自定义控件之AndroidSegmentControlView,仿IOS平台UISegmentControlView,继承自View

Posted carbs_wang

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控件简介

UISegmentControl在ios平台的App中非常常见,其控件如下图所示:

      这种控件的主要作用是动态的更改界面的显示内容,一般应用于内容较多的界面,且分屏显示不同种类的内容。

      在android开发过程中,有时需要实现类似UISegmentControl的效果,这里我将自己的代码开源在github上了,命名为SegmentControlView,下面是实现的效果:




动态图片可点击如下链接:
https://github.com/Carbs0126/AndroidSegmentControlView

控件说明

SegmentControlView extends View

      这个SegmentControlView是继承自View的,而非组合控件,因此实现起来虽然有点繁琐,但是灵活性反而比组合控件要高很多,并且可以加上过度效果等,且比组合控件更加轻量化。

控件特点

      我实现的这个SegmentControlView具有如下特点:

1.SegmentControlView可设置与ViewPager联动,在segment切换时具有颜色渐变效果,类似微信。
2.可以自定义SegmentControlView的四个corner的半径。
3.自定义背景颜色与字体颜色、字体大小等等。
4.在xml中设置SegmentControlView中的多个titles,自动按照titles生成多个segment。
5.设置按下颜色与normal颜色的色值对比度。
6.具有AT_MOST的适配功能,即具有wrap_content模式
7.可以设置回调响应事件

使用方法

属性文件说明

<?xml version="1.0" encoding="utf-8"?>
<resources>

    <declare-styleable name="SegmentControlView">
        <attr name="scv_BackgroundSelectedColor" format="reference|color" />//选中segment的背景颜色
        <attr name="scv_BackgroundNormalColor" format="reference|color" />//未选中segment的背景颜色
        <attr name="scv_TextSelectedColor" format="reference|color" />//选中segment的文字颜色
        <attr name="scv_TextNormalColor" format="reference|color" />//未选中segment的文字颜色
        <attr name="scv_FrameColor" format="reference|color" />//segment边框的颜色
        <attr name="scv_FrameWidth" format="reference|dimension" />//segment边框的宽度
        <attr name="scv_FrameCornerRadius" format="reference|dimension" />//segment四个圆角的半径大小
        <attr name="scv_TextSize" format="reference|dimension" />//文字大小
        <attr name="scv_TextArray" format="reference" />//string数组,每一个string都会填充到一个segment中
        <attr name="scv_SelectedIndex" format="reference|integer" />//默认选中的segment
        <attr name="scv_SegmentPaddingHorizontal" format="reference|dimension" />//每一个segment内部的水平padding
        <attr name="scv_SegmentPaddingVertical" format="reference|dimension" />每一个Segment的竖直方向的padding
        <attr name="scv_Gradient" format="reference|boolean" />//Segment改变时是否使用颜色渐变效果
    </declare-styleable>

</resources>

布局文件创建SegmentControlView

<cn.carbs.android.segmentcontrolview.library.SegmentControlView
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_gravity="center_horizontal"
        android:paddingLeft="10dp"
        android:paddingRight="10dp"
        app:scv_FrameCornerRadius="6dp"
        app:scv_FrameWidth="1dp"
        app:scv_Gradient="true"
        app:scv_SegmentPaddingVertical="5dp"
        app:scv_TextArray="@array/segment_control_arrays_0"/>

使用方法

dependencies 
    compile 'cn.carbs.android:SegmentControlView:1.0.0'
    segmentcontrolview.setOnSegmentChangedListener(new SegmentControlView.OnSegmentChangedListener() 
        @Override
        public void onSegmentChanged(int newSelectedIndex) 
            if(viewpager != null)
                //change the second argument to true if you want the gradient effect when viewpager is changing
                viewpager.setCurrentItem(newSelectedIndex, false);//viewpager changing without animation
            
        
    );
    //set viewpager to change segment according to the state of viewpager
    segmentcontrolview.setViewPager(viewpager);
    //set the selected index of segments initiatively
    segmentcontrolview.setSelectedIndex();
    //set gradient effect if you want
    segmentcontrolview.setGradient(true);

项目地址:

https://github.com/Carbs0126/AndroidSegmentControlView

Git:

git clone https://github.com/Carbs0126/AndroidSegmentControlView.git

源码如下

package cn.carbs.android.segmentcontrolview.library;

import android.content.Context;
import android.content.res.TypedArray;
import android.graphics.Canvas;
import android.graphics.Paint;
import android.graphics.Path;
import android.graphics.Rect;
import android.graphics.RectF;
import android.support.v4.view.ViewPager;
import android.text.TextUtils;
import android.util.AttributeSet;
import android.view.MotionEvent;
import android.view.View;

import java.lang.reflect.Field;

/**
 * an SegmentControlView inspired by the UISegmentControl on IOS platform.
 * this view has many interesting such as :
 *  1. set gradient effect when segment is changing by ViewPager if needed
 *  2. set the corners' radius
 *  3. set colors of texts and background
 *  4. set titles in xml resource file
 *  5. has pressed effect when finger touches this view, you can set the dark coefficient   
 * 
 * Author   Carbs.Wang 
 * Email    yeah0126#yeah.net
 */
public class SegmentControlView extends View 

    /**
     * onSegmentChanged function will be triggered if segment changed
     */
    public interface OnSegmentChangedListener
        void onSegmentChanged(int newSelectedIndex);
    

    private static final float TOUCHED_BACKGROUND_DARK_COEFFICIENT = 0.95F;

    private static final int COLOR_PRIMARY_NORMAL = 0XFFFFFFFF;
    private static final int COLOR_PRIMARY_SELECTED = 0XFF2CA99F;

    private static final int DEFAULT_COLOR_BACKGROUND_SELECTED = COLOR_PRIMARY_SELECTED;
    private static final int DEFAULT_COLOR_BACKGROUND_NORMAL = COLOR_PRIMARY_NORMAL;
    private static final int DEFAULT_COLOR_TEXT_SELECTED = COLOR_PRIMARY_NORMAL;
    private static final int DEFAULT_COLOR_TEXT_NORMAL = COLOR_PRIMARY_SELECTED;
    private static final int DEFAULT_COLOR_FRAME = COLOR_PRIMARY_SELECTED;
    private static final int DEFAULT_TEXT_SIZE_SP = 16;
    private static final int DEFAULT_FRAME_WIDTH_PX = 2;
    private static final int DEFAULT_FRAME_CORNER_RADIUS_PX = 0;
    private static final int DEFAULT_SELECTED_INDEX = 0;
    private static final int DEFAULT_SEGMENT_PADDING_HORIZONTAL = 16;
    private static final int DEFAULT_SEGMENT_PADDING_VERTICAL = 12;
    private static final boolean DEFAULT_IS_GRADIENT = false;

    private String[] mTexts = null;

    private int mColorBackgroundSelected = DEFAULT_COLOR_BACKGROUND_SELECTED;
    private int mColorBackgroundNormal = DEFAULT_COLOR_BACKGROUND_NORMAL;
    private int mColorTextSelected = DEFAULT_COLOR_TEXT_SELECTED;
    private int mColorTextNormal = DEFAULT_COLOR_TEXT_NORMAL;
    private int mColorFrame = DEFAULT_COLOR_FRAME;
    private int mFrameWidth = DEFAULT_FRAME_WIDTH_PX;
    private int mFrameCornerRadius = DEFAULT_FRAME_CORNER_RADIUS_PX;

    private int mTextSize = 0;
    private int mSelectedIndex = DEFAULT_SELECTED_INDEX;

    //used in wrap_content mode
    private int mSegmentPaddingHorizontal = DEFAULT_SEGMENT_PADDING_HORIZONTAL;
    private int mSegmentPaddingVertical = DEFAULT_SEGMENT_PADDING_VERTICAL;

    private boolean mIsGradient = DEFAULT_IS_GRADIENT;
    private OnSegmentChangedListener mOnSegmentChangedListener;

    private float unitWidth = 0;
    private Paint paintText;        //painter of the text 
    private Paint paintBackground;  //painter of the background
    private Paint paintFrame;       //painter of the frame
    private RectF rectF;
    private RectF rectFArc;
    private Path pathFrame;

    private float textCenterYOffset;

    private int preTouchedIndex = -1;
    private int curTouchedIndex = -1;

    private ViewPager viewPager;

    public SegmentControlView(Context context) 
        super(context);
        init();
    
    public SegmentControlView(Context context, AttributeSet attrs) 
        super(context, attrs);
        initAttr(context, attrs);
        init();
    
    public SegmentControlView(Context context, AttributeSet attrs, int defStyleAttr) 
        super(context, attrs, defStyleAttr);
        initAttr(context, attrs);
        init();
    

    private void initAttr(Context context, AttributeSet attrs) 
        if (attrs == null) 
            return;
        

        TypedArray a = context.obtainStyledAttributes(attrs, R.styleable.SegmentControlView);

        int n = a.getIndexCount();
        for (int i = 0; i < n; i++) 
            int attr = a.getIndex(i);
            if(attr == R.styleable.SegmentControlView_scv_BackgroundSelectedColor)
                mColorBackgroundSelected = a.getColor(attr, DEFAULT_COLOR_BACKGROUND_SELECTED);
            else if(attr == R.styleable.SegmentControlView_scv_BackgroundNormalColor)
                mColorBackgroundNormal = a.getColor(attr, DEFAULT_COLOR_BACKGROUND_NORMAL);
            else if(attr == R.styleable.SegmentControlView_scv_TextSelectedColor)
                mColorTextSelected = a.getColor(attr, DEFAULT_COLOR_TEXT_SELECTED);
            else if(attr == R.styleable.SegmentControlView_scv_TextNormalColor)
                mColorTextNormal = a.getColor(attr, DEFAULT_COLOR_TEXT_NORMAL);
            else if(attr == R.styleable.SegmentControlView_scv_FrameColor)
                mColorFrame = a.getColor(attr, DEFAULT_COLOR_FRAME);
            else if(attr == R.styleable.SegmentControlView_scv_TextSize)
                mTextSize = a.getDimensionPixelSize(attr, sp2px(getContext(), DEFAULT_TEXT_SIZE_SP));
            else if(attr == R.styleable.SegmentControlView_scv_TextArray)
                mTexts = convertCharSequenceToString(a.getTextArray(attr));
            else if(attr == R.styleable.SegmentControlView_scv_FrameWidth)
                mFrameWidth = a.getDimensionPixelSize(attr, DEFAULT_FRAME_WIDTH_PX);
            else if(attr == R.styleable.SegmentControlView_scv_FrameCornerRadius)
                mFrameCornerRadius = a.getDimensionPixelSize(attr, DEFAULT_FRAME_CORNER_RADIUS_PX);
            else if(attr == R.styleable.SegmentControlView_scv_SelectedIndex)
                mSelectedIndex = a.getInteger(attr, DEFAULT_SELECTED_INDEX);
            else if(attr == R.styleable.SegmentControlView_scv_SegmentPaddingHorizontal)
                mSegmentPaddingHorizontal = a.getDimensionPixelSize(attr, DEFAULT_SEGMENT_PADDING_HORIZONTAL);
            else if(attr == R.styleable.SegmentControlView_scv_SegmentPaddingVertical)
                mSegmentPaddingVertical = a.getDimensionPixelSize(attr, DEFAULT_SEGMENT_PADDING_VERTICAL);
            else if(attr == R.styleable.SegmentControlView_scv_Gradient)
                mIsGradient = a.getBoolean(attr, DEFAULT_IS_GRADIENT);
            
        
        a.recycle();
    

    private void init()
        rectF = new RectF();
        rectFArc = new RectF();
        pathFrame = new Path();

        if(mTextSize == 0)
            mTextSize = sp2px(getContext(), DEFAULT_TEXT_SIZE_SP);

        paintText = new Paint();
        paintText.setAntiAlias(true);
        paintText.setTextAlign(Paint.Align.CENTER);
        paintText.setTextSize(mTextSize);

        paintBackground = new Paint();
        paintBackground.setAntiAlias(true);
        paintBackground.setStyle(Paint.Style.FILL);

        paintFrame = new Paint();
        paintFrame.setAntiAlias(true);
        paintFrame.setStyle(Paint.Style.STROKE);
        paintFrame.setStrokeWidth(mFrameWidth);
        paintFrame.setColor(mColorFrame);

        textCenterYOffset = getTextCenterYOffset(paintText.getFontMetrics());
        this.setClickable(true);
    

    @Override
    protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) 
        super.onMeasure(widthMeasureSpec, heightMeasureSpec);
        setMeasuredDimension(measureWidth(widthMeasureSpec, paintText), 
                             measureHeight(heightMeasureSpec, paintText));  
    

    @Override
    protected void onSizeChanged(int w, int h, int oldw, int oldh) 
        super.onSizeChanged(w, h, oldw, oldh);

        rectF.left = getPaddingLeft();
        rectF.top = getPaddingTop();
        rectF.right = w - getPaddingRight();
        rectF.bottom = h - getPaddingBottom();
        float inset = (float)Math.ceil(mFrameWidth / 2);
        rectF.inset(inset, inset);

        if(mTexts!= null && mTexts.length > 0)
            unitWidth = rectF.width() / mTexts.length;
        

        rectFArc.left = 0;
        rectFArc.top = 0;
        rectFArc.right = 2 * mFrameCornerRadius;
        rectFArc.bottom = 2 * mFrameCornerRadius;
    

    @Override
    protected void onDraw(Canvas canvas) 
        super.onDraw(canvas);
        if(!isStringArrayEmpty(mTexts))
            drawBackgroundAndFrameAndText(canvas);
        
    

    @Override
    public boolean onTouchEvent(MotionEvent event) 
        preTouchedIndex = curTouchedIndex;
        switch(event.getAction())
        case MotionEvent.ACTION_DOWN:
            curTouchedIndex = getTouchedIndex(event.getX(), event.getY());
            if(preTouchedIndex != curTouchedIndex)
                invalidate();
            
            break;
        case MotionEvent.ACTION_MOVE:
            curTouchedIndex = getTouchedIndex(event.getX(), event.getY());
            if(preTouchedIndex != curTouchedIndex)
                invalidate();
            
            break;
        case MotionEvent.ACTION_UP:
            curTouchedIndex = getTouchedIndex(event.getX(), event.getY());
            if(curTouchedIndex != -1)
                if(mOnSegmentChangedListener != null && mSelectedIndex != curTouchedIndex)
                    mOnSegmentChangedListener.onSegmentChanged(curTouchedIndex);
                
                mSelectedIndex = curTouchedIndex;
            
            curTouchedIndex = -1;
            if(mIsGradient && checkViewPagerOnPageChangeListener(this.viewPager))

            else
                invalidate();
            
            break;
        case MotionEvent.ACTION_CANCEL:
            curTouchedIndex = -1;
            invalidate();
            break;
        
        return super.onTouchEvent(event);
    

    public void setTextSize(int textSize)
        if(this.mTextSize != textSize)
            this.mTextSize = textSize;
            paintText.setTextSize(textSize);
            textCenterYOffset = getTextCenterYOffset(paintText.getFontMetrics());
            requestLayout();
            invalidate();
        
    

    public int getSelectedIndex()
        return mSelectedIndex;
    

    public void setSelectedIndex(int selectedIndex)
        if(mSelectedIndex != selectedIndex)
            mSelectedIndex = selectedIndex;
            if(mOnSegmentChangedListener != null)
                mOnSegmentChangedListener.onSegmentChanged(mSelectedIndex);
            
//          invalidate();
            if(mIsGradient && checkViewPagerOnPageChangeListener(this.viewPager))
            else
                invalidate();
            
        
    

    public void setTextColor(int textColorNormal, int textColorSelected)
        this.mColorTextNormal = textColorNormal;
        this.mColorTextSelected = textColorSelected;
        invalidate();
    

    public void setBackgroundColor(int backgroundColorNormal, int backgroundColorSelected)
        this.mColorBackgroundNormal = backgroundColorNormal;
        this.mColorBackgroundSelected = backgroundColorSelected;
        invalidate();
    

    public void setFrameColor(int frameColor)
        this.mColorFrame = frameColor;
        invalidate();
    

    public void setFrameWidth(int frameWidth)
        this.mFrameWidth = frameWidth;
        requestLayout();
        invalidate();
    

    public void setTexts(String[] texts)
        assertTextsValid(texts);
        if(texts == null || texts.length < 2)
            throw new IllegalArgumentException("SegmentControlView's content text array'length should larger than 1");
        
        if(checkIfEqual(this.mTexts, texts))
            return;
        
        this.mTexts = texts;
        unitWidth = rectF.width() / texts.length;
        requestLayout();
        invalidate();
    

    public int getCount()
        if(mTexts == null) return 0;
        return mTexts.length;
    

    /**
     * setViewPager(viewpager) to response to the change of ViewPager
     * @param viewPager the viewPager you want segmentcontrolview to respond with
     */
    public void setViewPager(ViewPager viewPager) 
        this.viewPager = viewPager;
        if (viewPager != null) 
            viewPager.setOnPageChangeListener(new InternalViewPagerListener());
        
    

    /**
     * set if this view has the Gradient effect when segment changed
     * @param gradient set if you want gradient effect
     */
    public void setGradient(boolean gradient)
        if(mIsGradient != gradient)
            mIsGradient = gradient;
        
    

    public boolean getGradient()
        return mIsGradient;
    

    /**
     * when segment changed, 
     * mOnSegmentChangedListener.onSegmentChanged(newSelectedIndex) will be triggered
     * @param listener OnSegmentChangedListener
     */
    public void setOnSegmentChangedListener(OnSegmentChangedListener listener)
        mOnSegmentChangedListener = listener;
    

    public void update()
        invalidate();
    

    private float getTextCenterYOffset(Paint.FontMetrics fontMetrics)
        if(fontMetrics == null) return 0;
        return Math.abs(fontMetrics.top + fontMetrics.bottom)/2;
    

    private String[] convertCharSequenceToString(CharSequence[] csArray)
        if(csArray == null) return null;
        String[] sArray = new String[csArray.length];
        for(int i = 0; i < csArray.length; i++)
            sArray[i] = csArray[i].toString();
        
        return sArray;
    

    private void assertTextsValid(String[] texts)
        if(texts == null || texts.length < 2)
            throw new IllegalArgumentException("SegmentControlView's content text array'length should larger than 1");
        
    

    private boolean checkViewPagerOnPageChangeListener(ViewPager viewPager)
        if(viewPager == null) return false;
        Field field = null;
        try 
            field = ViewPager.class.getDeclaredField("mOnPageChangeListener");
            if(field == null) return false;
            field.setAccessible(true);
            Object o = field.get(viewPager);
            if(o != null && o instanceof InternalViewPagerListener)
                return true;
            
         catch (Exception e) 
            return false;
        
        return false;
    

    private int getTouchedIndex(float x, float y)

        if(!rectF.contains(x, y))
            return -1;
        
        for(int i = 0; i < mTexts.length; i++)
            if(rectF.left + i * unitWidth <= x && x < rectF.left + (i + 1) * unitWidth)
                return i;
            
        
        return -1;
    

    private boolean checkIfEqual(String[] a, String[] b)
        if(a == null && b == null)
            return true;
        
        if(a != null)
            if(b == null)
                return false;
            
            if(a.length != b.length)
                return false;
            
            for(int i = 0; i < a.length; i++)
                if(a[i] == null && b[i] == null)
                    continue;
                
                if(a[i] != null && a[i].equals(b[i]))
                    continue;
                else
                    return false;
                
            
            return true;
        
        return false;
    

    private int measureWidth(int measureSpec, Paint paint)   
        int result = 0;  
        int specMode = MeasureSpec.getMode(measureSpec);  
        int specSize = MeasureSpec.getSize(measureSpec);  

        if (specMode == MeasureSpec.EXACTLY)   
            result = specSize;
         else   
            int maxWidth = 0;
            int maxWidthItem = getMaxWidthOfTextArray(mTexts, paint);
            maxWidth = (maxWidthItem + 2 * mSegmentPaddingHorizontal + 2 * mFrameWidth) * mTexts.length;

            if(maxWidth < 2 * mFrameCornerRadius)
                maxWidth = 2 * mFrameCornerRadius;
            

            result = this.getPaddingLeft() + this.getPaddingRight() + maxWidth;//MeasureSpec.UNSPECIFIED
            if (specMode == MeasureSpec.AT_MOST) 
                result = Math.min(result, specSize);  
            
        
        return result;  
      

    private int measureHeight(int measureSpec, Paint paint)   
        int result = 0;  
        int specMode = MeasureSpec.getMode(measureSpec);  
        int specSize = MeasureSpec.getSize(measureSpec);  

        if (specMode == MeasureSpec.EXACTLY)   
            result = specSize;  
         else   
            int maxHeight = 0;
            int maxHeightItem = getMaxHeightOfTextArray(mTexts, paint);

            maxHeight = maxHeightItem + 2 * mSegmentPaddingVertical + 2 * mFrameWidth;

            if(maxHeight < 2 * mFrameCornerRadius)
                maxHeight = 2 * mFrameCornerRadius;
            

            result = this.getPaddingTop() + this.getPaddingBottom() + maxHeight;//MeasureSpec.UNSPECIFIED
            if (specMode == MeasureSpec.AT_MOST)   
                result = Math.min(result, specSize);  
              
          
        return result;
    

    private int getMaxWidthOfTextArray(String[] array, Paint paint)
        if(array == null)
            return 0;
        
        int maxWidth = 0;
        for(String item : array)
            if(item != null)
                int itemWidth = getTextWidth(item, paint);
                maxWidth = Math.max(itemWidth, maxWidth);
            
        
        return maxWidth;
    

    private int getMaxHeightOfTextArray(String[] array, Paint paint)
        if(array == null)
            return 0;
        
        int maxHeight = 0;
        for(String item : array)
            if(item != null)
                int itemHeight = getTextHeight(item, paint);
                maxHeight = Math.max(itemHeight, maxHeight);
            
        
        return maxHeight;
    

    private void drawBackgroundAndFrameAndText(Canvas canvas)
        int curBackgroundColor = 0;
        int curTextColor = 0;
        for(int i = 0; i < mTexts.length; i++)
            float left = rectF.left + unitWidth * i;
            pathFrame.reset();
            if(i == 0)
                pathFrame.moveTo(rectF.left, rectF.top + mFrameCornerRadius);
                rectFArc.offsetTo(rectF.left, rectF.top);
                pathFrame.arcTo(rectFArc, 180, 90);
                pathFrame.lineTo(rectF.left + unitWidth, rectF.top);
                pathFrame.lineTo(rectF.left + unitWidth, rectF.bottom);
                pathFrame.lineTo(rectF.left + mFrameCornerRadius, rectF.bottom);
                rectFArc.offsetTo(rectF.left, rectF.bottom - 2 * mFrameCornerRadius);
                pathFrame.arcTo(rectFArc, 90, 90);
            else if(i == (mTexts.length - 1))
                pathFrame.moveTo(rectF.left + i * unitWidth, rectF.top);
                pathFrame.lineTo(rectF.right - mFrameCornerRadius, rectF.top);
                rectFArc.offsetTo(rectF.right - 2 * mFrameCornerRadius, rectF.top);
                pathFrame.arcTo(rectFArc, 270, 90);
                pathFrame.lineTo(rectF.right, rectF.bottom - mFrameCornerRadius);
                rectFArc.offsetTo(rectF.right - 2 * mFrameCornerRadius, rectF.bottom - 2 * mFrameCornerRadius);
                pathFrame.arcTo(rectFArc, 0, 90);
                pathFrame.lineTo(rectF.left + i * unitWidth, rectF.bottom);
            else
                pathFrame.moveTo(left, rectF.top);
                pathFrame.lineTo(left + unitWidth, rectF.top);
                pathFrame.lineTo(left + unitWidth, rectF.bottom);
                pathFrame.lineTo(left, rectF.bottom);
            
            pathFrame.close();

            if(!mIsGradient)
                if(i == mSelectedIndex)
                    curBackgroundColor = mColorBackgroundSelected;
                    curTextColor = mColorTextSelected;
                else
                    curBackgroundColor = mColorBackgroundNormal;
                    curTextColor = mColorTextNormal;
                
            
            if(mIsGradient)
                if(viewPagerPositionOffset != 0f)
                    if(i == viewPagerPosition)
                        curBackgroundColor = getEvaluateColor(viewPagerPositionOffset, mColorBackgroundSelected, mColorBackgroundNormal);
                        curTextColor = getEvaluateColor(viewPagerPositionOffset, mColorTextSelected, mColorTextNormal);
                    else if(i == viewPagerPosition + 1)
                        curBackgroundColor = getEvaluateColor(viewPagerPositionOffset, mColorBackgroundNormal, mColorBackgroundSelected);
                        curTextColor = getEvaluateColor(viewPagerPositionOffset, mColorTextNormal, mColorTextSelected);
                    else
                        curBackgroundColor = mColorBackgroundNormal;
                        curTextColor = mColorTextNormal;
                    
                else
                    if(i == mSelectedIndex)
                        curBackgroundColor = mColorBackgroundSelected;
                        curTextColor = mColorTextSelected;
                    else
                        curBackgroundColor = mColorBackgroundNormal;
                        curTextColor = mColorTextNormal;
                    
                
            
            paintBackground.setColor(curBackgroundColor);

            if(curTouchedIndex == i)
                paintBackground.setColor(getDarkColor(curBackgroundColor, TOUCHED_BACKGROUND_DARK_COEFFICIENT));
            
            canvas.drawPath(pathFrame, paintBackground);
            canvas.drawPath(pathFrame, paintFrame);

            paintText.setColor(curTextColor);
            canvas.drawText(mTexts[i], left + unitWidth / 2,rectF.centerY() + textCenterYOffset, paintText);
        
    

    private int viewPagerPosition = -1;
    private float viewPagerPositionOffset = 0f;
    private class InternalViewPagerListener implements ViewPager.OnPageChangeListener 

        @Override
        public void onPageScrolled(int position, float positionOffset, int positionOffsetPixels) 
            if(mIsGradient)
                mSelectedIndex = position;
                viewPagerPosition = position;
                viewPagerPositionOffset = positionOffset;
                invalidate();
            
        

        @Override
        public void onPageScrollStateChanged(int state) 
        

        @Override
        public void onPageSelected(int position) 
            if(mIsGradient)
            else
                SegmentControlView.this.setSelectedIndex(position);
            
        
    

    private int getDarkColor(int color, float darkCoefficient)

        int a = (color & 0xff000000) >>> 24;
        int r = (color & 0x00ff0000) >>> 16;
        int g = (color & 0x0000ff00) >>> 8;
        int b = (color & 0x000000ff) >>> 0;

        r = (int)(r * darkCoefficient);
        g = (int)(g * darkCoefficient);
        b = (int)(b * darkCoefficient);

        return a << 24 | r << 16 | g << 8 | b;
    

    private int getEvaluateColor(float fraction, int startColor, int endColor)

        int a, r, g, b;

        int sA = (startColor & 0xff000000) >>> 24;
        int sR = (startColor & 0x00ff0000) >>> 16;
        int sG = (startColor & 0x0000ff00) >>> 8;
        int sB = (startColor & 0x000000ff) >>> 0;

        int eA = (endColor & 0xff000000) >>> 24;
        int eR = (endColor & 0x00ff0000) >>> 16;
        int eG = (endColor & 0x0000ff00) >>> 8;
        int eB = (endColor & 0x000000ff) >>> 0;

        a = (int)(sA + (eA - sA) * fraction);
        r = (int)(sR + (eR - sR) * fraction);
        g = (int)(sG + (eG - sG) * fraction);
        b = (int)(sB + (eB - sB) * fraction);

        return a << 24 | r << 16 | g << 8 | b;
    

    private boolean isStringArrayEmpty(String[] array)
        return (array == null || array.length == 0);
    

    private static int sp2px(Context context, float spValue)   
        final float fontScale = context.getResources().getDisplayMetrics().scaledDensity;  
        return (int) (spValue * fontScale + 0.5f);  
     

    private int getTextWidth(String text, Paint paint)
        if(!TextUtils.isEmpty(text))
            return (int)(paint.measureText(text) + 0.5f);
        
        return -1;
    

    private int getTextHeight(String text, Paint paint)
        if(!TextUtils.isEmpty(text))
            Rect textBounds = new Rect();
            paint.getTextBounds(text, 0, text.length(), textBounds);
            return textBounds.height();
        
        return -1;
    

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