Java tutorial
/* * Copyright (C) 2013 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 com.axolotl.yanews.customize; import android.annotation.TargetApi; import android.content.Context; import android.graphics.Color; 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.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.axolotl.yanews.R; import com.axolotl.yanews.utils.TextViewUtil; /** * To be used with ViewPager to provide a tab indicator component which give constant feedback as to * the user's scroll progress. * <p> * To use the component, simply add it to your view hierarchy. Then in your * {@link android.app.Activity} or {@link android.support.v4.app.Fragment} call * {@link #setViewPager(ViewPager)} providing it the ViewPager this layout is being used for. * <p> * The colors can be customized in two ways. The first and simplest is to provide an array of colors * via {@link #setSelectedIndicatorColors(int...)} and {@link #setDividerColors(int...)}. The * alternative is via the {@link TabColorizer} interface which provides you complete control over * which color is used for any individual position. * <p> * The views used as tabs can be customized by calling {@link #setCustomTabView(int, int)}, * providing the layout ID of your custom layout. */ public class SlidingTabLayout extends HorizontalScrollView { /** * 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); } /** * ??dp */ private static final int TITLE_OFFSET_DIPS = 24; private static final int TAB_VIEW_PADDING_DIPS = 10; /** * tab? */ public static int mTab_text_size_sp = 12; private int mTitleOffset; private int mTabViewLayoutId; private int mTabViewTextViewId; private View[] mTabViews; private boolean mDistributeEvenly; /** * ? */ private boolean mBold; private boolean mChangeTextColor; private int mNormalColor; private int mHightColor; private int mBackgroundResource = R.drawable.btn_pressed_selector; private ViewPager mViewPager; private ViewPager.OnPageChangeListener mViewPagerPageChangeListener; private final SlidingTabStrip mTabStrip; private static int[] TAB_TEXT_COLORS = null; public SlidingTabLayout(Context context) { this(context, null); } public SlidingTabLayout(Context context, AttributeSet attrs) { this(context, attrs, 0); } public SlidingTabLayout(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); mTitleOffset = (int) (TITLE_OFFSET_DIPS * getResources().getDisplayMetrics().density); mTabStrip = new SlidingTabStrip(context); addView(mTabStrip, ViewGroup.LayoutParams.MATCH_PARENT, ViewGroup.LayoutParams.MATCH_PARENT); } /** * ? * @param size sp */ public void setTabTextSize(int size) { mTab_text_size_sp = size; } public void setTabTextBold(boolean bold) { mBold = bold; } public void setTabSelector(int s) { mBackgroundResource = s; mTabStrip.removeAllViews(); if (mViewPager != null) { populateTabStrip(); } } /** * tab? * @param normal * @param highlight */ public void setTabTextColor(int normal, int highlight) { mChangeTextColor = true; mNormalColor = normal; mHightColor = highlight; mTabStrip.removeAllViews(); if (mViewPager != null) { populateTabStrip(); } } /** * Set the custom {@link TabColorizer} to be used. * * If you only require simple custmisation then you can use * {@link #setSelectedIndicatorColors(int...)} and {@link #setDividerColors(int...)} to achieve * similar effects. */ public void setCustomTabColorizer(TabColorizer tabColorizer) { mTabStrip.setCustomTabColorizer(tabColorizer); } /** * 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. * @param colors */ public void setSelectedIndicatorColors(int... colors) { mTabStrip.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. * @param colors */ public void setDividerColors(int... colors) { mTabStrip.setDividerColors(colors); } /** * indicator * @param height px */ public void setIndicatorHeight(int height) { mTabStrip.setSelectedIndicatorHeight(height); } /** * Set the {@link ViewPager.OnPageChangeListener}. {@link SlidingTabLayout} * {@link ViewPager.OnPageChangeListener} . This is so * that the layout can update it's scroll position correctly. * * @see ViewPager#setOnPageChangeListener(ViewPager.OnPageChangeListener) */ public void setOnPageChangeListener(ViewPager.OnPageChangeListener listener) { mViewPagerPageChangeListener = listener; } /** * tab? * @param distributeEvenly */ public void setDistributeEvenly(boolean distributeEvenly) { mDistributeEvenly = distributeEvenly; } /** * Set the custom layout to be inflated for the tab views. * * @param layoutResId Layout id to be inflated * @param textViewId id of the {@link TextView} in the inflated view */ public void setCustomTabView(int layoutResId, int textViewId) { mTabViewLayoutId = layoutResId; mTabViewTextViewId = textViewId; } /** * viewpager, ?? * 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) { mTabStrip.removeAllViews(); mViewPager = viewPager; if (viewPager != null) { viewPager.setOnPageChangeListener(new InternalViewPagerListener()); populateTabStrip(); } } /** * tabview. tab view * {@link #setCustomTabView(int, int)}. */ @TargetApi(Build.VERSION_CODES.ICE_CREAM_SANDWICH) protected TextView createDefaultTabView(Context context) { TextView textView = new TextView(context, null, 0); textView.setGravity(Gravity.CENTER); textView.setTextSize(TypedValue.COMPLEX_UNIT_SP, mTab_text_size_sp); if (mBold) { textView.setTypeface(Typeface.DEFAULT, Typeface.BOLD); } else { textView.setTypeface(Typeface.DEFAULT, Typeface.NORMAL); } if (mChangeTextColor) { textView.setTextColor(mNormalColor); } textView.setLayoutParams(new LinearLayout.LayoutParams(LinearLayout.LayoutParams.WRAP_CONTENT, LinearLayout.LayoutParams.MATCH_PARENT)); if (mBackgroundResource != 0) { textView.setBackgroundResource(mBackgroundResource); } 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); } } //wtf // 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(true); // } int padding = (int) (TAB_VIEW_PADDING_DIPS * getResources().getDisplayMetrics().density); textView.setPadding(padding, 0, padding, 0); return textView; } /** * tabtabstrip */ private void populateTabStrip() { final PagerAdapter adapter = mViewPager.getAdapter(); final OnClickListener tabClickListener = new TabClickListener(); mTabViews = null; mTabViews = new View[adapter.getCount()]; for (int i = 0; i < adapter.getCount(); i++) { View tabView = null; TextView tabTitleView = null; if (mTabViewLayoutId != 0) { // If there is a custom tab view layout id set, try and inflate it tabView = LayoutInflater.from(getContext()).inflate(mTabViewLayoutId, mTabStrip, false); tabTitleView = (TextView) tabView.findViewById(mTabViewTextViewId); } if (tabView == null) { tabView = createDefaultTabView(getContext()); } if (tabTitleView == null && TextView.class.isInstance(tabView)) { tabTitleView = (TextView) tabView; } if (mDistributeEvenly) { LinearLayout.LayoutParams lp = (LinearLayout.LayoutParams) tabView.getLayoutParams(); lp.width = 0; lp.weight = 1; } tabTitleView.setText(adapter.getPageTitle(i)); tabView.setOnClickListener(tabClickListener); mTabViews[i] = tabView; mTabStrip.addView(tabView); } } public View getTabAt(int index) { return mTabViews[index]; } /** * viewpager? */ @Override protected void onAttachedToWindow() { super.onAttachedToWindow(); if (mViewPager != null) { scrollToTab(mViewPager.getCurrentItem(), 0); } } private int mLastScrollTo; private void scrollToTab(int tabIndex, int positionOffset) { final int tabStripChildCount = mTabStrip.getChildCount(); if (tabStripChildCount == 0 || tabIndex < 0 || tabIndex >= tabStripChildCount) { return; } View selectedChild = mTabStrip.getChildAt(tabIndex); if (selectedChild != null && selectedChild.getMeasuredWidth() != 0) { int targetScrollX = ((positionOffset + selectedChild.getLeft()) - getWidth() / 2) + selectedChild.getWidth() / 2; if (targetScrollX != mLastScrollTo) { scrollTo(targetScrollX, 0); mLastScrollTo = targetScrollX; } } } /** * ?bottom border ________ * @param enable */ public void setBottomBorderEnbaled(boolean enable) { mTabStrip.setBottomBorderEnabled(enable); } /** * ?divider | * @param enable */ public void setDividerEnabled(boolean enable) { mTabStrip.setDividerEnabled(enable); } private class InternalViewPagerListener implements ViewPager.OnPageChangeListener { private int mScrollState; @Override public void onPageScrolled(int position, float positionOffset, int positionOffsetPixels) { int tabStripChildCount = mTabStrip.getChildCount(); if ((tabStripChildCount == 0) || (position < 0) || (position >= tabStripChildCount)) { return; } mTabStrip.onViewPagerPageChanged(position, positionOffset); View selectedTitle = mTabStrip.getChildAt(position); int selectedOffset = (selectedTitle == null) ? 0 : selectedTitle.getWidth(); int nextTitlePosition = position + 1; View nextTitle = mTabStrip.getChildAt(nextTitlePosition); int nextOffset = (nextTitle == null) ? 0 : nextTitle.getWidth(); int extraOffset = (int) (0.5F * (positionOffset * (float) (selectedOffset + nextOffset))); scrollToTab(position, extraOffset); if (mViewPagerPageChangeListener != null) { mViewPagerPageChangeListener.onPageScrolled(position, positionOffset, positionOffsetPixels); } } @Override public void onPageScrollStateChanged(int state) { mScrollState = state; if (mScrollState == ViewPager.SCROLL_STATE_IDLE) { int count = mTabStrip.getChildCount(); int curItem = mViewPager.getCurrentItem(); for (int i = 0; i < count; i++) { // by neo View tabView = SlidingTabLayout.this.getTabAt(i); if (i == curItem) { TextViewUtil.setTextColor(tabView, mNormalColor); tabView.setBackgroundColor(getColorByIndex(i)); } else { TextViewUtil.setTextColor(tabView, getColorByIndex(i)); tabView.setBackgroundColor(Color.TRANSPARENT); } } } if (mViewPagerPageChangeListener != null) { mViewPagerPageChangeListener.onPageScrollStateChanged(state); } } @Override public void onPageSelected(int position) { int count = mTabStrip.getChildCount(); for (int i = 0; i < count; i++) { // by neo View tabView = SlidingTabLayout.this.getTabAt(i); if (i == position) { // Statistics.statsClickTab(TextViewUtil.getText(tabView)); TextViewUtil.setTextColor(tabView, mNormalColor); tabView.setBackgroundColor(getColorByIndex(i)); } else { TextViewUtil.setTextColor(tabView, getColorByIndex(i)); tabView.setBackgroundColor(Color.TRANSPARENT); } } if (mScrollState == ViewPager.SCROLL_STATE_IDLE) { mTabStrip.onViewPagerPageChanged(position, 0f); scrollToTab(position, 0); } if (mViewPagerPageChangeListener != null) { mViewPagerPageChangeListener.onPageSelected(position); } } } private class TabClickListener implements OnClickListener { @Override public void onClick(View v) { for (int i = 0; i < mTabStrip.getChildCount(); i++) { if (v == mTabStrip.getChildAt(i)) { mViewPager.setCurrentItem(i); return; } } } } public void setCurrentItem(int index) { mViewPager.setCurrentItem(index, false); int count = mTabStrip.getChildCount(); int curItem = mViewPager.getCurrentItem(); for (int i = 0; i < count; i++) { // by neo View tabView = SlidingTabLayout.this.getTabAt(i); if (i == curItem) { TextViewUtil.setTextColor(tabView, mNormalColor); tabView.setBackgroundColor(getColorByIndex(i)); } else { TextViewUtil.setTextColor(tabView, getColorByIndex(i)); tabView.setBackgroundColor(Color.TRANSPARENT); } } } /** * ? * @param index */ private int getColorByIndex(int index) { if (index < 0) { index = 0; } if (null == TAB_TEXT_COLORS) { TAB_TEXT_COLORS = new int[] { getResources().getColor(R.color.orangered), getResources().getColor(R.color.orange), getResources().getColor(R.color.limegreen), getResources().getColor(R.color.deepskyblue), getResources().getColor(R.color.blueviolet) }; } int color = TAB_TEXT_COLORS[index % TAB_TEXT_COLORS.length]; return color; } }