Java tutorial
/* * Copyright (C) 2013 Andreas Stuetz <andreas.stuetz@gmail.com> * 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.heqi.kharazim.ui.fragment.tab; import android.annotation.SuppressLint; import android.content.Context; import android.content.res.ColorStateList; import android.content.res.Configuration; import android.content.res.TypedArray; import android.graphics.Canvas; import android.graphics.Paint; import android.graphics.Paint.Style; import android.graphics.Typeface; import android.os.Build; import android.os.Parcel; import android.os.Parcelable; import android.support.v4.view.ViewPager; import android.support.v4.view.ViewPager.OnPageChangeListener; import android.util.AttributeSet; import android.util.DisplayMetrics; import android.util.TypedValue; import android.view.Gravity; import android.view.View; import android.view.ViewTreeObserver.OnGlobalLayoutListener; import android.widget.HorizontalScrollView; import android.widget.LinearLayout; import android.widget.TextView; import com.heqi.kharazim.R; import java.util.Locale; public class PagerSlidingTabStrip extends HorizontalScrollView { private static final int[] ATTRS = new int[] { android.R.attr.textSize, android.R.attr.textColor }; private final PageListener pageListener = new PageListener(); public OnPageChangeListener delegatePageListener; private LinearLayout.LayoutParams defaultTabLayoutParams; private LinearLayout.LayoutParams expandedTabLayoutParams; private LinearLayout tabsContainer; private ViewPager pager; private int tabCount; private int currentPosition = 0; private float currentPositionOffset = 0f; private int currentSelectedPosition = -1; private Paint rectPaint; private Paint dividerPaint; private boolean checkedTabWidths = false; private int indicatorColor = 0xFF666666; private int underlineColor = 0x1A000000; private int dividerColor = 0x1A000000; private boolean shouldExpand = false; private boolean textAllCaps = true; private int scrollOffset = 52; private int indicatorHeight = 8; private int underlineHeight = 2; private int dividerPadding = 12; private int tabPadding = 24; private int dividerWidth = 1; private int tabTextSize = 12; private int tabTextColor = 0xFF666666; private ColorStateList tabTextColorStateList; private Typeface tabTypeface = null; private int tabTypefaceStyle = Typeface.NORMAL; private int lastScrollX = 0; private int tabBackgroundResId = 0; private Locale locale; public PagerSlidingTabStrip(Context context) { this(context, null); } public PagerSlidingTabStrip(Context context, AttributeSet attrs) { this(context, attrs, 0); } public PagerSlidingTabStrip(Context context, AttributeSet attrs, int defStyle) { super(context, attrs, defStyle); setFillViewport(true); setWillNotDraw(false); DisplayMetrics dm = getResources().getDisplayMetrics(); scrollOffset = (int) TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_DIP, scrollOffset, dm); indicatorHeight = (int) TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_DIP, indicatorHeight, dm); underlineHeight = (int) TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_DIP, underlineHeight, dm); dividerPadding = (int) TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_DIP, dividerPadding, dm); tabPadding = (int) TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_DIP, tabPadding, dm); dividerWidth = (int) TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_DIP, dividerWidth, dm); tabTextSize = (int) TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_SP, tabTextSize, dm); // get system attrs (android:textSize and android:textColor) TypedArray a = context.obtainStyledAttributes(attrs, ATTRS); tabTextSize = a.getDimensionPixelSize(0, tabTextSize); tabTextColor = a.getColor(1, tabTextColor); a.recycle(); // get custom attrs a = context.obtainStyledAttributes(attrs, R.styleable.PagerSlidingTabStrip); indicatorColor = a.getColor(R.styleable.PagerSlidingTabStrip_indicatorColor, indicatorColor); underlineColor = a.getColor(R.styleable.PagerSlidingTabStrip_underlineColor, underlineColor); dividerColor = a.getColor(R.styleable.PagerSlidingTabStrip_dividerColor, dividerColor); indicatorHeight = a.getDimensionPixelSize(R.styleable.PagerSlidingTabStrip_indicatorHeight, indicatorHeight); underlineHeight = a.getDimensionPixelSize(R.styleable.PagerSlidingTabStrip_underlineHeight, underlineHeight); dividerPadding = a.getDimensionPixelSize(R.styleable.PagerSlidingTabStrip_TabStripDividerPadding, dividerPadding); tabPadding = a.getDimensionPixelSize(R.styleable.PagerSlidingTabStrip_tabPaddingLeftRight, tabPadding); tabBackgroundResId = a.getResourceId(R.styleable.PagerSlidingTabStrip_tabBackground, tabBackgroundResId); shouldExpand = a.getBoolean(R.styleable.PagerSlidingTabStrip_shouldExpand, shouldExpand); scrollOffset = a.getDimensionPixelSize(R.styleable.PagerSlidingTabStrip_scrollOffset, scrollOffset); textAllCaps = a.getBoolean(R.styleable.PagerSlidingTabStrip_TabStripTextAllCaps, textAllCaps); tabTextColorStateList = a.getColorStateList(R.styleable.PagerSlidingTabStrip_tabTextColor); tabTextSize = a.getDimensionPixelSize(R.styleable.PagerSlidingTabStrip_tabTextSize, tabTextSize); a.recycle(); rectPaint = new Paint(); rectPaint.setAntiAlias(true); rectPaint.setStyle(Style.FILL); dividerPaint = new Paint(); dividerPaint.setAntiAlias(true); dividerPaint.setStrokeWidth(dividerWidth); defaultTabLayoutParams = new LinearLayout.LayoutParams(LayoutParams.WRAP_CONTENT, LayoutParams.MATCH_PARENT); expandedTabLayoutParams = new LinearLayout.LayoutParams(0, LayoutParams.MATCH_PARENT, 1.0f); if (locale == null) { locale = getResources().getConfiguration().locale; } tabsContainer = new LinearLayout(context); tabsContainer.setOrientation(LinearLayout.HORIZONTAL); LayoutParams params = new LayoutParams(LayoutParams.MATCH_PARENT, LayoutParams.MATCH_PARENT); params.bottomMargin = underlineHeight; tabsContainer.setLayoutParams(params); addView(tabsContainer); } public void setViewPager(final ViewPager viewPager) { this.pager = viewPager; if (pager.getAdapter() == null) { throw new IllegalStateException("ViewPager does not have adapter instance."); } pager.setOnPageChangeListener(pageListener); getViewTreeObserver().addOnGlobalLayoutListener(new OnGlobalLayoutListener() { @SuppressWarnings("deprecation") @SuppressLint("NewApi") @Override public void onGlobalLayout() { if (Build.VERSION.SDK_INT < Build.VERSION_CODES.JELLY_BEAN) { getViewTreeObserver().removeGlobalOnLayoutListener(this); } else { getViewTreeObserver().removeOnGlobalLayoutListener(this); } currentPosition = pager.getCurrentItem(); currentPositionOffset = 0; scrollToChild(currentPosition, 0); } }); notifyDataSetChanged(); } public void setOnPageChangeListener(OnPageChangeListener listener) { this.delegatePageListener = listener; } public void setAllTabEnabled(boolean isEnabled) { for (int i = 0; i < tabsContainer.getChildCount(); ++i) { View tab = tabsContainer.getChildAt(i); tab.setEnabled(isEnabled); } } public void notifyDataSetChanged() { tabsContainer.removeAllViews(); tabCount = pager.getAdapter().getCount(); for (int i = 0; i < tabCount; i++) { if (pager.getAdapter() instanceof TabProvider) { addTab(i, ((TabProvider) pager.getAdapter()).getTab(i)); } else { Tab tab = new Tab(Integer.toString(i), pager.getAdapter().getPageTitle(i)); // TODO yangfan, id = ? addTab(i, tab); } } updateTabStyles(); selectTab(pager.getCurrentItem()); checkedTabWidths = false; } private void addTab(final int position, Tab tab) { View tabView = tab.buildTabView(getContext(), position, pager); tabsContainer.addView(tabView, position); } private void updateTabStyles() { for (int i = 0; i < tabCount; i++) { View v = tabsContainer.getChildAt(i); v.setLayoutParams(defaultTabLayoutParams); v.setBackgroundResource(tabBackgroundResId); v.setPadding(tabPadding, 0, tabPadding, 0); if (v instanceof TextView) { TextView tab = (TextView) v; tab.setTextSize(TypedValue.COMPLEX_UNIT_PX, tabTextSize); tab.setTypeface(tabTypeface, tabTypefaceStyle); if (tabTextColorStateList != null) { tab.setTextColor(tabTextColorStateList); } else { tab.setTextColor(tabTextColor); } // setAllCaps() is only available from API 14, so the upper case is made manually if we are // on a // pre-ICS-build if (textAllCaps) { if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.ICE_CREAM_SANDWICH) { tab.setAllCaps(true); } else { tab.setText(tab.getText().toString().toUpperCase(locale)); } } } } } @Override protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) { if (!shouldExpand || checkedTabWidths || MeasureSpec.getMode(widthMeasureSpec) == MeasureSpec.UNSPECIFIED) { super.onMeasure(widthMeasureSpec, heightMeasureSpec); return; } if (!checkedTabWidths) { // not measured yet super.onMeasure(widthMeasureSpec, heightMeasureSpec); } int myWidth = getMeasuredWidth(); int childWidth = 0; for (int i = 0; i < tabCount; i++) { childWidth += tabsContainer.getChildAt(i).getMeasuredWidth(); } if (childWidth > 0 && myWidth > 0) { scrollOffset = tabsContainer.getChildAt(0).getMeasuredWidth(); if (childWidth <= myWidth) { for (int i = 0; i < tabCount; i++) { View v = tabsContainer.getChildAt(i); v.setLayoutParams(expandedTabLayoutParams); v.setPadding(0, 0, 0, 0); } } checkedTabWidths = true; } super.onMeasure(widthMeasureSpec, heightMeasureSpec); } @Override protected void onConfigurationChanged(Configuration newConfig) { updateTabStyles(); checkedTabWidths = false; post(new Runnable() { @Override public void run() { scrollToChild(currentSelectedPosition, 0); } }); } private void scrollToChild(int position, int offset) { if (tabCount == 0) { return; } int newScrollX = tabsContainer.getChildAt(position).getLeft() + offset; if (position > 0 || offset > 0) { newScrollX -= scrollOffset; } if (newScrollX != lastScrollX) { lastScrollX = newScrollX; scrollTo(newScrollX, 0); } } private void selectTab(int position) { if (currentSelectedPosition == position) { return; } if (position >= tabCount || position < 0) { return; } View previousSelectedView = tabsContainer.getChildAt(currentSelectedPosition); if (previousSelectedView != null) { previousSelectedView.setSelected(false); } currentSelectedPosition = position; View currentSelectedView = tabsContainer.getChildAt(currentSelectedPosition); if (currentSelectedView != null) { currentSelectedView.setSelected(true); } } @Override protected void onDraw(Canvas canvas) { super.onDraw(canvas); if (isInEditMode() || tabCount == 0) { return; } final int height = getHeight(); // draw underline rectPaint.setColor(underlineColor); canvas.drawRect(0, height - underlineHeight, tabsContainer.getWidth(), height, rectPaint); // draw indicator line rectPaint.setColor(indicatorColor); // default: line below current tab View currentTab = tabsContainer.getChildAt(currentPosition); float lineLeft = currentTab.getLeft(); float lineRight = currentTab.getRight(); // if there is an offset, start interpolating left and right coordinates between current and // next tab if (currentPositionOffset > 0f && currentPosition < tabCount - 1) { View nextTab = tabsContainer.getChildAt(currentPosition + 1); final float nextTabLeft = nextTab.getLeft(); final float nextTabRight = nextTab.getRight(); lineLeft = (currentPositionOffset * nextTabLeft + (1f - currentPositionOffset) * lineLeft); lineRight = (currentPositionOffset * nextTabRight + (1f - currentPositionOffset) * lineRight); } canvas.drawRect(lineLeft, height - indicatorHeight, lineRight, height, rectPaint); // draw divider dividerPaint.setColor(dividerColor); for (int i = 0; i < tabCount - 1; i++) { View tab = tabsContainer.getChildAt(i); canvas.drawLine(tab.getRight(), dividerPadding, tab.getRight(), height - dividerPadding, dividerPaint); } } public void setIndicatorColorResource(int resId) { this.indicatorColor = getResources().getColor(resId); invalidate(); } public int getIndicatorColor() { return this.indicatorColor; } public void setIndicatorColor(int indicatorColor) { this.indicatorColor = indicatorColor; invalidate(); } public int getIndicatorHeight() { return indicatorHeight; } public void setIndicatorHeight(int indicatorLineHeightPx) { this.indicatorHeight = indicatorLineHeightPx; invalidate(); } public void setUnderlineColorResource(int resId) { this.underlineColor = getResources().getColor(resId); invalidate(); } public int getUnderlineColor() { return underlineColor; } public void setUnderlineColor(int underlineColor) { this.underlineColor = underlineColor; invalidate(); } public void setDividerColorResource(int resId) { this.dividerColor = getResources().getColor(resId); invalidate(); } public int getDividerColor() { return dividerColor; } public void setDividerColor(int dividerColor) { this.dividerColor = dividerColor; invalidate(); } public int getUnderlineHeight() { return underlineHeight; } public void setUnderlineHeight(int underlineHeightPx) { this.underlineHeight = underlineHeightPx; invalidate(); } public int getDividerPadding() { return dividerPadding; } public void setDividerPadding(int dividerPaddingPx) { this.dividerPadding = dividerPaddingPx; invalidate(); } public int getScrollOffset() { return scrollOffset; } public void setScrollOffset(int scrollOffsetPx) { this.scrollOffset = scrollOffsetPx; invalidate(); } public boolean getShouldExpand() { return shouldExpand; } public void setShouldExpand(boolean shouldExpand) { this.shouldExpand = shouldExpand; requestLayout(); } public boolean isTextAllCaps() { return textAllCaps; } public void setAllCaps(boolean textAllCaps) { this.textAllCaps = textAllCaps; } public int getTextSize() { return tabTextSize; } public void setTextSize(int textSizePx) { this.tabTextSize = textSizePx; updateTabStyles(); } public void setTextColorResource(int resId) { this.tabTextColor = getResources().getColor(resId); updateTabStyles(); } public int getTextColor() { return tabTextColor; } public void setTextColor(int textColor) { this.tabTextColor = textColor; updateTabStyles(); } public void setTypeface(Typeface typeface, int style) { this.tabTypeface = typeface; this.tabTypefaceStyle = style; updateTabStyles(); } public int getTabBackground() { return tabBackgroundResId; } public void setTabBackground(int resId) { this.tabBackgroundResId = resId; } public int getTabPaddingLeftRight() { return tabPadding; } public void setTabPaddingLeftRight(int paddingPx) { this.tabPadding = paddingPx; updateTabStyles(); } @Override public void onRestoreInstanceState(Parcelable state) { SavedState savedState = (SavedState) state; super.onRestoreInstanceState(savedState.getSuperState()); currentPosition = savedState.currentPosition; requestLayout(); } @Override public Parcelable onSaveInstanceState() { Parcelable superState = super.onSaveInstanceState(); SavedState savedState = new SavedState(superState); savedState.currentPosition = currentPosition; return savedState; } public interface TabProvider { Tab getTab(int position); Tab getTab(String id); int getTabPositionById(String id); String getTabIdByPosition(int position); } static class SavedState extends BaseSavedState { public static final Creator<SavedState> CREATOR = new Creator<SavedState>() { @Override public SavedState createFromParcel(Parcel in) { return new SavedState(in); } @Override public SavedState[] newArray(int size) { return new SavedState[size]; } }; int currentPosition; public SavedState(Parcelable superState) { super(superState); } private SavedState(Parcel in) { super(in); currentPosition = in.readInt(); } @Override public void writeToParcel(Parcel dest, int flags) { super.writeToParcel(dest, flags); dest.writeInt(currentPosition); } } public static class Tab { private CharSequence text; private View customView; private View tabView; private int position; /** * Tab id, used for navigation. */ private String id; public Tab(String id) { this.id = id; } public Tab(String id, CharSequence text) { this(id); this.text = text; } public Tab(String id, View customView) { this(id); this.customView = customView; } public CharSequence getText() { return text; } public void setText(CharSequence text) { this.text = text; if (tabView instanceof TextView) { ((TextView) tabView).setText(text); } } public View getCustomView() { return customView; } public View getTabView() { return tabView; } public int getPosition() { return position; } public View buildTabView(Context context, final int position, final ViewPager pager) { this.position = position; if (customView != null) { tabView = customView; } else { tabView = new TextView(context); TextView textTabView = (TextView) tabView; textTabView.setText(text); textTabView.setFocusable(true); textTabView.setGravity(Gravity.CENTER); textTabView.setSingleLine(); } tabView.setOnClickListener(new OnClickListener() { @Override public void onClick(View v) { pager.setCurrentItem(position); } }); return tabView; } public String getId() { return id; } } private class PageListener implements OnPageChangeListener { @Override public void onPageScrolled(int position, float positionOffset, int positionOffsetPixels) { if (position >= tabsContainer.getChildCount()) { return; } currentPosition = position; currentPositionOffset = positionOffset; scrollToChild(position, (int) (positionOffset * tabsContainer.getChildAt(position).getWidth())); invalidate(); if (delegatePageListener != null) { delegatePageListener.onPageScrolled(position, positionOffset, positionOffsetPixels); } } @Override public void onPageScrollStateChanged(int state) { if (state == ViewPager.SCROLL_STATE_IDLE) { scrollToChild(pager.getCurrentItem(), 0); } if (delegatePageListener != null) { delegatePageListener.onPageScrollStateChanged(state); } } @Override public void onPageSelected(int position) { if (pager.getAdapter().getCount() <= position) { return; } selectTab(position); invalidate(); if (delegatePageListener != null) { delegatePageListener.onPageSelected(position); } } } }