Java tutorial
/** * Copyright (C) 2015 ogaclejapan * Copyright (C) 2013 The Android Open Source Project * <p> * 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 * <p> * http://www.apache.org/licenses/LICENSE-2.0 * <p> * 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 com.jinzht.pro.smarttablayout; import android.content.Context; import android.content.res.ColorStateList; import android.content.res.TypedArray; import android.graphics.Typeface; import android.os.Build; import android.support.v4.view.PagerAdapter; import android.support.v4.view.ViewPager; import android.util.AttributeSet; import android.util.DisplayMetrics; import android.util.TypedValue; import android.view.Gravity; import android.view.LayoutInflater; import android.view.View; import android.view.ViewGroup; import android.widget.HorizontalScrollView; import android.widget.LinearLayout; import android.widget.TextView; import com.jinzht.pro.R; import com.jinzht.pro.utils.UiHelp; /** * To be used with ViewPager to provide a tab indicator component which give constant feedback as */ public class SmartTabLayout extends HorizontalScrollView { private static final boolean DEFAULT_DISTRIBUTE_EVENLY = false; private static final int TITLE_OFFSET_DIPS = 24; private static final int TAB_VIEW_PADDING_DIPS = 16; private static final boolean TAB_VIEW_TEXT_ALL_CAPS = true; private static final int TAB_VIEW_TEXT_SIZE_SP = 14; private static final int TAB_VIEW_TEXT_COLOR = 0xFC000000; private static final int TAB_VIEW_TEXT_MIN_WIDTH = 0; protected final SmartTabStrip tabStrip; private int titleOffset; private int tabViewBackgroundResId; private boolean tabViewTextAllCaps; private ColorStateList tabViewTextColors; private float tabViewTextSize; private int tabViewTextHorizontalPadding; private int tabViewTextMinWidth; private ViewPager viewPager; private ViewPager.OnPageChangeListener viewPagerPageChangeListener; private OnScrollChangeListener onScrollChangeListener; private TabProvider tabProvider; private boolean distributeEvenly; public SmartTabLayout(Context context) { this(context, null); } public SmartTabLayout(Context context, AttributeSet attrs) { this(context, attrs, 0); } public SmartTabLayout(Context context, AttributeSet attrs, int defStyle) { super(context, attrs, defStyle); // Disable the Scroll Bar setHorizontalScrollBarEnabled(false); // Make sure that the Tab Strips fills this View setFillViewport(true); final DisplayMetrics dm = getResources().getDisplayMetrics(); final float density = dm.density; int tabBackgroundResId = NO_ID; boolean textAllCaps = TAB_VIEW_TEXT_ALL_CAPS; ColorStateList textColors; float textSize = TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_SP, TAB_VIEW_TEXT_SIZE_SP, dm); int textHorizontalPadding = (int) (TAB_VIEW_PADDING_DIPS * density); int textMinWidth = (int) (TAB_VIEW_TEXT_MIN_WIDTH * density); boolean distributeEvenly = DEFAULT_DISTRIBUTE_EVENLY; int customTabLayoutId = NO_ID; int customTabTextViewId = NO_ID; TypedArray a = context.obtainStyledAttributes(attrs, R.styleable.stl_SmartTabLayout, defStyle, 0); tabBackgroundResId = a.getResourceId(R.styleable.stl_SmartTabLayout_stl_defaultTabBackground, tabBackgroundResId); textAllCaps = a.getBoolean(R.styleable.stl_SmartTabLayout_stl_defaultTabTextAllCaps, textAllCaps); textColors = a.getColorStateList(R.styleable.stl_SmartTabLayout_stl_defaultTabTextColor); textSize = a.getDimension(R.styleable.stl_SmartTabLayout_stl_defaultTabTextSize, textSize); textHorizontalPadding = a.getDimensionPixelSize( R.styleable.stl_SmartTabLayout_stl_defaultTabTextHorizontalPadding, textHorizontalPadding); textMinWidth = a.getDimensionPixelSize(R.styleable.stl_SmartTabLayout_stl_defaultTabTextMinWidth, textMinWidth); customTabLayoutId = a.getResourceId(R.styleable.stl_SmartTabLayout_stl_customTabTextLayoutId, customTabLayoutId); customTabTextViewId = a.getResourceId(R.styleable.stl_SmartTabLayout_stl_customTabTextViewId, customTabTextViewId); distributeEvenly = a.getBoolean(R.styleable.stl_SmartTabLayout_stl_distributeEvenly, distributeEvenly); a.recycle(); this.titleOffset = (int) (TITLE_OFFSET_DIPS * density); this.tabViewBackgroundResId = tabBackgroundResId; this.tabViewTextAllCaps = textAllCaps; this.tabViewTextColors = (textColors != null) ? textColors : ColorStateList.valueOf(TAB_VIEW_TEXT_COLOR); this.tabViewTextSize = textSize; this.tabViewTextHorizontalPadding = textHorizontalPadding; this.tabViewTextMinWidth = textMinWidth; this.distributeEvenly = distributeEvenly; if (customTabLayoutId != NO_ID) { setCustomTabView(customTabLayoutId, customTabTextViewId); } this.tabStrip = new SmartTabStrip(context, attrs); if (distributeEvenly && tabStrip.isIndicatorAlwaysInCenter()) { throw new UnsupportedOperationException( "'distributeEvenly' and 'indicatorAlwaysInCenter' both use does not support"); } addView(tabStrip, LayoutParams.MATCH_PARENT, LayoutParams.MATCH_PARENT); } @Override protected void onScrollChanged(int l, int t, int oldl, int oldt) { super.onScrollChanged(l, t, oldl, oldt); if (onScrollChangeListener != null) { onScrollChangeListener.onScrollChanged(l, oldl); } } @Override protected void onSizeChanged(int w, int h, int oldw, int oldh) { super.onSizeChanged(w, h, oldw, oldh); if (tabStrip.isIndicatorAlwaysInCenter() && getChildCount() > 0) { View firstTab = tabStrip.getChildAt(0); View lastTab = tabStrip.getChildAt(getChildCount() - 1); int left = (w - Utils.getMeasuredWidth(firstTab)) / 2 - Utils.getMarginStart(firstTab); int right = (w - Utils.getMeasuredWidth(lastTab)) / 2 - Utils.getMarginEnd(lastTab); setPadding(left, getPaddingTop(), right, getPaddingBottom()); setClipToPadding(false); } } /** * Set the behavior of the Indicator scrolling feedback. * */ public void setIndicationInterpolator(SmartTabIndicationInterpolator interpolator) { tabStrip.setIndicationInterpolator(interpolator); } /** * Set the custom {@link TabColorizer} to be used. * similar effects. */ public void setCustomTabColorizer(TabColorizer tabColorizer) { tabStrip.setCustomTabColorizer(tabColorizer); } /** * @param color to use for tab text */ public void setDefaultTabTextColor(int color) { tabViewTextColors = ColorStateList.valueOf(color); } public void setDefaultTabTextColor(ColorStateList colors) { tabViewTextColors = colors; } /** * Set the same weight for tab */ public void setDistributeEvenly(boolean distributeEvenly) { this.distributeEvenly = distributeEvenly; } /** * Sets the colors to be used for indicating the selected tab. These colors are treated as a * circular array. Providing one color will mean that all tabs are indicated with the same color. */ public void setSelectedIndicatorColors(int... colors) { tabStrip.setSelectedIndicatorColors(colors); } /** * Sets the colors to be used for tab dividers. These colors are treated as a circular array. * Providing one color will mean that all tabs are indicated with the same color. */ public void setDividerColors(int... colors) { tabStrip.setDividerColors(colors); } /** */ public void setOnPageChangeListener(ViewPager.OnPageChangeListener listener) { viewPagerPageChangeListener = listener; } /** * Set {@link OnScrollChangeListener} for obtaining values of scrolling. * @param listener the {@link OnScrollChangeListener} to set */ public void setOnScrollChangeListener(OnScrollChangeListener listener) { onScrollChangeListener = listener; } /** */ public void setCustomTabView(int layoutResId, int textViewId) { tabProvider = new SimpleTabProvider(getContext(), layoutResId, textViewId); } /** */ public void setCustomTabView(TabProvider provider) { tabProvider = provider; } /** * Sets the associated view pager. Note that the assumption here is that the pager content * (number of tabs and tab titles) does not change after this call has been made. */ public void setViewPager(ViewPager viewPager) { tabStrip.removeAllViews(); this.viewPager = viewPager; viewPager.setOffscreenPageLimit(10); if (viewPager != null && viewPager.getAdapter() != null) { viewPager.setOnPageChangeListener(new InternalViewPagerListener()); populateTabStrip(); } } /** * Returns the view at the specified position in the tabs. * * @param position the position at which to get the view from * @return the view at the specified position or null if the position does not exist within the * tabs */ public View getTabAt(int position) { return tabStrip.getChildAt(position); } /** * Create a default view to be used for tabs. This is called if a custom tab view is not set via * {@link #setCustomTabView(int, int)}. */ protected TextView createDefaultTabView(CharSequence title) { TextView textView = new TextView(getContext()); textView.setGravity(Gravity.CENTER); textView.setText(title); textView.setTextColor(tabViewTextColors); textView.setTextSize(TypedValue.COMPLEX_UNIT_PX, tabViewTextSize); textView.setTypeface(Typeface.DEFAULT_BOLD); textView.setSingleLine(true); UiHelp.textBold(textView); textView.setLayoutParams(new LinearLayout.LayoutParams(LinearLayout.LayoutParams.WRAP_CONTENT, LinearLayout.LayoutParams.MATCH_PARENT)); if (tabViewBackgroundResId != NO_ID) { textView.setBackgroundResource(tabViewBackgroundResId); } else if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.HONEYCOMB) { // If we're running on Honeycomb or newer, then we can use the Theme's // selectableItemBackground to ensure that the View has a pressed state TypedValue outValue = new TypedValue(); getContext().getTheme().resolveAttribute(android.R.attr.selectableItemBackground, outValue, true); textView.setBackgroundResource(outValue.resourceId); } if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.ICE_CREAM_SANDWICH) { // If we're running on ICS or newer, enable all-caps to match the Action Bar tab style textView.setAllCaps(tabViewTextAllCaps); } textView.setPadding(tabViewTextHorizontalPadding, 0, tabViewTextHorizontalPadding, 0); if (tabViewTextMinWidth > 0) { textView.setMinWidth(tabViewTextMinWidth); } return textView; } private void populateTabStrip() { final PagerAdapter adapter = viewPager.getAdapter(); final OnClickListener tabClickListener = new TabClickListener(); for (int i = 0; i < adapter.getCount(); i++) { final View tabView = (tabProvider == null) ? createDefaultTabView(adapter.getPageTitle(i)) : tabProvider.createTabView(tabStrip, i, adapter); if (tabView == null) { throw new IllegalStateException("tabView is null."); } if (distributeEvenly) { LinearLayout.LayoutParams lp = (LinearLayout.LayoutParams) tabView.getLayoutParams(); lp.width = 0; lp.weight = 1; } tabView.setOnClickListener(tabClickListener); tabStrip.addView(tabView); if (i == viewPager.getCurrentItem()) { tabView.setSelected(true); } } } @Override protected void onAttachedToWindow() { super.onAttachedToWindow(); if (viewPager != null) { scrollToTab(viewPager.getCurrentItem(), 0); } } private void scrollToTab(int tabIndex, int positionOffset) { final int tabStripChildCount = tabStrip.getChildCount(); if (tabStripChildCount == 0 || tabIndex < 0 || tabIndex >= tabStripChildCount) { return; } View selectedTab = tabStrip.getChildAt(tabIndex); if (selectedTab != null) { int targetScrollX = Utils.getLeft(selectedTab) - Utils.getMarginStart(selectedTab) + positionOffset; if (tabStrip.isIndicatorAlwaysInCenter()) { View firstTab = tabStrip.getChildAt(0); int first = Utils.getWidth(firstTab) + Utils.getMarginStart(firstTab); int selected = Utils.getWidth(selectedTab) + Utils.getMarginStart(selectedTab); targetScrollX -= (first - selected) / 2; } else if (tabIndex > 0 || positionOffset > 0) { // If we're not at the first child and are mid-scroll, make sure we obey the offset targetScrollX -= titleOffset; } scrollTo(targetScrollX, 0); } } /** * Allows complete control over the colors drawn in the tab layout. Set with * {@link #setCustomTabColorizer(TabColorizer)}. */ public interface TabColorizer { /** * @return return the color of the indicator used when {@code position} is selected. */ int getIndicatorColor(int position); /** * @return return the color of the divider drawn to the right of {@code position}. */ int getDividerColor(int position); } /** * Interface definition for a callback to be invoked when the scroll position of a view changes. */ public interface OnScrollChangeListener { /** * Called when the scroll position of a view changes. * @param scrollX Current horizontal scroll origin. * @param oldScrollX Previous horizontal scroll origin. */ void onScrollChanged(int scrollX, int oldScrollX); } public interface TabProvider { /** * @return Return the View of {@code position} for the Tabs */ View createTabView(ViewGroup container, int position, PagerAdapter adapter); } private static class SimpleTabProvider implements TabProvider { private final LayoutInflater inflater; private final int tabViewLayoutId; private final int tabViewTextViewId; private SimpleTabProvider(Context context, int layoutResId, int textViewId) { inflater = LayoutInflater.from(context); tabViewLayoutId = layoutResId; tabViewTextViewId = textViewId; } @Override public View createTabView(ViewGroup container, int position, PagerAdapter adapter) { View tabView = null; TextView tabTitleView = null; if (tabViewLayoutId != NO_ID) { tabView = inflater.inflate(tabViewLayoutId, container, false); } if (tabViewTextViewId != NO_ID && tabView != null) { tabTitleView = (TextView) tabView.findViewById(tabViewTextViewId); } if (tabTitleView == null && TextView.class.isInstance(tabView)) { tabTitleView = (TextView) tabView; } if (tabTitleView != null) { tabTitleView.setText(adapter.getPageTitle(position)); } return tabView; } } private class InternalViewPagerListener implements ViewPager.OnPageChangeListener { private int scrollState; @Override public void onPageScrolled(int position, float positionOffset, int positionOffsetPixels) { int tabStripChildCount = tabStrip.getChildCount(); if ((tabStripChildCount == 0) || (position < 0) || (position >= tabStripChildCount)) { return; } tabStrip.onViewPagerPageChanged(position, positionOffset); View selectedTab = tabStrip.getChildAt(position); int widthPlusMargin = Utils.getWidth(selectedTab) + Utils.getMarginHorizontally(selectedTab); int extraOffset = (int) (positionOffset * widthPlusMargin); if (0f < positionOffset && positionOffset < 1f && tabStrip.isIndicatorAlwaysInCenter()) { View currentTab = tabStrip.getChildAt(position); View nextTab = tabStrip.getChildAt(position + 1); int current = Utils.getWidth(currentTab) / 2 + Utils.getMarginEnd(currentTab); int next = Utils.getWidth(nextTab) / 2 + Utils.getMarginStart(nextTab); extraOffset = Math.round(positionOffset * (current + next)); } scrollToTab(position, extraOffset); if (viewPagerPageChangeListener != null) { viewPagerPageChangeListener.onPageScrolled(position, positionOffset, positionOffsetPixels); } } @Override public void onPageScrollStateChanged(int state) { scrollState = state; if (viewPagerPageChangeListener != null) { viewPagerPageChangeListener.onPageScrollStateChanged(state); } } @Override public void onPageSelected(int position) { if (scrollState == ViewPager.SCROLL_STATE_IDLE) { tabStrip.onViewPagerPageChanged(position, 0f); scrollToTab(position, 0); } for (int i = 0, size = tabStrip.getChildCount(); i < size; i++) { tabStrip.getChildAt(i).setSelected(position == i); } if (viewPagerPageChangeListener != null) { viewPagerPageChangeListener.onPageSelected(position); } } } private class TabClickListener implements OnClickListener { @Override public void onClick(View v) { for (int i = 0; i < tabStrip.getChildCount(); i++) { if (v == tabStrip.getChildAt(i)) { viewPager.setCurrentItem(i); return; } } } } }