Java tutorial
/* * Copyright (C) 2015 Basil Miller * * 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.wl.tabguidance.utils; import android.animation.Animator; import android.animation.AnimatorListenerAdapter; import android.animation.ArgbEvaluator; import android.animation.ValueAnimator; import android.annotation.SuppressLint; import android.content.Context; import android.content.res.Configuration; import android.content.res.TypedArray; import android.graphics.Canvas; import android.graphics.Color; import android.graphics.Paint; import android.graphics.Rect; import android.graphics.RectF; import android.graphics.Typeface; import android.os.Parcel; import android.os.Parcelable; import android.support.v4.view.ViewCompat; import android.support.v4.view.ViewPager; import android.text.TextPaint; import android.text.TextUtils; import android.util.AttributeSet; import android.view.MotionEvent; import android.view.View; import android.view.animation.AccelerateDecelerateInterpolator; import android.view.animation.Interpolator; import android.view.animation.LinearInterpolator; import android.widget.Scroller; import com.wl.tabguidance.R; import java.lang.reflect.Field; import java.util.Arrays; import java.util.Random; /** * Created by GIGAMOLE on 24.03.2016. * Note: * ? tabTitle ??view */ @SuppressWarnings("unused") public class TabLayoutTitleStrip extends View implements ViewPager.OnPageChangeListener { // NTS constants private final static int HIGH_QUALITY_FLAGS = Paint.ANTI_ALIAS_FLAG | Paint.DITHER_FLAG; private final static String PREVIEW_TITLE = "Title"; private final static int INVALID_INDEX = -1; // Default variables private final static int DEFAULT_ANIMATION_DURATION = 350; private final static float DEFAULT_STRIP_FACTOR = 2.5F; private final static float DEFAULT_STRIP_WEIGHT = 10.0F; private final static float DEFAULT_CORNER_RADIUS = 5.0F; private final static int DEFAULT_INACTIVE_COLOR = Color.GRAY; private final static int DEFAULT_ACTIVE_COLOR = Color.WHITE; private final static int DEFAULT_STRIP_COLOR = Color.RED; private final static int DEFAULT_TITLE_SIZE = 0; // Title size offer to view height private final static float TITLE_SIZE_FRACTION = 0.35F; // Max and min fraction private final static float MIN_FRACTION = 0.0F; private final static float MAX_FRACTION = 1.0F; // NTS and strip bounds private final RectF mBounds = new RectF(); private final RectF mStripBounds = new RectF(); private final Rect mTitleBounds = new Rect(); // Main paint private final Paint mStripPaint = new Paint(HIGH_QUALITY_FLAGS) { { setStyle(Style.FILL); } }; // Paint for tav title private final Paint mTitlePaint = new TextPaint(HIGH_QUALITY_FLAGS) { { setTextAlign(Align.CENTER); } }; // Variables for animator private final ValueAnimator mAnimator = new ValueAnimator(); private final ArgbEvaluator mColorEvaluator = new ArgbEvaluator(); private final ResizeInterpolator mResizeInterpolator = new ResizeInterpolator(); private int mAnimationDuration; // NTS titles private String[] mTitles; // Variables for ViewPager private ViewPager mViewPager; private ViewPager.OnPageChangeListener mOnPageChangeListener; private int mScrollState; // Tab listener private OnTabStripSelectedIndexListener mOnTabStripSelectedIndexListener; private ValueAnimator.AnimatorListener mAnimatorListener; // Variables for sizes private float mTabSize; // Tab title size and margin private float mTitleSize; // Strip type and gravity private StripType mStripType; private StripGravity mStripGravity; // Corners radius for rect mode private float mStripWeight; private float mCornersRadius; // Indexes private int mLastIndex = INVALID_INDEX; private int mIndex = INVALID_INDEX; // General fraction value private float mFraction; // Coordinates of strip private float mStartStripX; private float mEndStripX; private float mStripLeft; private float mStripRight; // Detect if is bar mode or indicator pager mode private boolean mIsViewPagerMode; // Detect if we move from left to right private boolean mIsResizeIn; // Detect if we get action down event private boolean mIsActionDown; // Detect if we get action down event on strip private boolean mIsTabActionDown; // Detect when we set index from tab bar nor from ViewPager private boolean mIsSetIndexFromTabBar; // Color variables private int mInactiveColor; private int mActiveColor; // Custom typeface private Typeface mTypeface; public TabLayoutTitleStrip(final Context context) { this(context, null); } public TabLayoutTitleStrip(final Context context, final AttributeSet attrs) { this(context, attrs, 0); } public TabLayoutTitleStrip(final Context context, final AttributeSet attrs, final int defStyleAttr) { super(context, attrs, defStyleAttr); //Init NTS // Always draw setWillNotDraw(false); // Speed and fix for pre 17 API ViewCompat.setLayerType(this, ViewCompat.LAYER_TYPE_SOFTWARE, null); setLayerType(LAYER_TYPE_SOFTWARE, null); final TypedArray typedArray = context.obtainStyledAttributes(attrs, R.styleable.TabTitleStrip); try { setStripColor(typedArray.getColor(R.styleable.TabTitleStrip_nts_color, DEFAULT_STRIP_COLOR)); setTitleSize(typedArray.getDimension(R.styleable.TabTitleStrip_nts_size, DEFAULT_TITLE_SIZE)); setStripWeight(typedArray.getDimension(R.styleable.TabTitleStrip_nts_weight, DEFAULT_STRIP_WEIGHT)); setStripFactor(typedArray.getFloat(R.styleable.TabTitleStrip_nts_factor, DEFAULT_STRIP_FACTOR)); setStripType(typedArray.getInt(R.styleable.TabTitleStrip_nts_type, StripType.LINE_INDEX)); setStripGravity(typedArray.getInt(R.styleable.TabTitleStrip_nts_gravity, StripGravity.BOTTOM_INDEX)); setTypeface(typedArray.getString(R.styleable.TabTitleStrip_nts_typeface)); setInactiveColor( typedArray.getColor(R.styleable.TabTitleStrip_nts_inactive_color, DEFAULT_INACTIVE_COLOR)); setActiveColor(typedArray.getColor(R.styleable.TabTitleStrip_nts_active_color, DEFAULT_ACTIVE_COLOR)); setAnimationDuration(typedArray.getInteger(R.styleable.TabTitleStrip_nts_animation_duration, DEFAULT_ANIMATION_DURATION)); setCornersRadius( typedArray.getDimension(R.styleable.TabTitleStrip_nts_corners_radius, DEFAULT_CORNER_RADIUS)); // Get titles String[] titles = null; try { final int titlesResId = typedArray.getResourceId(R.styleable.TabTitleStrip_nts_titles, 0); titles = titlesResId == 0 ? null : typedArray.getResources().getStringArray(titlesResId); } catch (Exception exception) { titles = null; exception.printStackTrace(); } finally { if (titles == null) { if (isInEditMode()) { titles = new String[new Random().nextInt(5) + 1]; Arrays.fill(titles, PREVIEW_TITLE); } else titles = new String[0]; } setTitles(titles); } // Init animator mAnimator.setFloatValues(MIN_FRACTION, MAX_FRACTION); mAnimator.setInterpolator(new LinearInterpolator()); mAnimator.addUpdateListener(new ValueAnimator.AnimatorUpdateListener() { @Override public void onAnimationUpdate(final ValueAnimator animation) { updateIndicatorPosition((Float) animation.getAnimatedValue()); } }); } finally { typedArray.recycle(); } } public int getAnimationDuration() { return mAnimationDuration; } public void setAnimationDuration(final int animationDuration) { mAnimationDuration = animationDuration; mAnimator.setDuration(mAnimationDuration); resetScroller(); } public String[] getTitles() { return mTitles; } public void setTitles(final int... titleResIds) { final String[] titles = new String[titleResIds.length]; for (int i = 0; i < titleResIds.length; i++) titles[i] = getResources().getString(titleResIds[i]); setTitles(titles); } public void setTitles(final String... titles) { for (int i = 0; i < titles.length; i++) titles[i] = titles[i].toUpperCase(); mTitles = titles; requestLayout(); } public int getStripColor() { return mStripPaint.getColor(); } public void setStripColor(final int color) { mStripPaint.setColor(color); postInvalidate(); } public void setStripWeight(final float stripWeight) { mStripWeight = stripWeight; requestLayout(); } public StripGravity getStripGravity() { return mStripGravity; } private void setStripGravity(final int index) { switch (index) { case StripGravity.TOP_INDEX: setStripGravity(StripGravity.TOP); break; case StripGravity.BOTTOM_INDEX: default: setStripGravity(StripGravity.BOTTOM); break; } } public void setStripGravity(final StripGravity stripGravity) { mStripGravity = stripGravity; requestLayout(); } public StripType getStripType() { return mStripType; } private void setStripType(final int index) { switch (index) { case StripType.POINT_INDEX: setStripType(StripType.POINT); break; case StripType.LINE_INDEX: default: setStripType(StripType.LINE); break; } } public void setStripType(final StripType stripType) { mStripType = stripType; requestLayout(); } public float getStripFactor() { return mResizeInterpolator.getFactor(); } public void setStripFactor(final float factor) { mResizeInterpolator.setFactor(factor); } public Typeface getTypeface() { return mTypeface; } public void setTypeface(final String typeface) { if (TextUtils.isEmpty(typeface)) return; Typeface tempTypeface; try { tempTypeface = Typeface.createFromAsset(getContext().getAssets(), typeface); } catch (Exception e) { tempTypeface = Typeface.create(Typeface.DEFAULT, Typeface.NORMAL); e.printStackTrace(); } setTypeface(tempTypeface); } public void setTypeface(final Typeface typeface) { mTypeface = typeface; mTitlePaint.setTypeface(typeface); postInvalidate(); } public int getActiveColor() { return mActiveColor; } public void setActiveColor(final int activeColor) { mActiveColor = activeColor; postInvalidate(); } public int getInactiveColor() { return mInactiveColor; } public void setInactiveColor(final int inactiveColor) { mInactiveColor = inactiveColor; postInvalidate(); } public float getCornersRadius() { return mCornersRadius; } public void setCornersRadius(final float cornersRadius) { mCornersRadius = cornersRadius; postInvalidate(); } public float getTitleSize() { return mTitleSize; } public void setTitleSize(final float titleSize) { mTitleSize = titleSize; mTitlePaint.setTextSize(titleSize); postInvalidate(); } public OnTabStripSelectedIndexListener getOnTabStripSelectedIndexListener() { return mOnTabStripSelectedIndexListener; } // Set on tab bar selected index listener where you can trigger action onStart or onEnd public void setOnTabStripSelectedIndexListener( final OnTabStripSelectedIndexListener onTabStripSelectedIndexListener) { mOnTabStripSelectedIndexListener = onTabStripSelectedIndexListener; if (mAnimatorListener == null) mAnimatorListener = new AnimatorListenerAdapter() { @Override public void onAnimationStart(final Animator animation) { if (mOnTabStripSelectedIndexListener != null) mOnTabStripSelectedIndexListener.onStartTabSelected(mTitles[mIndex], mIndex); animation.removeListener(this); animation.addListener(this); } @Override public void onAnimationEnd(final Animator animation) { if (mIsViewPagerMode) return; animation.removeListener(this); animation.addListener(this); if (mOnTabStripSelectedIndexListener != null) mOnTabStripSelectedIndexListener.onEndTabSelected(mTitles[mIndex], mIndex); } }; mAnimator.removeListener(mAnimatorListener); mAnimator.addListener(mAnimatorListener); } public void setViewPager(final ViewPager viewPager) { // Detect whether ViewPager mode if (viewPager == null) { mIsViewPagerMode = false; return; } if (viewPager.equals(mViewPager)) return; if (mViewPager != null) //noinspection deprecation mViewPager.setOnPageChangeListener(null); if (viewPager.getAdapter() == null) throw new IllegalStateException("ViewPager does not provide adapter instance."); mIsViewPagerMode = true; mViewPager = viewPager; mViewPager.addOnPageChangeListener(this); resetScroller(); postInvalidate(); } public void setViewPager(final ViewPager viewPager, int index) { setViewPager(viewPager); mIndex = index; if (mIsViewPagerMode) mViewPager.setCurrentItem(index, true); postInvalidate(); } // Reset scroller and reset scroll duration equals to animation duration private void resetScroller() { if (mViewPager == null) return; try { final Field scrollerField = ViewPager.class.getDeclaredField("mScroller"); scrollerField.setAccessible(true); final ResizeViewPagerScroller scroller = new ResizeViewPagerScroller(getContext()); scrollerField.set(mViewPager, scroller); } catch (Exception e) { e.printStackTrace(); } } public void setOnPageChangeListener(final ViewPager.OnPageChangeListener listener) { mOnPageChangeListener = listener; } public int getTabIndex() { return mIndex; } public void setTabIndex(int index) { setTabIndex(index, false); } // Set tab index from touch or programmatically public void setTabIndex(int tabIndex, boolean isForce) { if (mAnimator.isRunning()) return; if (mTitles.length == 0) return; int index = tabIndex; boolean force = isForce; // This check gives us opportunity to have an non selected tab if (mIndex == INVALID_INDEX) force = true; // Detect if last is the same if (index == mIndex) return; // Snap index to tabs size index = Math.max(0, Math.min(index, mTitles.length - 1)); mIsResizeIn = index < mIndex; mLastIndex = mIndex; mIndex = index; mIsSetIndexFromTabBar = true; if (mIsViewPagerMode) { if (mViewPager == null) throw new IllegalStateException("ViewPager is null."); mViewPager.setCurrentItem(index, !force); } // Set startX and endX for animation, where we animate two sides of rect with different interpolation mStartStripX = mStripLeft; mEndStripX = (mIndex * mTabSize) + (mStripType == StripType.POINT ? mTabSize * 0.5F : 0.0F); /// If it force, so update immediately, else animate // This happens if we set index onCreate or something like this // You can use force param or call this method in some post() if (force) { updateIndicatorPosition(MAX_FRACTION); // Force onPageScrolled listener and refresh VP if (mIsViewPagerMode) { if (!mViewPager.isFakeDragging()) mViewPager.beginFakeDrag(); if (mViewPager.isFakeDragging()) { mViewPager.fakeDragBy(0.0F); mViewPager.endFakeDrag(); } } } else mAnimator.start(); } // Deselect active index and reset pointer public void deselect() { mLastIndex = INVALID_INDEX; mIndex = INVALID_INDEX; mStartStripX = INVALID_INDEX * mTabSize; mEndStripX = mStartStripX; updateIndicatorPosition(MIN_FRACTION); } private void updateIndicatorPosition(final float fraction) { // Update general fraction mFraction = fraction; // Set the strip left side coordinate mStripLeft = mStartStripX + (mResizeInterpolator.getResizeInterpolation(fraction, mIsResizeIn) * (mEndStripX - mStartStripX)); // Set the strip right side coordinate mStripRight = (mStartStripX + (mStripType == StripType.LINE ? mTabSize : mStripWeight)) + (mResizeInterpolator.getResizeInterpolation(fraction, !mIsResizeIn) * (mEndStripX - mStartStripX)); // Update NTS postInvalidate(); } // Update NTS private void notifyDataSetChanged() { requestLayout(); postInvalidate(); } @Override public boolean onTouchEvent(final MotionEvent event) { // Return if animation is running if (mAnimator.isRunning()) return true; // If is not idle state, return if (mScrollState != ViewPager.SCROLL_STATE_IDLE) return true; switch (event.getAction()) { case MotionEvent.ACTION_DOWN: // Action down touch mIsActionDown = true; if (!mIsViewPagerMode) break; // Detect if we touch down on tab, later to move mIsTabActionDown = (int) (event.getX() / mTabSize) == mIndex; break; case MotionEvent.ACTION_MOVE: // If tab touched, so move if (mIsTabActionDown) { mViewPager.setCurrentItem((int) (event.getX() / mTabSize), true); break; } if (mIsActionDown) break; case MotionEvent.ACTION_UP: // Press up and set tab index relative to current coordinate if (mIsActionDown) setTabIndex((int) (event.getX() / mTabSize)); case MotionEvent.ACTION_CANCEL: case MotionEvent.ACTION_OUTSIDE: default: // Reset action touch variables mIsTabActionDown = false; mIsActionDown = false; break; } return true; } @SuppressLint("DrawAllocation") @Override protected void onMeasure(final int widthMeasureSpec, final int heightMeasureSpec) { super.onMeasure(widthMeasureSpec, heightMeasureSpec); // Get measure size final float width = MeasureSpec.getSize(widthMeasureSpec); final float height = MeasureSpec.getSize(heightMeasureSpec); // Set bounds for NTS mBounds.set(0.0F, 0.0F, width, height); if (mTitles.length == 0 || width == 0 || height == 0) return; // Get smaller side mTabSize = width / (float) mTitles.length; if ((int) mTitleSize == DEFAULT_TITLE_SIZE) setTitleSize((height - mStripWeight) * TITLE_SIZE_FRACTION); // Set start position of strip for preview or on start if (isInEditMode() || !mIsViewPagerMode) { mIsSetIndexFromTabBar = true; // Set random in preview mode if (isInEditMode()) mIndex = new Random().nextInt(mTitles.length); mStartStripX = (mIndex * mTabSize) + (mStripType == StripType.POINT ? mTabSize * 0.5F : 0.0F); mEndStripX = mStartStripX; updateIndicatorPosition(MAX_FRACTION); } } @Override protected void onDraw(final Canvas canvas) { // Set bound of strip mStripBounds.set(mStripLeft - (mStripType == StripType.POINT ? mStripWeight * 0.5F : 0.0F), mStripGravity == StripGravity.BOTTOM ? mBounds.height() - mStripWeight : 0.0F, mStripRight - (mStripType == StripType.POINT ? mStripWeight * 0.5F : 0.0F), mStripGravity == StripGravity.BOTTOM ? mBounds.height() : mStripWeight); // Draw strip if (mCornersRadius == 0) canvas.drawRect(mStripBounds, mStripPaint); else canvas.drawRoundRect(mStripBounds, mCornersRadius, mCornersRadius, mStripPaint); // Draw tab titles for (int i = 0; i < mTitles.length; i++) { final String title = mTitles[i]; final float leftTitleOffset = (mTabSize * i) + (mTabSize * 0.5F); mTitlePaint.getTextBounds(title, 0, title.length(), mTitleBounds); final float topTitleOffset = (mBounds.height() - mStripWeight) * 0.5F + mTitleBounds.height() * 0.5F - mTitleBounds.bottom; // Get interpolated fraction for left last and current tab final float interpolation = mResizeInterpolator.getResizeInterpolation(mFraction, true); final float lastInterpolation = mResizeInterpolator.getResizeInterpolation(mFraction, false); // Check if we handle tab from touch on NTS or from ViewPager // There is a strange logic of ViewPager onPageScrolled method, so it is if (mIsSetIndexFromTabBar) { if (mIndex == i) updateCurrentTitle(interpolation); else if (mLastIndex == i) updateLastTitle(lastInterpolation); else updateInactiveTitle(); } else { if (i != mIndex && i != mIndex + 1) updateInactiveTitle(); else if (i == mIndex + 1) updateCurrentTitle(interpolation); else if (i == mIndex) updateLastTitle(lastInterpolation); } canvas.drawText(title, leftTitleOffset, topTitleOffset + (mStripGravity == StripGravity.TOP ? mStripWeight : 0.0F), mTitlePaint); } } // Method to transform current fraction of NTS and position private void updateCurrentTitle(final float interpolation) { mTitlePaint.setColor((int) mColorEvaluator.evaluate(interpolation, mInactiveColor, mActiveColor)); } // Method to transform last fraction of NTS and position private void updateLastTitle(final float lastInterpolation) { mTitlePaint.setColor((int) mColorEvaluator.evaluate(lastInterpolation, mActiveColor, mInactiveColor)); } // Method to transform others fraction of NTS and position private void updateInactiveTitle() { mTitlePaint.setColor(mInactiveColor); } @Override public void onPageScrolled(int position, float positionOffset, final int positionOffsetPixels) { if (mOnPageChangeListener != null) mOnPageChangeListener.onPageScrolled(position, positionOffset, positionOffsetPixels); // If we animate, don`t call this if (!mIsSetIndexFromTabBar) { mIsResizeIn = position < mIndex; mLastIndex = mIndex; mIndex = position; mStartStripX = (position * mTabSize) + (mStripType == StripType.POINT ? mTabSize * 0.5F : 0.0F); mEndStripX = mStartStripX + mTabSize; updateIndicatorPosition(positionOffset); } // Stop scrolling on animation end and reset values if (!mAnimator.isRunning() && mIsSetIndexFromTabBar) { mFraction = MIN_FRACTION; mIsSetIndexFromTabBar = false; } } @Override public void onPageSelected(final int position) { // This method is empty, because we call onPageSelected() when scroll state is idle } @Override public void onPageScrollStateChanged(final int state) { // If VP idle, reset to MIN_FRACTION mScrollState = state; if (state == ViewPager.SCROLL_STATE_IDLE) { if (mOnPageChangeListener != null) mOnPageChangeListener.onPageSelected(mIndex); if (mIsViewPagerMode && mOnTabStripSelectedIndexListener != null) mOnTabStripSelectedIndexListener.onEndTabSelected(mTitles[mIndex], mIndex); } if (mOnPageChangeListener != null) mOnPageChangeListener.onPageScrollStateChanged(state); } @Override public void onRestoreInstanceState(Parcelable state) { final SavedState savedState = (SavedState) state; super.onRestoreInstanceState(savedState.getSuperState()); mIndex = savedState.index; requestLayout(); } @Override public Parcelable onSaveInstanceState() { final Parcelable superState = super.onSaveInstanceState(); final SavedState savedState = new SavedState(superState); savedState.index = mIndex; return savedState; } // Save current index instance private static class SavedState extends BaseSavedState { private int index; public SavedState(Parcelable superState) { super(superState); } private SavedState(Parcel in) { super(in); index = in.readInt(); } @Override public void writeToParcel(Parcel dest, int flags) { super.writeToParcel(dest, flags); dest.writeInt(index); } @SuppressWarnings("UnusedDeclaration") 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]; } }; } @Override protected void onConfigurationChanged(final Configuration newConfig) { // Config view on rotate etc. super.onConfigurationChanged(newConfig); requestLayout(); // Refresh strip and state after config changed to current final int tempIndex = mIndex; deselect(); post(new Runnable() { @Override public void run() { setTabIndex(tempIndex, true); } }); } // Custom scroller with custom scroll duration private class ResizeViewPagerScroller extends Scroller { public ResizeViewPagerScroller(Context context) { super(context, new AccelerateDecelerateInterpolator()); } @Override public void startScroll(int startX, int startY, int dx, int dy, int duration) { super.startScroll(startX, startY, dx, dy, mAnimationDuration); } @Override public void startScroll(int startX, int startY, int dx, int dy) { super.startScroll(startX, startY, dx, dy, mAnimationDuration); } } // Resize interpolator to create smooth effect on strip according to inspiration design // This is like improved accelerated and decelerated interpolator private static class ResizeInterpolator implements Interpolator { // Spring factor private float mFactor; // Check whether side we move private boolean mResizeIn; public float getFactor() { return mFactor; } public void setFactor(final float factor) { mFactor = factor; } @Override public float getInterpolation(final float input) { if (mResizeIn) return (float) (1.0F - Math.pow((1.0F - input), 2.0F * mFactor)); else return (float) (Math.pow(input, 2.0F * mFactor)); } public float getResizeInterpolation(final float input, final boolean resizeIn) { mResizeIn = resizeIn; return getInterpolation(input); } } // NTS strip type public enum StripType { LINE, POINT; private final static int LINE_INDEX = 0; private final static int POINT_INDEX = 1; } // NTS strip gravity public enum StripGravity { BOTTOM, TOP; private final static int BOTTOM_INDEX = 0; private final static int TOP_INDEX = 1; } // Out listener for selected index public interface OnTabStripSelectedIndexListener { void onStartTabSelected(final String title, final int index); void onEndTabSelected(final String title, final int index); } }