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.astuetz; import android.annotation.SuppressLint; import android.content.Context; import android.content.res.ColorStateList; import android.content.res.TypedArray; import android.graphics.Canvas; import android.graphics.Color; 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.ViewGroup; import android.view.ViewTreeObserver.OnGlobalLayoutListener; import android.widget.HorizontalScrollView; import android.widget.ImageButton; import android.widget.LinearLayout; import android.widget.TextView; import java.util.Locale; import com.astuetz.pagerslidingtabstrip.R; public class PagerSlidingTabStripPlus extends HorizontalScrollView { // ****************** ICON INTERFACE ******************* \\ public interface IconTabProvider { public int getPageIconResId(int position); } // @formatter:off private static final int[] ATTRS = new int[] { android.R.attr.textSize, android.R.attr.textColor }; // @formatter:on // ****************** LAYOUTS PARAMS DECLARATIONS ******************* \\ private LinearLayout.LayoutParams defaultTabLayoutParams; private LinearLayout.LayoutParams expandedTabLayoutParams; // ****************** LISTENERS DECLARATIONS ******************* \\ private final PageListener pageListener = new PageListener(); public OnPageChangeListener delegatePageListener; // ****************** LAYOUTS DECLARATIONS ******************* \\ private LinearLayout tabsContainer; private ViewPager pager; // ****************** POSITION VALUES ******************* \\ private int currentPosition = 0; private float currentPositionOffset = 0f; // ****************** PAINT VARIABLES ******************* \\ private Paint rectPaint; private Paint dividerPaint; // ****************** COLORS DECLARATIONS ******************* \\ private int indicatorColor = 0xFF666666; private int underlineColor = 0x1A000000; private int dividerColor = 0x1A000000; private ColorStateList textColorTab; // ****************** BOOLEANS DECLARATIONS ******************* \\ private boolean shouldExpand = false; private boolean textAllCaps = true; private boolean hasDivider = true; // ****************** GENERAL INTEGER DECLARATIONS ******************* \\ private int scrollOffset = 52; private int indicatorHeight = 8; private int underlineHeight = 2; private int dividerPadding = 12; private int tabPaddingLeft = 24; private int tabPaddingRight = 24; private int tabPaddingTop = 0; private int tabPaddingBottom = 0; private int dividerWidth = 1; private int indicatorAlpha = 255; private int tabCount; private int lastScrollX = 0; private int tabsGravity = Gravity.CENTER; // ****************** TEXT VALUES DECLARATIONS ******************* \\ private int tabTextSize = 12; private int tabTextColor = 0xFF666666; private Typeface tabTypeface = null; private int tabTypefaceStyle = Typeface.BOLD; private int tabBackgroundResId = R.drawable.background_tab; private Locale locale; // ****************** CONSTRUCTORS ******************* \\ public PagerSlidingTabStripPlus(Context context) { this(context, null); } public Typeface getTabTypeface() { return tabTypeface; } public void setTabTypeface(Typeface tabTypeface) { this.tabTypeface = tabTypeface; } public int getTabTypefaceStyle() { return tabTypefaceStyle; } public void setTabTypefaceStyle(int tabTypefaceStyle) { this.tabTypefaceStyle = tabTypefaceStyle; } public int getTabTextSize() { return tabTextSize; } public void setTabTextSize(int tabTextSize) { this.tabTextSize = tabTextSize; } public PagerSlidingTabStripPlus(Context context, AttributeSet attrs) { this(context, attrs, 0); } public PagerSlidingTabStripPlus(Context context, AttributeSet attrs, int defStyle) { super(context, attrs, defStyle); setFillViewport(true); // ScrollView stretch his content height to fill his viewport setWillNotDraw(false); // Layout parameters tabsContainer = new LinearLayout(context); tabsContainer.setOrientation(LinearLayout.HORIZONTAL); tabsContainer.setLayoutParams(new LayoutParams(LayoutParams.MATCH_PARENT, LayoutParams.MATCH_PARENT)); addView(tabsContainer); DisplayMetrics dm = getResources().getDisplayMetrics(); // Converting values to floating point value 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); tabPaddingLeft = (int) TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_DIP, tabPaddingLeft, dm); tabPaddingRight = (int) TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_DIP, tabPaddingRight, dm); tabPaddingTop = (int) TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_DIP, tabPaddingTop, dm); tabPaddingBottom = (int) TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_DIP, tabPaddingBottom, 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.PagerSlidingTabStripPlus); indicatorColor = a.getColor(R.styleable.PagerSlidingTabStripPlus_pstsIndicatorColor, indicatorColor); underlineColor = a.getColor(R.styleable.PagerSlidingTabStripPlus_pstsUnderlineColor, underlineColor); dividerColor = a.getColor(R.styleable.PagerSlidingTabStripPlus_pstsDividerColor, dividerColor); indicatorHeight = a.getDimensionPixelSize(R.styleable.PagerSlidingTabStripPlus_pstsIndicatorHeight, indicatorHeight); underlineHeight = a.getDimensionPixelSize(R.styleable.PagerSlidingTabStripPlus_pstsUnderlineHeight, underlineHeight); dividerPadding = a.getDimensionPixelSize(R.styleable.PagerSlidingTabStripPlus_pstsDividerPadding, dividerPadding); tabPaddingLeft = a.getDimensionPixelSize(R.styleable.PagerSlidingTabStripPlus_pstsTabPaddingLeft, tabPaddingLeft); tabPaddingRight = a.getDimensionPixelOffset(R.styleable.PagerSlidingTabStripPlus_pstsTabPaddingRight, tabPaddingRight); tabPaddingTop = a.getDimensionPixelOffset(R.styleable.PagerSlidingTabStripPlus_pstsTabPaddingTop, tabPaddingTop); tabPaddingBottom = a.getDimensionPixelOffset(R.styleable.PagerSlidingTabStripPlus_pstsTabPaddingBottom, tabPaddingBottom); tabBackgroundResId = a.getResourceId(R.styleable.PagerSlidingTabStripPlus_pstsTabBackground, tabBackgroundResId); shouldExpand = a.getBoolean(R.styleable.PagerSlidingTabStripPlus_pstsShouldExpand, shouldExpand); scrollOffset = a.getDimensionPixelSize(R.styleable.PagerSlidingTabStripPlus_pstsScrollOffset, scrollOffset); textAllCaps = a.getBoolean(R.styleable.PagerSlidingTabStripPlus_pstsTextAllCaps, textAllCaps); textColorTab = a.getColorStateList(R.styleable.PagerSlidingTabStripPlus_pstsTextColorTab); indicatorAlpha = a.getInteger(R.styleable.PagerSlidingTabStripPlus_pstsIndicatorAlpha, indicatorAlpha); hasDivider = a.getBoolean(R.styleable.PagerSlidingTabStripPlus_pstsHasDivider, hasDivider); tabTextSize = a.getDimensionPixelSize(R.styleable.PagerSlidingTabStripPlus_pstsTabTextSize, tabTextSize); tabsGravity = a.getInteger(R.styleable.PagerSlidingTabStripPlus_pstsTabsTitleGravity, tabsGravity); 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; } } /*** * Set the view pager that we want to relate * * set the pageListener and refresh the content if there are changes * * @param pager */ public void setViewPager(ViewPager pager) { this.pager = pager; if (pager.getAdapter() == null) { throw new IllegalStateException("ViewPager does not have adapter instance."); } pager.setOnPageChangeListener(pageListener); notifyDataSetChanged(); } /** * Assign the page listener of the adapter if we want * * @param listener */ public void setOnPageChangeListener(OnPageChangeListener listener) { this.delegatePageListener = listener; } public void notifyDataSetChanged() { tabsContainer.removeAllViews(); tabCount = pager.getAdapter().getCount(); // creates the tabs using page titles in the adapter for (int i = 0; i < tabCount; i++) { if (pager.getAdapter() instanceof IconTabProvider) { addIconTab(i, ((IconTabProvider) pager.getAdapter()).getPageIconResId(i)); } else { addTextTab(i, pager.getAdapter().getPageTitle(i).toString()); } } updateTabStyles(); 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(); tabsContainer.getChildAt(currentPosition).setSelected(true); scrollToChild(currentPosition, 0); } }); } private void addTextTab(final int position, String title) { TextView tab = new TextView(getContext()); tab.setText(title); tab.setGravity(tabsGravity); tab.setSingleLine(); addTab(position, tab); } private void addIconTab(final int position, int resId) { ImageButton tab = new ImageButton(getContext()); tab.setImageResource(resId); addTab(position, tab); } private void addTab(final int position, View tab) { tab.setFocusable(true); tab.setPadding(tabPaddingLeft, tabPaddingTop, tabPaddingRight, tabPaddingBottom); LinearLayout tabLayout = new LinearLayout(getContext()); tabLayout.setOrientation(LinearLayout.VERTICAL); tabLayout.setGravity(Gravity.CENTER); tabLayout.addView(tab, 0, defaultTabLayoutParams); tabLayout.setOnClickListener(new OnClickListener() { @Override public void onClick(View v) { pager.setCurrentItem(position); } }); tabsContainer.addView(tabLayout, position, shouldExpand ? expandedTabLayoutParams : defaultTabLayoutParams); } private void updateTabStyles() { for (int i = 0; i < tabCount; i++) { for (int k = 0; k < ((LinearLayout) tabsContainer.getChildAt(i)).getChildCount(); k++) { View v = ((LinearLayout) tabsContainer.getChildAt(i)).getChildAt(k); v.setBackgroundResource(tabBackgroundResId); if (v instanceof TextView) { TextView tab = (TextView) v; tab.setTextSize(TypedValue.COMPLEX_UNIT_PX, tabTextSize); tab.setTypeface(tabTypeface, tabTypefaceStyle); // Setting color of textView if (textColorTab != null) { tab.setTextColor(textColorTab); } else { tab.setTextColor(Color.BLACK); } // 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)); } } } } } } 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); } } @Override protected void onDraw(Canvas canvas) { super.onDraw(canvas); if (isInEditMode() || tabCount == 0) { return; } final int height = getHeight(); // 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); } // draw underline rectPaint.setColor(underlineColor); canvas.drawRect(0, height - underlineHeight, tabsContainer.getWidth(), height, rectPaint); // draw indicator line rectPaint.setColor(Color.argb(indicatorAlpha, Color.red(indicatorColor), Color.green(indicatorColor), Color.blue(indicatorColor))); canvas.drawRect(lineLeft, height - indicatorHeight, lineRight, height, rectPaint); // draw divider if (hasDivider) { 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); } } } private class PageListener implements OnPageChangeListener { @Override public void onPageScrolled(int position, float positionOffset, int positionOffsetPixels) { 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 (delegatePageListener != null) { delegatePageListener.onPageSelected(position); } tabsContainer.getChildAt(position).setSelected(true); for (int i = 0; i < tabsContainer.getChildCount(); i++) { if (i != position) { tabsContainer.getChildAt(i).setSelected(false); } } } } public TextView getCurrentTextViewTitleTabObject() { return (TextView) ((LinearLayout) tabsContainer.getChildAt(currentPosition)).getChildAt(0); } public TextView getTextViewTitleTabObjectAtPosition(int position) { return (TextView) ((LinearLayout) tabsContainer.getChildAt(position)).getChildAt(0); } public LinearLayout getCurrentSingleTabLayout() { return (LinearLayout) tabsContainer.getChildAt(currentPosition); } public LinearLayout getSingleTabLayoutAtPosition(int position) { return (LinearLayout) tabsContainer.getChildAt(position); } /** * Add new text view to the linear layout that contains the tab title* * @param position of the linear layout in the tabsContainer * @param text is the text of the subtitle */ public void addSubtitleAtTab(int position, String text) { LinearLayout tab = getSingleTabLayoutAtPosition(position); tab.setWeightSum(tab.getChildCount() + 1); if (tab.getChildCount() == 1) { tab.getChildAt(0).setLayoutParams(new LinearLayout.LayoutParams(LayoutParams.MATCH_PARENT, 0, 1)); } ((TextView) tab.getChildAt(0)).setGravity(Gravity.CENTER_HORIZONTAL); TextView newSubTab = new TextView(getContext()); newSubTab.setLayoutParams(new LinearLayout.LayoutParams(LayoutParams.MATCH_PARENT, 0, 1)); newSubTab.setText(text); newSubTab.setGravity(Gravity.CENTER_HORIZONTAL); tab.addView(newSubTab); updateTabStyles(); } public void setIndicatorColor(int indicatorColor) { this.indicatorColor = indicatorColor; invalidate(); } public void setIndicatorColorResource(int resId) { this.indicatorColor = getResources().getColor(resId); invalidate(); } public int getIndicatorColor() { return this.indicatorColor; } public void setIndicatorHeight(int indicatorLineHeightPx) { this.indicatorHeight = indicatorLineHeightPx; invalidate(); } public int getIndicatorHeight() { return indicatorHeight; } public void setUnderlineColor(int underlineColor) { this.underlineColor = underlineColor; invalidate(); } public void setUnderlineColorResource(int resId) { this.underlineColor = getResources().getColor(resId); invalidate(); } public int getUnderlineColor() { return underlineColor; } public void setDividerColor(int dividerColor) { this.dividerColor = dividerColor; invalidate(); } public void setDividerColorResource(int resId) { this.dividerColor = getResources().getColor(resId); invalidate(); } public int getDividerColor() { return dividerColor; } public void setUnderlineHeight(int underlineHeightPx) { this.underlineHeight = underlineHeightPx; invalidate(); } public int getUnderlineHeight() { return underlineHeight; } public void setDividerPadding(int dividerPaddingPx) { this.dividerPadding = dividerPaddingPx; invalidate(); } public int getDividerPadding() { return dividerPadding; } public void setScrollOffset(int scrollOffsetPx) { this.scrollOffset = scrollOffsetPx; invalidate(); } public int getScrollOffset() { return scrollOffset; } public void setShouldExpand(boolean shouldExpand) { this.shouldExpand = shouldExpand; requestLayout(); } public boolean getShouldExpand() { return shouldExpand; } public boolean isTextAllCaps() { return textAllCaps; } public void setAllCaps(boolean textAllCaps) { this.textAllCaps = textAllCaps; } public void setTextSize(int textSizePx) { this.tabTextSize = textSizePx; updateTabStyles(); } public int getTextSize() { return tabTextSize; } public void setTextColor(int textColor) { this.tabTextColor = textColor; updateTabStyles(); } public void setTextColorResource(int resId) { this.tabTextColor = getResources().getColor(resId); updateTabStyles(); } public int getTextColor() { return tabTextColor; } public void setTypeface(Typeface typeface, int style) { this.tabTypeface = typeface; this.tabTypefaceStyle = style; updateTabStyles(); } public void setTabBackground(int resId) { this.tabBackgroundResId = resId; } public int getTabBackground() { return tabBackgroundResId; } public void setTabPaddingLeftRight(int paddingPx) { this.tabPaddingLeft = paddingPx; updateTabStyles(); } public int getTabPaddingLeftRight() { return tabPaddingLeft; } @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; } static class SavedState extends BaseSavedState { 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 final Parcelable.Creator<SavedState> CREATOR = new Parcelable.Creator<SavedState>() { @Override public SavedState createFromParcel(Parcel in) { return new SavedState(in); } @Override public SavedState[] newArray(int size) { return new SavedState[size]; } }; } public boolean isHasDivider() { return hasDivider; } public void setHasDivider(boolean hasDivider) { this.hasDivider = hasDivider; } public float getIndicatorAlpha() { return indicatorAlpha; } public void setIndicatorAlpha(int indicatorAlpha) { this.indicatorAlpha = indicatorAlpha; } public int getCurrentPosition() { return currentPosition; } }