Java tutorial
/* * Copyright (C) 2011 The Android Open Source Project * Copyright (C) 2011 Jake Wharton * * 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.viewpagerindicator; import static android.view.ViewGroup.LayoutParams.MATCH_PARENT; import static android.view.ViewGroup.LayoutParams.WRAP_CONTENT; import java.util.HashMap; import android.annotation.SuppressLint; import android.content.Context; import android.graphics.Color; import android.graphics.Typeface; import android.support.v4.view.PagerAdapter; import android.support.v4.view.ViewPager; import android.support.v4.view.ViewPager.OnPageChangeListener; import android.text.Spannable; import android.text.SpannableStringBuilder; import android.text.TextPaint; import android.text.style.ForegroundColorSpan; import android.text.style.StyleSpan; import android.util.AttributeSet; import android.view.Gravity; import android.view.LayoutInflater; import android.view.View; import android.view.ViewGroup; import android.widget.HorizontalScrollView; import android.widget.ImageView; import android.widget.LinearLayout; import android.widget.TextView; import com.android.library.R; /** * This widget implements the dynamic action bar tab behavior that can change * across different configurations or circumstances. */ public class TabTextPageIndicator extends HorizontalScrollView implements PageIndicator { /** * Title text used when no title is provided by the adapter. */ private static final CharSequence EMPTY_TITLE = ""; private final IcsLinearLayout mTabLayout; private Runnable mTabSelector; private ViewPager mViewPager; private OnPageChangeListener mListener; private int mMaxTabWidth; private int mSelectedTabIndex; private OnTabReselectedListener mTabReselectedListener; private final OnClickListener mTabClickListener = new OnClickListener() { public void onClick(View view) { TabView tabView = (TabView) view; final int oldSelected = mViewPager.getCurrentItem(); final int newSelected = tabView.getIndex(); mViewPager.setCurrentItem(newSelected); if (oldSelected == newSelected && mTabReselectedListener != null) { mTabReselectedListener.onTabReselected(newSelected); } } }; private boolean isLayoutWeight = false;// ?? @SuppressLint("UseSparseArrays") private HashMap<Integer, Boolean> newsCirle = new HashMap<Integer, Boolean>();// ? public TabTextPageIndicator(Context context) { this(context, null); } public TabTextPageIndicator(Context context, AttributeSet attrs) { super(context, attrs); setHorizontalScrollBarEnabled(false); mTabLayout = new IcsLinearLayout(context); addView(mTabLayout, new ViewGroup.LayoutParams(WRAP_CONTENT, MATCH_PARENT)); } public boolean getNewsCirle(int index) { if (newsCirle.get(index) == null) { return false; } return newsCirle.get(index); } public void setNewsCirle(int index, boolean isNews) { newsCirle.put(index, isNews); } public void setLayoutWeight(boolean isLayoutWeight) { this.isLayoutWeight = isLayoutWeight; } public void setOnTabReselectedListener(OnTabReselectedListener listener) { mTabReselectedListener = listener; } @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; } } else { mMaxTabWidth = -1; } 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. setCurrentItem(mSelectedTabIndex); } } private void animateToTab(final int position) { final View tabView = mTabLayout.getChildAt(position); if (mTabSelector != null) { removeCallbacks(mTabSelector); } mTabSelector = new Runnable() { 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); } } private void addTab(int index, CharSequence text, int layoutID, boolean showLine) { final TabView tabView = new TabView(getContext()); tabView.mIndex = index; tabView.setOnClickListener(mTabClickListener); View view = LayoutInflater.from(getContext()).inflate(R.layout.lib_layout_viewpagerindicator_pager_title, null); TextView tv = (TextView) view.findViewById(R.id.lib_id_viewpagerindicator_pager_title); tv.setText(text); // // tv.getPaint().setFakeBoldText(true); setTextColor(tv); ImageView newsIv = (ImageView) view.findViewById(R.id.lib_id_viewpagerindicator_pager_news); if (getNewsCirle(index)) { newsIv.setVisibility(View.VISIBLE); } ImageView line = (ImageView) view.findViewById(R.id.lib_id_viewpagerindicator_pager_line); if (!showLine) { line.setVisibility(View.INVISIBLE); } tabView.addView(view); tabView.setGravity(Gravity.CENTER); if (isLayoutWeight) { mTabLayout.addView(tabView, new LinearLayout.LayoutParams(0, WRAP_CONTENT, 1)); } else { mTabLayout.addView(tabView, new LinearLayout.LayoutParams(WRAP_CONTENT, WRAP_CONTENT)); } } @Override public void onPageScrollStateChanged(int arg0) { if (mListener != null) { mListener.onPageScrollStateChanged(arg0); } } @Override public void onPageScrolled(int arg0, float arg1, int arg2) { if (mListener != null) { mListener.onPageScrolled(arg0, arg1, arg2); } } @Override public void onPageSelected(int arg0) { setCurrentItem(arg0); if (mListener != null) { mListener.onPageSelected(arg0); } } @Override public void setViewPager(ViewPager view) { if (mViewPager == view) { return; } if (mViewPager != null) { mViewPager.setOnPageChangeListener(null); } final PagerAdapter adapter = view.getAdapter(); if (adapter == null) { throw new IllegalStateException("ViewPager does not have adapter instance."); } mViewPager = view; view.setOnPageChangeListener(this); notifyDataSetChanged(); } public void notifyDataSetChanged() { mTabLayout.removeAllViews(); PagerAdapter adapter = mViewPager.getAdapter(); IconPagerAdapter iconAdapter = null; if (adapter instanceof IconPagerAdapter) { iconAdapter = (IconPagerAdapter) adapter; } final int count = adapter.getCount(); for (int i = 0; i < count; i++) { CharSequence title = adapter.getPageTitle(i); if (title == null) { title = EMPTY_TITLE; } int layoutID = 0; if (iconAdapter != null) { layoutID = iconAdapter.getIconResId(i); } if (i == count - 1) { addTab(i, title, layoutID, false); } else { addTab(i, title, layoutID, true); } } if (mSelectedTabIndex > count) { mSelectedTabIndex = count - 1; } setCurrentItem(mSelectedTabIndex); requestLayout(); } @Override public void setViewPager(ViewPager view, int initialPosition) { setViewPager(view); setCurrentItem(initialPosition); } @Override public void setCurrentItem(int item) { if (mViewPager == null) { throw new IllegalStateException("ViewPager has not been bound."); } mSelectedTabIndex = item; mViewPager.setCurrentItem(item); final int tabCount = mTabLayout.getChildCount(); for (int i = 0; i < tabCount; i++) { final View child = mTabLayout.getChildAt(i); final boolean isSelected = (i == item); child.setSelected(isSelected); if (isSelected) { animateToTab(item); } } } @Override public void setOnPageChangeListener(OnPageChangeListener listener) { mListener = listener; } /** * textview * * @param textView */ private void setTextColor(TextView textView) { if (textView == null) { return; } String textString = textView.getText().toString(); if (textString.isEmpty()) { return; } int start = textString.indexOf("("); int end = textString.indexOf(")"); if (start < 0 || end < 0 || end < start) { return; } SpannableStringBuilder builder = new SpannableStringBuilder(textString); // ForegroundColorSpan ?BackgroundColorSpan ForegroundColorSpan redSpan = new ForegroundColorSpan(Color.parseColor("#39a5ec")); builder.setSpan(redSpan, start, end + 1, Spannable.SPAN_EXCLUSIVE_EXCLUSIVE); // ? builder.setSpan(new MyStyleSpan(Typeface.NORMAL), start, end + 1, Spannable.SPAN_EXCLUSIVE_EXCLUSIVE); textView.setText(builder); } /** * Interface for a callback when the selected tab has been reselected. */ public interface OnTabReselectedListener { /** * Callback when the selected tab has been reselected. * * @param position Position of the current center item. */ void onTabReselected(int position); } private class TabView extends LinearLayout { private int mIndex; public TabView(Context context) { super(context); } public TabView(Context context, AttributeSet attrs) { super(context, attrs); } @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 int getIndex() { return mIndex; } } class MyStyleSpan extends StyleSpan { public MyStyleSpan(int style) { super(style); } @Override public void updateDrawState(TextPaint ds) { ds.setFakeBoldText(false); super.updateDrawState(ds); } @Override public void updateMeasureState(TextPaint paint) { paint.setFakeBoldText(false); super.updateMeasureState(paint); } } }