_tabPaddingEnd * @attr ref android.support.design.R.styleable#TabLayout_tabPaddingBottom * @attr ref android.support.design.R.styleable#TabLayout_tabContentStart * @attr ref android.support.design.R.styleable#TabLayout_tabBackground * @attr ref android.support.design.R.styleable#TabLayout_tabMinWidth * @attr ref android.support.design.R.styleable#TabLayout_tabMaxWidth * @attr ref android.support.design.R.styleable#TabLayout_tabTextAppearance */ @ViewPager.DecorView public class TabLayout extends HorizontalScrollView { private static final int DEFAULT_HEIGHT_WITH_TEXT_ICON = 72; // dps private static final int DEFAULT_GAP_TEXT_ICON = 8; // dps private static final int INVALID_WIDTH = -1; private static final int DEFAULT_HEIGHT = 48; // dps private static final int TAB_MIN_WIDTH_MARGIN = 56; //dps private static final int FIXED_WRAP_GUTTER_MIN = 16; //dps private static final int MOTION_NON_ADJACENT_OFFSET = 24; private static final int ANIMATION_DURATION = 300; private static final Pools.Pool
* Calling this method does not update the selected tab, it is only used for drawing purposes.
*
* @param position current scroll position
* @param positionOffset Value from [0, 1) indicating the offset from {@code position}.
* @param updateSelectedText Whether to update the text's selected state.
*/
public void setScrollPosition(int position, float positionOffset, boolean updateSelectedText) {
setScrollPosition(position, positionOffset, updateSelectedText, true);
}
private void setScrollPosition(int position, float positionOffset, boolean updateSelectedText,
boolean updateIndicatorPosition) {
final int roundedPosition = Math.round(position + positionOffset);
if (roundedPosition < 0 || roundedPosition >= mTabStrip.getChildCount()) {
return;
}
// Set the indicator position, if enabled
if (updateIndicatorPosition) {
mTabStrip.setIndicatorPositionFromTabPosition(position, positionOffset);
}
// Now update the scroll position, canceling any running animation
if (mScrollAnimator != null && mScrollAnimator.isRunning()) {
mScrollAnimator.cancel();
}
scrollTo(calculateScrollXForTab(position, positionOffset), 0);
// Update the 'selected state' view as we scroll, if enabled
if (updateSelectedText) {
setSelectedTabView(roundedPosition);
}
}
private float getScrollPosition() {
return mTabStrip.getIndicatorPosition();
}
/**
* Add a tab to this layout. The tab will be added at the end of the list.
* If this is the first tab to be added it will become the selected tab.
*
* @param tab Tab to add
*/
public void addTab(@NonNull Tab tab) {
addTab(tab, mTabs.isEmpty());
}
/**
* Add a tab to this layout. The tab will be inserted at position.
* If this is the first tab to be added it will become the selected tab.
*
* @param tab The tab to add
* @param position The new position of the tab
*/
public void addTab(@NonNull Tab tab, int position) {
addTab(tab, position, mTabs.isEmpty());
}
/**
* Add a tab to this layout. The tab will be added at the end of the list.
*
* @param tab Tab to add
* @param setSelected True if the added tab should become the selected tab.
*/
public void addTab(@NonNull Tab tab, boolean setSelected) {
addTab(tab, mTabs.size(), setSelected);
}
/**
* Add a tab to this layout. The tab will be inserted at position.
*
* @param tab The tab to add
* @param position The new position of the tab
* @param setSelected True if the added tab should become the selected tab.
*/
public void addTab(@NonNull Tab tab, int position, boolean setSelected) {
if (tab.mParent != this) {
throw new IllegalArgumentException("Tab belongs to a different TabLayout.");
}
configureTab(tab, position);
addTabView(tab);
if (setSelected) {
tab.select();
}
}
private void addTabFromItemView(@NonNull TabItem item) {
final Tab tab = newTab();
if (item.mText != null) {
tab.setText(item.mText);
}
if (item.mIcon != null) {
tab.setIcon(item.mIcon);
}
if (item.mCustomLayout != 0) {
tab.setCustomView(item.mCustomLayout);
}
if (!TextUtils.isEmpty(item.getContentDescription())) {
tab.setContentDescription(item.getContentDescription());
}
addTab(tab);
}
/**
* @deprecated Use {@link #addOnTabSelectedListener(OnTabSelectedListener)} and
* {@link #removeOnTabSelectedListener(OnTabSelectedListener)}.
*/
@Deprecated
public void setOnTabSelectedListener(@Nullable OnTabSelectedListener listener) {
// The logic in this method emulates what we had before support for multiple
// registered listeners.
if (mSelectedListener != null) {
removeOnTabSelectedListener(mSelectedListener);
}
// Update the deprecated field so that we can remove the passed listener the next
// time we're called
mSelectedListener = listener;
if (listener != null) {
addOnTabSelectedListener(listener);
}
}
/**
* Add a {@link TabLayout.OnTabSelectedListener} that will be invoked when tab selection
* changes.
*
*
Components that add a listener should take care to remove it when finished via * {@link #removeOnTabSelectedListener(OnTabSelectedListener)}.
* * @param listener listener to add */ public void addOnTabSelectedListener(@NonNull OnTabSelectedListener listener) { if (!mSelectedListeners.contains(listener)) { mSelectedListeners.add(listener); } } /** * Remove the given {@link TabLayout.OnTabSelectedListener} that was previously added via * {@link #addOnTabSelectedListener(OnTabSelectedListener)}. * * @param listener listener to remove */ public void removeOnTabSelectedListener(@NonNull OnTabSelectedListener listener) { mSelectedListeners.remove(listener); } /** * Create and return a new {@link Tab}. You need to manually add this using * {@link #addTab(Tab)} or a related method. * * @return A new Tab * @see #addTab(Tab) */ @NonNull public Tab newTab() { Tab tab = sTabPool.acquire(); if (tab == null) { tab = new Tab(); } tab.mParent = this; tab.mView = createTabView(tab); return tab; } /** * Returns the number of tabs currently registered with the action bar. * * @return Tab count */ public int getTabCount() { return mTabs.size(); } /** * Returns the tab at the specified index. */ @Nullable public Tab getTabAt(int index) { return mTabs.get(index); } /** * Returns the position of the current selected tab. * * @return selected tab position, or {@code -1} if there isn't a selected tab. */ public int getSelectedTabPosition() { return mSelectedTab != null ? mSelectedTab.getPosition() : -1; } /** * Remove a tab from the layout. If the removed tab was selected it will be deselected * and another tab will be selected if present. * * @param tab The tab to remove */ public void removeTab(Tab tab) { if (tab.mParent != this) { throw new IllegalArgumentException("Tab does not belong to this TabLayout."); } removeTabAt(tab.getPosition()); } /** * Remove a tab from the layout. If the removed tab was selected it will be deselected * and another tab will be selected if present. * * @param position Position of the tab to remove */ public void removeTabAt(int position) { final int selectedTabPosition = mSelectedTab != null ? mSelectedTab.getPosition() : 0; removeTabViewAt(position); final Tab removedTab = mTabs.remove(position); if (removedTab != null) { removedTab.reset(); sTabPool.release(removedTab); } final int newTabCount = mTabs.size(); for (int i = position; i < newTabCount; i++) { mTabs.get(i).setPosition(i); } if (selectedTabPosition == position) { selectTab(mTabs.isEmpty() ? null : mTabs.get(Math.max(0, position - 1))); } } /** * Remove all tabs from the action bar and deselect the current tab. */ public void removeAllTabs() { // Remove all the views for (int i = mTabStrip.getChildCount() - 1; i >= 0; i--) { removeTabViewAt(i); } for (final IteratorThis is the same as calling {@link #setupWithViewPager(ViewPager, boolean)} with * auto-refresh enabled.
* * @param viewPager the ViewPager to link to, or {@code null} to clear any previous link */ public void setupWithViewPager(@Nullable ViewPager viewPager) { setupWithViewPager(viewPager, true); } /** * The one-stop shop for setting up this {@link TabLayout} with a {@link ViewPager}. * *This method will link the given ViewPager and this TabLayout together so that * changes in one are automatically reflected in the other. This includes scroll state changes * and clicks. The tabs displayed in this layout will be populated * from the ViewPager adapter's page titles.
* *If {@code autoRefresh} is {@code true}, any changes in the {@link PagerAdapter} will * trigger this layout to re-populate itself from the adapter's titles.
* *If the given ViewPager is non-null, it needs to already have a * {@link PagerAdapter} set.
* * @param viewPager the ViewPager to link to, or {@code null} to clear any previous link * @param autoRefresh whether this layout should refresh its contents if the given ViewPager's * content changes */ public void setupWithViewPager(@Nullable final ViewPager viewPager, boolean autoRefresh) { setupWithViewPager(viewPager, autoRefresh, false); } private void setupWithViewPager(@Nullable final ViewPager viewPager, boolean autoRefresh, boolean implicitSetup) { if (mViewPager != null) { // If we've already been setup with a ViewPager, remove us from it if (mPageChangeListener != null) { mViewPager.removeOnPageChangeListener(mPageChangeListener); } if (mAdapterChangeListener != null) { mViewPager.removeOnAdapterChangeListener(mAdapterChangeListener); } } if (mCurrentVpSelectedListener != null) { // If we already have a tab selected listener for the ViewPager, remove it removeOnTabSelectedListener(mCurrentVpSelectedListener); mCurrentVpSelectedListener = null; } if (viewPager != null) { mViewPager = viewPager; // Add our custom OnPageChangeListener to the ViewPager if (mPageChangeListener == null) { mPageChangeListener = new TabLayoutOnPageChangeListener(this); } mPageChangeListener.reset(); viewPager.addOnPageChangeListener(mPageChangeListener); // Now we'll add a tab selected listener to set ViewPager's current item mCurrentVpSelectedListener = new ViewPagerOnTabSelectedListener(viewPager); addOnTabSelectedListener(mCurrentVpSelectedListener); final PagerAdapter adapter = viewPager.getAdapter(); if (adapter != null) { // Now we'll populate ourselves from the pager adapter, adding an observer if // autoRefresh is enabled setPagerAdapter(adapter, autoRefresh); } // Add a listener so that we're notified of any adapter changes if (mAdapterChangeListener == null) { mAdapterChangeListener = new AdapterChangeListener(); } mAdapterChangeListener.setAutoRefresh(autoRefresh); viewPager.addOnAdapterChangeListener(mAdapterChangeListener); // Now update the scroll position to match the ViewPager's current item setScrollPosition(viewPager.getCurrentItem(), 0f, true); } else { // We've been given a null ViewPager so we need to clear out the internal state, // listeners and observers mViewPager = null; setPagerAdapter(null, false); } mSetupViewPagerImplicitly = implicitSetup; } /** * @deprecated Use {@link #setupWithViewPager(ViewPager)} to link a TabLayout with a ViewPager * together. When that method is used, the TabLayout will be automatically updated * when the {@link PagerAdapter} is changed. */ @Deprecated public void setTabsFromPagerAdapter(@Nullable final PagerAdapter adapter) { setPagerAdapter(adapter, false); } @Override public boolean shouldDelayChildPressedState() { // Only delay the pressed state if the tabs can scroll return getTabScrollRange() > 0; } @Override protected void onAttachedToWindow() { super.onAttachedToWindow(); if (mViewPager == null) { // If we don't have a ViewPager already, check if our parent is a ViewPager to // setup with it automatically final ViewParent vp = getParent(); if (vp instanceof ViewPager) { // If we have a ViewPager parent and we've been added as part of its decor, let's // assume that we should automatically setup to display any titles setupWithViewPager((ViewPager) vp, true, true); } } } @Override protected void onDetachedFromWindow() { super.onDetachedFromWindow(); if (mSetupViewPagerImplicitly) { // If we've been setup with a ViewPager implicitly, let's clear out any listeners, etc setupWithViewPager(null); mSetupViewPagerImplicitly = false; } } private int getTabScrollRange() { return Math.max(0, mTabStrip.getWidth() - getWidth() - getPaddingLeft() - getPaddingRight()); } private void setPagerAdapter(@Nullable final PagerAdapter adapter, final boolean addObserver) { if (mPagerAdapter != null && mPagerAdapterObserver != null) { // If we already have a PagerAdapter, unregister our observer mPagerAdapter.unregisterDataSetObserver(mPagerAdapterObserver); } mPagerAdapter = adapter; if (addObserver && adapter != null) { // Register our observer on the new adapter if (mPagerAdapterObserver == null) { mPagerAdapterObserver = new PagerAdapterObserver(); } adapter.registerDataSetObserver(mPagerAdapterObserver); } // Finally make sure we reflect the new adapter populateFromPagerAdapter(); } private void populateFromPagerAdapter() { removeAllTabs(); if (mPagerAdapter != null) { final int adapterCount = mPagerAdapter.getCount(); for (int i = 0; i < adapterCount; i++) { addTab(newTab().setText(mPagerAdapter.getPageTitle(i)), false); } // Make sure we reflect the currently set ViewPager item if (mViewPager != null && adapterCount > 0) { final int curItem = mViewPager.getCurrentItem(); if (curItem != getSelectedTabPosition() && curItem < getTabCount()) { selectTab(getTabAt(curItem)); } } } } private void updateAllTabs() { for (int i = 0, z = mTabs.size(); i < z; i++) { mTabs.get(i).updateView(); } } private TabView createTabView(@NonNull final Tab tab) { TabView tabView = mTabViewPool != null ? mTabViewPool.acquire() : null; if (tabView == null) { tabView = new TabView(getContext()); } tabView.setTab(tab); tabView.setFocusable(true); tabView.setMinimumWidth(getTabMinWidth()); return tabView; } private void configureTab(Tab tab, int position) { tab.setPosition(position); mTabs.add(position, tab); final int count = mTabs.size(); for (int i = position + 1; i < count; i++) { mTabs.get(i).setPosition(i); } } private void addTabView(Tab tab) { final TabView tabView = tab.mView; mTabStrip.addView(tabView, tab.getPosition(), createLayoutParamsForTabs()); } @Override public void addView(View child) { addViewInternal(child); } @Override public void addView(View child, int index) { addViewInternal(child); } @Override public void addView(View child, ViewGroup.LayoutParams params) { addViewInternal(child); } @Override public void addView(View child, int index, ViewGroup.LayoutParams params) { addViewInternal(child); } private void addViewInternal(final View child) { if (child instanceof TabItem) { addTabFromItemView((TabItem) child); } else { throw new IllegalArgumentException("Only TabItem instances can be added to TabLayout"); } } private LinearLayout.LayoutParams createLayoutParamsForTabs() { final LinearLayout.LayoutParams lp = new LinearLayout.LayoutParams( LayoutParams.WRAP_CONTENT, LayoutParams.MATCH_PARENT); updateTabViewLayoutParams(lp); return lp; } private void updateTabViewLayoutParams(LinearLayout.LayoutParams lp) { if (mMode == MODE_FIXED && mTabGravity == GRAVITY_FILL) { lp.width = 0; lp.weight = 1; } else { lp.width = LinearLayout.LayoutParams.WRAP_CONTENT; lp.weight = 0; } } private int dpToPx(int dps) { return Math.round(getResources().getDisplayMetrics().density * dps); } @Override protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) { // If we have a MeasureSpec which allows us to decide our height, try and use the default // height final int idealHeight = dpToPx(getDefaultHeight()) + getPaddingTop() + getPaddingBottom(); switch (MeasureSpec.getMode(heightMeasureSpec)) { case MeasureSpec.AT_MOST: heightMeasureSpec = MeasureSpec.makeMeasureSpec( Math.min(idealHeight, MeasureSpec.getSize(heightMeasureSpec)), MeasureSpec.EXACTLY); break; case MeasureSpec.UNSPECIFIED: heightMeasureSpec = MeasureSpec.makeMeasureSpec(idealHeight, MeasureSpec.EXACTLY); break; } final int specWidth = MeasureSpec.getSize(widthMeasureSpec); if (MeasureSpec.getMode(widthMeasureSpec) != MeasureSpec.UNSPECIFIED) { // If we don't have an unspecified width spec, use the given size to calculate // the max tab width mTabMaxWidth = mRequestedTabMaxWidth > 0 ? mRequestedTabMaxWidth : specWidth - dpToPx(TAB_MIN_WIDTH_MARGIN); } // Now super measure itself using the (possibly) modified height spec super.onMeasure(widthMeasureSpec, heightMeasureSpec); if (getChildCount() == 1) { // If we're in fixed mode then we need to make the tab strip is the same width as us // so we don't scroll final View child = getChildAt(0); boolean remeasure = false; switch (mMode) { case MODE_SCROLLABLE: // We only need to resize the child if it's smaller than us. This is similar // to fillViewport remeasure = child.getMeasuredWidth() < getMeasuredWidth(); break; case MODE_FIXED: // Resize the child so that it doesn't scroll remeasure = child.getMeasuredWidth() != getMeasuredWidth(); break; } if (remeasure) { // Re-measure the child with a widthSpec set to be exactly our measure width int childHeightMeasureSpec = getChildMeasureSpec(heightMeasureSpec, getPaddingTop() + getPaddingBottom(), child.getLayoutParams().height); int childWidthMeasureSpec = MeasureSpec.makeMeasureSpec( getMeasuredWidth(), MeasureSpec.EXACTLY); child.measure(childWidthMeasureSpec, childHeightMeasureSpec); } } } private void removeTabViewAt(int position) { final TabView view = (TabView) mTabStrip.getChildAt(position); mTabStrip.removeViewAt(position); if (view != null) { view.reset(); mTabViewPool.release(view); } requestLayout(); } private void animateToTab(int newPosition) { if (newPosition == Tab.INVALID_POSITION) { return; } if (getWindowToken() == null || !ViewCompat.isLaidOut(this) || mTabStrip.childrenNeedLayout()) { // If we don't have a window token, or we haven't been laid out yet just draw the new // position now setScrollPosition(newPosition, 0f, true); return; } final int startScrollX = getScrollX(); final int targetScrollX = calculateScrollXForTab(newPosition, 0); if (startScrollX != targetScrollX) { if (mScrollAnimator == null) { mScrollAnimator = ViewUtils.createAnimator(); mScrollAnimator.setInterpolator(AnimationUtils.FAST_OUT_SLOW_IN_INTERPOLATOR); mScrollAnimator.setDuration(ANIMATION_DURATION); mScrollAnimator.setUpdateListener(new ValueAnimatorCompat.AnimatorUpdateListener() { @Override public void onAnimationUpdate(ValueAnimatorCompat animator) { scrollTo(animator.getAnimatedIntValue(), 0); } }); } mScrollAnimator.setIntValues(startScrollX, targetScrollX); mScrollAnimator.start(); } // Now animate the indicator mTabStrip.animateIndicatorToPosition(newPosition, ANIMATION_DURATION); } private void setSelectedTabView(int position) { final int tabCount = mTabStrip.getChildCount(); if (position < tabCount) { for (int i = 0; i < tabCount; i++) { final View child = mTabStrip.getChildAt(i); child.setSelected(i == position); } } } void selectTab(Tab tab) { selectTab(tab, true); } void selectTab(final Tab tab, boolean updateIndicator) { final Tab currentTab = mSelectedTab; if (currentTab == tab) { if (currentTab != null) { dispatchTabReselected(tab); animateToTab(tab.getPosition()); } } else { final int newPosition = tab != null ? tab.getPosition() : Tab.INVALID_POSITION; if (updateIndicator) { if ((currentTab == null || currentTab.getPosition() == Tab.INVALID_POSITION) && newPosition != Tab.INVALID_POSITION) { // If we don't currently have a tab, just draw the indicator setScrollPosition(newPosition, 0f, true); } else { animateToTab(newPosition); } } if (newPosition != Tab.INVALID_POSITION) { setSelectedTabView(newPosition); } dispatchTabUnselected(currentTab); mSelectedTab = tab; dispatchTabSelected(tab); } } private void dispatchTabSelected(@NonNull final Tab tab) { for (int i = mSelectedListeners.size() - 1; i >= 0; i--) { mSelectedListeners.get(i).onTabSelected(tab); } } private void dispatchTabUnselected(@NonNull final Tab tab) { for (int i = mSelectedListeners.size() - 1; i >= 0; i--) { mSelectedListeners.get(i).onTabUnselected(tab); } } private void dispatchTabReselected(@NonNull final Tab tab) { for (int i = mSelectedListeners.size() - 1; i >= 0; i--) { mSelectedListeners.get(i).onTabReselected(tab); } } private int calculateScrollXForTab(int position, float positionOffset) { if (mMode == MODE_SCROLLABLE) { final View selectedChild = mTabStrip.getChildAt(position); final View nextChild = position + 1 < mTabStrip.getChildCount() ? mTabStrip.getChildAt(position + 1) : null; final int selectedWidth = selectedChild != null ? selectedChild.getWidth() : 0; final int nextWidth = nextChild != null ? nextChild.getWidth() : 0; return selectedChild.getLeft() + ((int) ((selectedWidth + nextWidth) * positionOffset * 0.5f)) + (selectedChild.getWidth() / 2) - (getWidth() / 2); } return 0; } private void applyModeAndGravity() { int paddingStart = 0; if (mMode == MODE_SCROLLABLE) { // If we're scrollable, or fixed at start, inset using padding paddingStart = Math.max(0, mContentInsetStart - mTabPaddingStart); } ViewCompat.setPaddingRelative(mTabStrip, paddingStart, 0, 0, 0); switch (mMode) { case MODE_FIXED: mTabStrip.setGravity(Gravity.CENTER_HORIZONTAL); break; case MODE_SCROLLABLE: mTabStrip.setGravity(GravityCompat.START); break; } updateTabViews(true); } private void updateTabViews(final boolean requestLayout) { for (int i = 0; i < mTabStrip.getChildCount(); i++) { View child = mTabStrip.getChildAt(i); child.setMinimumWidth(getTabMinWidth()); updateTabViewLayoutParams((LinearLayout.LayoutParams) child.getLayoutParams()); if (requestLayout) { child.requestLayout(); } } } /** * A tab in this layout. Instances can be created via {@link #newTab()}. */ public static final class Tab { /** * An invalid position for a tab. * * @see #getPosition() */ public static final int INVALID_POSITION = -1; private Object mTag; private Drawable mIcon; private CharSequence mText; private CharSequence mContentDesc; private int mPosition = INVALID_POSITION; private View mCustomView; private TabLayout mParent; private TabView mView; private Tab() { // Private constructor } /** * @return This Tab's tag object. */ @Nullable public Object getTag() { return mTag; } /** * Give this Tab an arbitrary object to hold for later use. * * @param tag Object to store * @return The current instance for call chaining */ @NonNull public Tab setTag(@Nullable Object tag) { mTag = tag; return this; } /** * Returns the custom view used for this tab. * * @see #setCustomView(View) * @see #setCustomView(int) */ @Nullable public View getCustomView() { return mCustomView; } /** * Set a custom view to be used for this tab. ** If the provided view contains a {@link TextView} with an ID of * {@link android.R.id#text1} then that will be updated with the value given * to {@link #setText(CharSequence)}. Similarly, if this layout contains an * {@link ImageView} with ID {@link android.R.id#icon} then it will be updated with * the value given to {@link #setIcon(Drawable)}. *
* * @param view Custom view to be used as a tab. * @return The current instance for call chaining */ @NonNull public Tab setCustomView(@Nullable View view) { mCustomView = view; updateView(); return this; } /** * Set a custom view to be used for this tab. ** If the inflated layout contains a {@link TextView} with an ID of * {@link android.R.id#text1} then that will be updated with the value given * to {@link #setText(CharSequence)}. Similarly, if this layout contains an * {@link ImageView} with ID {@link android.R.id#icon} then it will be updated with * the value given to {@link #setIcon(Drawable)}. *
* * @param resId A layout resource to inflate and use as a custom tab view * @return The current instance for call chaining */ @NonNull public Tab setCustomView(@LayoutRes int resId) { final LayoutInflater inflater = LayoutInflater.from(mView.getContext()); return setCustomView(inflater.inflate(resId, mView, false)); } /** * Return the icon associated with this tab. * * @return The tab's icon */ @Nullable public Drawable getIcon() { return mIcon; } /** * Return the current position of this tab in the action bar. * * @return Current position, or {@link #INVALID_POSITION} if this tab is not currently in * the action bar. */ public int getPosition() { return mPosition; } void setPosition(int position) { mPosition = position; } /** * Return the text of this tab. * * @return The tab's text */ @Nullable public CharSequence getText() { return mText; } /** * Set the icon displayed on this tab. * * @param icon The drawable to use as an icon * @return The current instance for call chaining */ @NonNull public Tab setIcon(@Nullable Drawable icon) { mIcon = icon; updateView(); return this; } /** * Set the icon displayed on this tab. * * @param resId A resource ID referring to the icon that should be displayed * @return The current instance for call chaining */ @NonNull public Tab setIcon(@DrawableRes int resId) { if (mParent == null) { throw new IllegalArgumentException("Tab not attached to a TabLayout"); } return setIcon(AppCompatDrawableManager.get().getDrawable(mParent.getContext(), resId)); } /** * Set the text displayed on this tab. Text may be truncated if there is not room to display * the entire string. * * @param text The text to display * @return The current instance for call chaining */ @NonNull public Tab setText(@Nullable CharSequence text) { mText = text; updateView(); return this; } /** * Set the text displayed on this tab. Text may be truncated if there is not room to display * the entire string. * * @param resId A resource ID referring to the text that should be displayed * @return The current instance for call chaining */ @NonNull public Tab setText(@StringRes int resId) { if (mParent == null) { throw new IllegalArgumentException("Tab not attached to a TabLayout"); } return setText(mParent.getResources().getText(resId)); } /** * Select this tab. Only valid if the tab has been added to the action bar. */ public void select() { if (mParent == null) { throw new IllegalArgumentException("Tab not attached to a TabLayout"); } mParent.selectTab(this); } /** * Returns true if this tab is currently selected. */ public boolean isSelected() { if (mParent == null) { throw new IllegalArgumentException("Tab not attached to a TabLayout"); } return mParent.getSelectedTabPosition() == mPosition; } /** * Set a description of this tab's content for use in accessibility support. If no content * description is provided the title will be used. * * @param resId A resource ID referring to the description text * @return The current instance for call chaining * @see #setContentDescription(CharSequence) * @see #getContentDescription() */ @NonNull public Tab setContentDescription(@StringRes int resId) { if (mParent == null) { throw new IllegalArgumentException("Tab not attached to a TabLayout"); } return setContentDescription(mParent.getResources().getText(resId)); } /** * Set a description of this tab's content for use in accessibility support. If no content * description is provided the title will be used. * * @param contentDesc Description of this tab's content * @return The current instance for call chaining * @see #setContentDescription(int) * @see #getContentDescription() */ @NonNull public Tab setContentDescription(@Nullable CharSequence contentDesc) { mContentDesc = contentDesc; updateView(); return this; } /** * Gets a brief description of this tab's content for use in accessibility support. * * @return Description of this tab's content * @see #setContentDescription(CharSequence) * @see #setContentDescription(int) */ @Nullable public CharSequence getContentDescription() { return mContentDesc; } private void updateView() { if (mView != null) { mView.update(); } } private void reset() { mParent = null; mView = null; mTag = null; mIcon = null; mText = null; mContentDesc = null; mPosition = INVALID_POSITION; mCustomView = null; } } class TabView extends LinearLayout implements OnLongClickListener { private Tab mTab; private TextView mTextView; private ImageView mIconView; private View mCustomView; private TextView mCustomTextView; private ImageView mCustomIconView; private int mDefaultMaxLines = 2; public TabView(Context context) { super(context); if (mTabBackgroundResId != 0) { setBackgroundDrawable( AppCompatDrawableManager.get().getDrawable(context, mTabBackgroundResId)); } ViewCompat.setPaddingRelative(this, mTabPaddingStart, mTabPaddingTop, mTabPaddingEnd, mTabPaddingBottom); setGravity(Gravity.CENTER); setOrientation(VERTICAL); setClickable(true); } @Override public boolean performClick() { final boolean value = super.performClick(); if (mTab != null) { mTab.select(); return true; } else { return value; } } @Override public void setSelected(final boolean selected) { final boolean changed = isSelected() != selected; super.setSelected(selected); if (changed && selected && Build.VERSION.SDK_INT < 16) { // Pre-JB we need to manually send the TYPE_VIEW_SELECTED event sendAccessibilityEvent(AccessibilityEvent.TYPE_VIEW_SELECTED); } // Always dispatch this to the child views, regardless of whether the value has // changed if (mTextView != null) { mTextView.setSelected(selected); } if (mIconView != null) { mIconView.setSelected(selected); } if (mCustomView != null) { mCustomView.setSelected(selected); } } @TargetApi(Build.VERSION_CODES.ICE_CREAM_SANDWICH) @Override public void onInitializeAccessibilityEvent(AccessibilityEvent event) { super.onInitializeAccessibilityEvent(event); // This view masquerades as an action bar tab. event.setClassName(ActionBar.Tab.class.getName()); } @TargetApi(Build.VERSION_CODES.ICE_CREAM_SANDWICH) @Override public void onInitializeAccessibilityNodeInfo(AccessibilityNodeInfo info) { super.onInitializeAccessibilityNodeInfo(info); // This view masquerades as an action bar tab. info.setClassName(ActionBar.Tab.class.getName()); } @Override public void onMeasure(final int origWidthMeasureSpec, final int origHeightMeasureSpec) { final int specWidthSize = MeasureSpec.getSize(origWidthMeasureSpec); final int specWidthMode = MeasureSpec.getMode(origWidthMeasureSpec); final int maxWidth = getTabMaxWidth(); final int widthMeasureSpec; final int heightMeasureSpec = origHeightMeasureSpec; if (maxWidth > 0 && (specWidthMode == MeasureSpec.UNSPECIFIED || specWidthSize > maxWidth)) { // If we have a max width and a given spec which is either unspecified or // larger than the max width, update the width spec using the same mode widthMeasureSpec = MeasureSpec.makeMeasureSpec(mTabMaxWidth, MeasureSpec.AT_MOST); } else { // Else, use the original width spec widthMeasureSpec = origWidthMeasureSpec; } // Now lets measure super.onMeasure(widthMeasureSpec, heightMeasureSpec); // We need to switch the text size based on whether the text is spanning 2 lines or not if (mTextView != null) { final Resources res = getResources(); float textSize = mTabTextSize; int maxLines = mDefaultMaxLines; if (mIconView != null && mIconView.getVisibility() == VISIBLE) { // If the icon view is being displayed, we limit the text to 1 line maxLines = 1; } else if (mTextView != null && mTextView.getLineCount() > 1) { // Otherwise when we have text which wraps we reduce the text size textSize = mTabTextMultiLineSize; } final float curTextSize = mTextView.getTextSize(); final int curLineCount = mTextView.getLineCount(); final int curMaxLines = TextViewCompat.getMaxLines(mTextView); if (textSize != curTextSize || (curMaxLines >= 0 && maxLines != curMaxLines)) { // We've got a new text size and/or max lines... boolean updateTextView = true; if (mMode == MODE_FIXED && textSize > curTextSize && curLineCount == 1) { // If we're in fixed mode, going up in text size and currently have 1 line // then it's very easy to get into an infinite recursion. // To combat that we check to see if the change in text size // will cause a line count change. If so, abort the size change and stick // to the smaller size. final Layout layout = mTextView.getLayout(); if (layout == null || approximateLineWidth(layout, 0, textSize) > getMeasuredWidth() - getPaddingLeft() - getPaddingRight()) { updateTextView = false; } } if (updateTextView) { mTextView.setTextSize(TypedValue.COMPLEX_UNIT_PX, textSize); mTextView.setMaxLines(maxLines); super.onMeasure(widthMeasureSpec, heightMeasureSpec); } } } } private void setTab(@Nullable final Tab tab) { if (tab != mTab) { mTab = tab; update(); } } private void reset() { setTab(null); setSelected(false); } final void update() { final Tab tab = mTab; final View custom = tab != null ? tab.getCustomView() : null; 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); } mCustomTextView = (TextView) custom.findViewById(android.R.id.text1); if (mCustomTextView != null) { mDefaultMaxLines = TextViewCompat.getMaxLines(mCustomTextView); } mCustomIconView = (ImageView) custom.findViewById(android.R.id.icon); } else { // We do not have a custom view. Remove one if it already exists if (mCustomView != null) { removeView(mCustomView); mCustomView = null; } mCustomTextView = null; mCustomIconView = null; } if (mCustomView == null) { // If there isn't a custom view, we'll us our own in-built layouts if (mIconView == null) { ImageView iconView = (ImageView) LayoutInflater.from(getContext()) .inflate(R.layout.design_layout_tab_icon, this, false); addView(iconView, 0); mIconView = iconView; } if (mTextView == null) { TextView textView = (TextView) LayoutInflater.from(getContext()) .inflate(R.layout.design_layout_tab_text, this, false); addView(textView); mTextView = textView; mDefaultMaxLines = TextViewCompat.getMaxLines(mTextView); } mTextView.setTextAppearance(getContext(), mTabTextAppearance); if (mTabTextColors != null) { mTextView.setTextColor(mTabTextColors); } updateTextAndIcon(mTextView, mIconView); } else { // Else, we'll see if there is a TextView or ImageView present and update them if (mCustomTextView != null || mCustomIconView != null) { updateTextAndIcon(mCustomTextView, mCustomIconView); } } // Finally update our selected state setSelected(tab != null && tab.isSelected()); } private void updateTextAndIcon(@Nullable final TextView textView, @Nullable final ImageView iconView) { final Drawable icon = mTab != null ? mTab.getIcon() : null; final CharSequence text = mTab != null ? mTab.getText() : null; final CharSequence contentDesc = mTab != null ? mTab.getContentDescription() : null; if (iconView != null) { if (icon != null) { iconView.setImageDrawable(icon); iconView.setVisibility(VISIBLE); setVisibility(VISIBLE); } else { iconView.setVisibility(GONE); iconView.setImageDrawable(null); } iconView.setContentDescription(contentDesc); } final boolean hasText = !TextUtils.isEmpty(text); if (textView != null) { if (hasText) { textView.setText(text); textView.setVisibility(VISIBLE); setVisibility(VISIBLE); } else { textView.setVisibility(GONE); textView.setText(null); } textView.setContentDescription(contentDesc); } if (iconView != null) { MarginLayoutParams lp = ((MarginLayoutParams) iconView.getLayoutParams()); int bottomMargin = 0; if (hasText && iconView.getVisibility() == VISIBLE) { // If we're showing both text and icon, add some margin bottom to the icon bottomMargin = dpToPx(DEFAULT_GAP_TEXT_ICON); } if (bottomMargin != lp.bottomMargin) { lp.bottomMargin = bottomMargin; iconView.requestLayout(); } } if (!hasText && !TextUtils.isEmpty(contentDesc)) { setOnLongClickListener(this); } else { setOnLongClickListener(null); setLongClickable(false); } } @Override public boolean onLongClick(final View v) { final int[] screenPos = new int[2]; final Rect displayFrame = new Rect(); getLocationOnScreen(screenPos); getWindowVisibleDisplayFrame(displayFrame); final Context context = getContext(); final int width = getWidth(); final int height = getHeight(); final int midy = screenPos[1] + height / 2; int referenceX = screenPos[0] + width / 2; if (ViewCompat.getLayoutDirection(v) == ViewCompat.LAYOUT_DIRECTION_LTR) { final int screenWidth = context.getResources().getDisplayMetrics().widthPixels; referenceX = screenWidth - referenceX; // mirror } Toast cheatSheet = Toast.makeText(context, mTab.getContentDescription(), Toast.LENGTH_SHORT); if (midy < displayFrame.height()) { // Show below the tab view cheatSheet.setGravity(Gravity.TOP | GravityCompat.END, referenceX, screenPos[1] + height - displayFrame.top); } else { // Show along the bottom center cheatSheet.setGravity(Gravity.BOTTOM | Gravity.CENTER_HORIZONTAL, 0, height); } cheatSheet.show(); return true; } public Tab getTab() { return mTab; } /** * Approximates a given lines width with the new provided text size. */ private float approximateLineWidth(Layout layout, int line, float textSize) { return layout.getLineWidth(line) * (textSize / layout.getPaint().getTextSize()); } } private class SlidingTabStrip extends LinearLayout { private int mSelectedIndicatorHeight; private final Paint mSelectedIndicatorPaint; private int mSelectedPosition = -1; private float mSelectionOffset; private int mIndicatorLeft = -1; private int mIndicatorRight = -1; private ValueAnimatorCompat mIndicatorAnimator; SlidingTabStrip(Context context) { super(context); setWillNotDraw(false); mSelectedIndicatorPaint = new Paint(); } void setSelectedIndicatorColor(int color) { if (mSelectedIndicatorPaint.getColor() != color) { mSelectedIndicatorPaint.setColor(color); ViewCompat.postInvalidateOnAnimation(this); } } void setSelectedIndicatorHeight(int height) { if (mSelectedIndicatorHeight != height) { mSelectedIndicatorHeight = height; ViewCompat.postInvalidateOnAnimation(this); } } boolean childrenNeedLayout() { for (int i = 0, z = getChildCount(); i < z; i++) { final View child = getChildAt(i); if (child.getWidth() <= 0) { return true; } } return false; } void setIndicatorPositionFromTabPosition(int position, float positionOffset) { if (mIndicatorAnimator != null && mIndicatorAnimator.isRunning()) { mIndicatorAnimator.cancel(); } mSelectedPosition = position; mSelectionOffset = positionOffset; updateIndicatorPosition(); } float getIndicatorPosition() { return mSelectedPosition + mSelectionOffset; } @Override protected void onMeasure(final int widthMeasureSpec, final int heightMeasureSpec) { super.onMeasure(widthMeasureSpec, heightMeasureSpec); if (MeasureSpec.getMode(widthMeasureSpec) != MeasureSpec.EXACTLY) { // HorizontalScrollView will first measure use with UNSPECIFIED, and then with // EXACTLY. Ignore the first call since anything we do will be overwritten anyway return; } if (mMode == MODE_FIXED && mTabGravity == GRAVITY_CENTER) { final int count = getChildCount(); // First we'll find the widest tab int largestTabWidth = 0; for (int i = 0, z = count; i < z; i++) { View child = getChildAt(i); if (child.getVisibility() == VISIBLE) { largestTabWidth = Math.max(largestTabWidth, child.getMeasuredWidth()); } } if (largestTabWidth <= 0) { // If we don't have a largest child yet, skip until the next measure pass return; } final int gutter = dpToPx(FIXED_WRAP_GUTTER_MIN); boolean remeasure = false; if (largestTabWidth * count <= getMeasuredWidth() - gutter * 2) { // If the tabs fit within our width minus gutters, we will set all tabs to have // the same width for (int i = 0; i < count; i++) { final LinearLayout.LayoutParams lp = (LayoutParams) getChildAt(i).getLayoutParams(); if (lp.width != largestTabWidth || lp.weight != 0) { lp.width = largestTabWidth; lp.weight = 0; remeasure = true; } } } else { // If the tabs will wrap to be larger than the width minus gutters, we need // to switch to GRAVITY_FILL mTabGravity = GRAVITY_FILL; updateTabViews(false); remeasure = true; } if (remeasure) { // Now re-measure after our changes super.onMeasure(widthMeasureSpec, heightMeasureSpec); } } } @Override protected void onLayout(boolean changed, int l, int t, int r, int b) { super.onLayout(changed, l, t, r, b); if (mIndicatorAnimator != null && mIndicatorAnimator.isRunning()) { // If we're currently running an animation, lets cancel it and start a // new animation with the remaining duration mIndicatorAnimator.cancel(); final long duration = mIndicatorAnimator.getDuration(); animateIndicatorToPosition(mSelectedPosition, Math.round((1f - mIndicatorAnimator.getAnimatedFraction()) * duration)); } else { // If we've been layed out, update the indicator position updateIndicatorPosition(); } } private void updateIndicatorPosition() { final View selectedTitle = getChildAt(mSelectedPosition); int left, right; if (selectedTitle != null && selectedTitle.getWidth() > 0) { left = selectedTitle.getLeft(); right = selectedTitle.getRight(); if (mSelectionOffset > 0f && mSelectedPosition < getChildCount() - 1) { // Draw the selection partway between the tabs View nextTitle = getChildAt(mSelectedPosition + 1); left = (int) (mSelectionOffset * nextTitle.getLeft() + (1.0f - mSelectionOffset) * left); right = (int) (mSelectionOffset * nextTitle.getRight() + (1.0f - mSelectionOffset) * right); } } else { left = right = -1; } setIndicatorPosition(left, right); } private void setIndicatorPosition(int left, int right) { if (left != mIndicatorLeft || right != mIndicatorRight) { // If the indicator's left/right has changed, invalidate mIndicatorLeft = left; mIndicatorRight = right; ViewCompat.postInvalidateOnAnimation(this); } } void animateIndicatorToPosition(final int position, int duration) { if (mIndicatorAnimator != null && mIndicatorAnimator.isRunning()) { mIndicatorAnimator.cancel(); } final boolean isRtl = ViewCompat.getLayoutDirection(this) == ViewCompat.LAYOUT_DIRECTION_RTL; final View targetView = getChildAt(position); if (targetView == null) { // If we don't have a view, just update the position now and return updateIndicatorPosition(); return; } final int targetLeft = targetView.getLeft(); final int targetRight = targetView.getRight(); final int startLeft; final int startRight; if (Math.abs(position - mSelectedPosition) <= 1) { // If the views are adjacent, we'll animate from edge-to-edge startLeft = mIndicatorLeft; startRight = mIndicatorRight; } else { // Else, we'll just grow from the nearest edge final int offset = dpToPx(MOTION_NON_ADJACENT_OFFSET); if (position < mSelectedPosition) { // We're going end-to-start if (isRtl) { startLeft = startRight = targetLeft - offset; } else { startLeft = startRight = targetRight + offset; } } else { // We're going start-to-end if (isRtl) { startLeft = startRight = targetRight + offset; } else { startLeft = startRight = targetLeft - offset; } } } if (startLeft != targetLeft || startRight != targetRight) { ValueAnimatorCompat animator = mIndicatorAnimator = ViewUtils.createAnimator(); animator.setInterpolator(AnimationUtils.FAST_OUT_SLOW_IN_INTERPOLATOR); animator.setDuration(duration); animator.setFloatValues(0, 1); animator.setUpdateListener(new ValueAnimatorCompat.AnimatorUpdateListener() { @Override public void onAnimationUpdate(ValueAnimatorCompat animator) { final float fraction = animator.getAnimatedFraction(); setIndicatorPosition( AnimationUtils.lerp(startLeft, targetLeft, fraction), AnimationUtils.lerp(startRight, targetRight, fraction)); } }); animator.setListener(new ValueAnimatorCompat.AnimatorListenerAdapter() { @Override public void onAnimationEnd(ValueAnimatorCompat animator) { mSelectedPosition = position; mSelectionOffset = 0f; } }); animator.start(); } } @Override public void draw(Canvas canvas) { super.draw(canvas); // Thick colored underline below the current selection if (mIndicatorLeft >= 0 && mIndicatorRight > mIndicatorLeft) { canvas.drawRect(mIndicatorLeft, getHeight() - mSelectedIndicatorHeight, mIndicatorRight, getHeight(), mSelectedIndicatorPaint); } } } private static ColorStateList createColorStateList(int defaultColor, int selectedColor) { final int[][] states = new int[2][]; final int[] colors = new int[2]; int i = 0; states[i] = SELECTED_STATE_SET; colors[i] = selectedColor; i++; // Default enabled state states[i] = EMPTY_STATE_SET; colors[i] = defaultColor; i++; return new ColorStateList(states, colors); } private int getDefaultHeight() { boolean hasIconAndText = false; for (int i = 0, count = mTabs.size(); i < count; i++) { Tab tab = mTabs.get(i); if (tab != null && tab.getIcon() != null && !TextUtils.isEmpty(tab.getText())) { hasIconAndText = true; break; } } return hasIconAndText ? DEFAULT_HEIGHT_WITH_TEXT_ICON : DEFAULT_HEIGHT; } private int getTabMinWidth() { if (mRequestedTabMinWidth != INVALID_WIDTH) { // If we have been given a min width, use it return mRequestedTabMinWidth; } // Else, we'll use the default value return mMode == MODE_SCROLLABLE ? mScrollableTabMinWidth : 0; } @Override public LayoutParams generateLayoutParams(AttributeSet attrs) { // We don't care about the layout params of any views added to us, since we don't actually // add them. The only view we add is the SlidingTabStrip, which is done manually. // We return the default layout params so that we don't blow up if we're given a TabItem // without android:layout_* values. return generateDefaultLayoutParams(); } private int getTabMaxWidth() { return mTabMaxWidth; } /** * A {@link ViewPager.OnPageChangeListener} class which contains the * necessary calls back to the provided {@link TabLayout} so that the tab position is * kept in sync. * *This class stores the provided TabLayout weakly, meaning that you can use
* {@link ViewPager#addOnPageChangeListener(ViewPager.OnPageChangeListener)
* addOnPageChangeListener(OnPageChangeListener)} without removing the listener and
* not cause a leak.
*/
public static class TabLayoutOnPageChangeListener implements ViewPager.OnPageChangeListener {
private final WeakReference