Android开发:史上最简单方便的viewpager加indicator的方法
来源:互联网 发布:分班软件fenban 编辑:程序博客网 时间:2024/04/30 10:59
开发Android应用的时候,每次给viewpager加indicator的时候,是不是感觉到很无力呢,看看JakeWharton大神的github,要么要应用library,要么把code加到自己的项目中,还要加attrs,加各种value,比如colors,strings,其实超过90%以上的时候,我们的需要其实很简单,只是在底部的中间加上指示圆点,而且JakeWharton大神的默认的是空心圆圈,还要在onDraw中改成实心的圆形,是不是厌烦啦,每次都要这么麻烦,好了,终极简单的解决方法出来了,想看效果:
当然,这个效果照搬别人的图,不过实现这个效果,我用了超级简单的方法,一劳永逸:
只要三个步骤,复制粘贴,再复制粘贴,然后在activity中写几行代码即可。
- 第一步,复制,粘贴
新建一个类,叫做CircleIndicatorHelper,然后复制如下的代码进去:
public class CircleIndicatorHelper {private CirclePageIndicator mCircleIndicator;private Context mContext;public CircleIndicatorHelper(Context context) {mCircleIndicator = new CirclePageIndicator(context);mContext = context;}public void setViewpager(ViewPager viewPager) {ViewGroup parentView = (ViewGroup) viewPager.getParent();LayoutParams lp = new LayoutParams(LayoutParams.MATCH_PARENT, LayoutParams.WRAP_CONTENT, Gravity.BOTTOM);lp.setMargins(0, 0, 0, dpToPx(8));mCircleIndicator.setLayoutParams(lp);parentView.addView(mCircleIndicator);mCircleIndicator.setViewPager(viewPager);}public void setFillColor(String colorString) {int color = Color.parseColor(colorString);mCircleIndicator.setFillColor(color);}public void setDefaultColor(String colorString) {int color = Color.parseColor(colorString);mCircleIndicator.setDefaultColor(color);}public void setRadius(int radius) {mCircleIndicator.setRadius(dpToPx(radius));}private int dpToPx(int dp) {DisplayMetrics resourec = mContext.getResources().getDisplayMetrics();return (int) TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_DIP, dp, resourec);}}
- 第二部,再新建一个类,名字叫复制,粘贴
public class CirclePageIndicator extends View{ private static final int INVALID_POINTER = -1; private float mRadius;// private final Paint mPaintPageFill = new Paint(ANTI_ALIAS_FLAG); private final Paint mPaintStroke = new Paint(ANTI_ALIAS_FLAG); private final Paint mPaintFill = new Paint(ANTI_ALIAS_FLAG); private ViewPager mViewPager; private ViewPager.OnPageChangeListener mListener; private int mCurrentPage; private int mSnapPage; private float mPageOffset; private int mScrollState; private int mOrientation; private boolean mCentered; private boolean mSnap; private float cicleSpace; public CirclePageIndicator(Context context) { this(context, null); } public CirclePageIndicator(Context context, AttributeSet attrs) { this(context, attrs, 0); } public CirclePageIndicator(Context context, AttributeSet attrs, int defStyle) { super(context, attrs, defStyle); if (isInEditMode()) return; final Resources res = getResources(); final int defaultFillColor = Color.parseColor("#7F7F7F"); final int defaultStrokeColor = Color.parseColor("#D0D0D0"); final float defaultRadius = TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_DIP, 3, res.getDisplayMetrics()); mCentered = true; mPaintStroke.setStyle(Style.FILL); mPaintStroke.setColor(defaultStrokeColor); mPaintFill.setStyle(Style.FILL); mPaintFill.setColor(defaultFillColor); mRadius = defaultRadius; cicleSpace = mRadius*3; } public void setCentered(boolean centered) { mCentered = centered; invalidate(); } public boolean isCentered() { return mCentered; } public void setDefaultColor(int strokeColor) { mPaintStroke.setColor(strokeColor); invalidate(); } public void setFillColor(int fillColor) { mPaintFill.setColor(fillColor); invalidate(); } public void setRadius(float radius) { mRadius = radius; cicleSpace = radius*3; invalidate(); } @Override protected void onDraw(Canvas canvas) { super.onDraw(canvas); if (mViewPager == null) { return; } final int count = mViewPager.getAdapter().getCount(); if (count == 0) { return; } if (mCurrentPage >= count) { setCurrentItem(count - 1); return; } int longSize; int longPaddingBefore; int longPaddingAfter; int shortPaddingBefore; if (mOrientation == HORIZONTAL) { longSize = getWidth(); longPaddingBefore = getPaddingLeft(); longPaddingAfter = getPaddingRight(); shortPaddingBefore = getPaddingTop(); } else { longSize = getHeight(); longPaddingBefore = getPaddingTop(); longPaddingAfter = getPaddingBottom(); shortPaddingBefore = getPaddingLeft(); } final float shortOffset = shortPaddingBefore + mRadius; float longOffset = longPaddingBefore + mRadius; if (mCentered) { longOffset += ((longSize - longPaddingBefore - longPaddingAfter) / 2.0f) - ((count * cicleSpace) / 2.0f); } float dX; float dY; float pageFillRadius = mRadius; //Draw stroked circles for (int iLoop = 0; iLoop < count; iLoop++) { float drawLong = longOffset + (iLoop * cicleSpace); if (mOrientation == HORIZONTAL) { dX = drawLong; dY = shortOffset; } else { dX = shortOffset; dY = drawLong; } // Only paint fill if not completely transparent canvas.drawCircle(dX, dY, mRadius, mPaintStroke); } //Draw the filled circle according to the current scroll float cx = (mSnap ? mSnapPage : mCurrentPage) * cicleSpace; if (!mSnap) { cx += mPageOffset * cicleSpace; } if (mOrientation == HORIZONTAL) { dX = longOffset + cx; dY = shortOffset; } else { dX = shortOffset; dY = longOffset + cx; } canvas.drawCircle(dX, dY, mRadius, mPaintFill); } public void setViewPager(ViewPager view) { if (mViewPager == view) { return; } if (mViewPager != null) { mViewPager.setOnPageChangeListener(null); } if (view.getAdapter() == null) { throw new IllegalStateException("ViewPager does not have adapter instance."); } mViewPager = view; mViewPager.setOnPageChangeListener(new OnPageChangeListener() {@Overridepublic void onPageSelected(int position) { if (mSnap || mScrollState == ViewPager.SCROLL_STATE_IDLE) { mCurrentPage = position; mSnapPage = position; invalidate(); } if (mListener != null) { mListener.onPageSelected(position); } }@Overridepublic void onPageScrolled(int position, float positionOffset, int positionOffsetPixels) {mCurrentPage = position; mPageOffset = positionOffset; invalidate(); if (mListener != null) { mListener.onPageScrolled(position, positionOffset, positionOffsetPixels); }}@Overridepublic void onPageScrollStateChanged(int state) { mScrollState = state; if (mListener != null) { mListener.onPageScrollStateChanged(state); }}}); invalidate(); } public void setViewPager(ViewPager view, int initialPosition) { setViewPager(view); setCurrentItem(initialPosition); } public void setCurrentItem(int item) { if (mViewPager == null) { throw new IllegalStateException("ViewPager has not been bound."); } mViewPager.setCurrentItem(item); mCurrentPage = item; invalidate(); } @Override protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) { if (mOrientation == HORIZONTAL) { setMeasuredDimension(measureLong(widthMeasureSpec), measureShort(heightMeasureSpec)); } else { setMeasuredDimension(measureShort(widthMeasureSpec), measureLong(heightMeasureSpec)); } } /** * Determines the width of this view * * @param measureSpec * A measureSpec packed into an int * @return The width of the view, honoring constraints from measureSpec */ private int measureLong(int measureSpec) { int result; int specMode = MeasureSpec.getMode(measureSpec); int specSize = MeasureSpec.getSize(measureSpec); if ((specMode == MeasureSpec.EXACTLY) || (mViewPager == null)) { //We were told how big to be result = specSize; } else { //Calculate the width according the views count final int count = mViewPager.getAdapter().getCount(); result = (int)(getPaddingLeft() + getPaddingRight() + (count * 2 * mRadius) + (count - 1) * mRadius + 1); //Respect AT_MOST value if that was what is called for by measureSpec if (specMode == MeasureSpec.AT_MOST) { result = Math.min(result, specSize); } } return result; } /** * Determines the height of this view * * @param measureSpec * A measureSpec packed into an int * @return The height of the view, honoring constraints from measureSpec */ private int measureShort(int measureSpec) { int result; int specMode = MeasureSpec.getMode(measureSpec); int specSize = MeasureSpec.getSize(measureSpec); if (specMode == MeasureSpec.EXACTLY) { //We were told how big to be result = specSize; } else { //Measure the height result = (int)(2 * mRadius + getPaddingTop() + getPaddingBottom() + 1); //Respect AT_MOST value if that was what is called for by measureSpec if (specMode == MeasureSpec.AT_MOST) { result = Math.min(result, specSize); } } return result; } @Override public void onRestoreInstanceState(Parcelable state) { SavedState savedState = (SavedState)state; super.onRestoreInstanceState(savedState.getSuperState()); mCurrentPage = savedState.currentPage; mSnapPage = savedState.currentPage; requestLayout(); } @Override public Parcelable onSaveInstanceState() { Parcelable superState = super.onSaveInstanceState(); SavedState savedState = new SavedState(superState); savedState.currentPage = mCurrentPage; return savedState; } static class SavedState extends BaseSavedState { int currentPage; public SavedState(Parcelable superState) { super(superState); } private SavedState(Parcel in) { super(in); currentPage = in.readInt(); } @Override public void writeToParcel(Parcel dest, int flags) { super.writeToParcel(dest, flags); dest.writeInt(currentPage); } @SuppressWarnings("UnusedDeclaration") 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]; } }; } }
代码有点长啊,不过只是复制粘贴,应该没什么问题吧
- 第三部,在含有viewpager的activity,引用如下几句代码,即可加上viewpagerindicator了
private CircleIndicatorHelper mIndicatorHelper = new CircleIndicatorHelper(this);mIndicatorHelper.setViewpager(mViewPager);
好了,就是这么的简单,这么的任性,从此再也不用担心加小圆圈了,不过问题来了,怎么自定义呢,我要的圆圈的颜色,大小,间距,OK,这些都是一句代码搞定;
mIndicatorHelper.setFillColor("#651717");mIndicatorHelper.setDefaultColor("#00A2E8");mIndicatorHelper.setRadius(8);
设置填充颜色,设置默认颜色,设置大小,简单便捷
好了,最后,别忘了,把viewpager的parent View设置成FrameLayout噢
0 0
- Android开发:史上最简单方便的viewpager加indicator的方法
- android viewpager tab indicator炫酷的Tab动画效果
- Android 使用ViewPager Indicator时,标题显示不全的问题
- Android开源控件ViewPager Indicator的使用方法
- Android中级:轮播图(二):ViewPager实现indicator的滚动
- android学习记录6:实现ViewPager的Indicator
- Android开源控件ViewPager Indicator的使用方法
- android-viewpager-indicator
- ViewPager和Indicator使用时的美化
- android开发--ViewPager的简单应用
- TabLayout加ViewPager的简单使用
- Android 简单方便的延时
- 指示器indicator的设置(方便的第三方)
- Android环境搭建的最新方法,方便、简单、极度容易。
- android 超级简单方便的注解注入控件和方法
- android仿微信viewpager indicator+frament
- Android ViewPager内容部分随手势上下滑动隐藏与显示Indicator效果的实现
- Android ViewPager内容部分随手势上下滑动隐藏与显示Indicator效果的实现
- 给新建的Cocos2d-x 3.x 的Win32工程添加CocoStudio库
- 在Maven中新增自定的jar包
- JQuery滚动图片
- 程序员的八种级别,你在哪一级?
- Python 实现简单的自定义异常类型
- Android开发:史上最简单方便的viewpager加indicator的方法
- Maven的使用
- android开发,修改默认界面的背景色
- TCP/IP协议中的三个参数的理解
- java动态代理(JDK和cglib)
- StringTokenizer使用
- Java中String类的方法及说明
- Linux内核信号处理机制介绍
- 年轻程序员最需要学什么?自律!