模仿小米安全中心检测效果
废话少说，咱们先上效果图：
github地址： https://github.com/niniloveyou/GradeProgressView
这个效果的使用场景并不多，主要是各种检测的时候，比如垃圾清理，手机安全检测， 当然如果你不嫌弃这个效果丑， 也可以用作进度条。哈哈。
下面说点干货分析下这个效果怎么实现：
拿到这个效果首先想想主要有哪些技术难点：
1.进度条
2.中间的指针怎么弄
1.进度条
有人说进度条还不容易吗？ 就这样写：
mPaint.setPathEffect(new DashPathEffect(new float[]{dashWith, dashSpace}, 。。。)); canvas.drawArc(mRectF, 135, 270, false, mPaint); mPaint.setColor(Color.WHITE); canvas.drawArc(mRectF, 135, degree, false, mPaint);
设置个PathEffect
然后画个圆弧，给画笔设置颜色然后根据进度，算出角度， 然后再画出一个圆弧，覆盖第一个圆弧的部分不就行了。废话这么多。
不过我想说的too young too simple. 当时我也是这样想的，于是就实现吧！ 做好了先画个50% （也就是第二个圆弧覆盖第一个圆弧的一半）试试，不错啊perfect看来是这样的， 再来个30%试试尼玛不对啊， 怎么小格子没有重合，有点错位啊。MDZZ
后来想了一个简单点的办法，不覆盖，画两个圆弧， 但是这两个圆弧是对接起来的。 比如第一个圆弧，画一半，第二个画一半。
//draw background arc canvas.drawArc(mRectF, 135 + degree, 270 - degree, false, mPaint); //draw progress arc canvas.drawArc(mRectF, 135, degree, false, mProgressPaint);
2.中间的指针怎么弄
先画出指针的路径
mPointerPath = new Path(); mPointerPath.moveTo(centerX + pointRadius, centerY - 7); mPointerPath.lineTo(centerX + pointRadius, centerY + 7); mPointerPath.lineTo(mRectF.right - pointGap - lineWidth / 2,centerY); mPointerPath.lineTo(centerX + pointRadius, centerY - 7); mPointerPath.close();
在中心draw一个小圆
然后draw指针,这样当画布旋转时指针自然也就旋转了，不懂得要去看看canvas.save(), canvas.restore()的作用
//draw pointer canvas.drawCircle(centerX, centerY, pointRadius,mInnerCirclePaint); canvas.save(); canvas.rotate(135 + degree, centerX, centerY); canvas.drawPath(mPointerPath, mPointerPaint); canvas.restore();
下面上完整代码：
package deadline.grade; import android.animation.ValueAnimator; import android.annotation.TargetApi; import android.content.Context; import android.graphics.Canvas; import android.graphics.Color; import android.graphics.DashPathEffect; import android.graphics.Paint; import android.graphics.Path; import android.graphics.RectF; import android.os.Build; import android.support.annotation.IntRange; import android.util.AttributeSet; import android.util.Log; import android.view.View; import android.view.animation.AccelerateDecelerateInterpolator; /** * @author deadline * @time 2016/9/24 */ public class GradeProgressView extends View { private static final String TAG = GradeProgressView.class.getSimpleName(); private static final int DEFAULT_PROGRESS_COLOR = Color.WHITE; private static final int DEFAULT_BACKGROUND_COLOR = 0x5AFFFFFF; private int mBackgroundColor = DEFAULT_BACKGROUND_COLOR; private int mProgressColor = DEFAULT_PROGRESS_COLOR; //进度条的每格线宽，间距，长度 private int dashWith = 4; private int dashSpace = 6; private int lineWidth = 60; //最外圈线的宽度和与进度条之间的间距 private int outLineWidth = 5; private int gapWidth = 25; //指针的线宽度， 半径， 以及指针与进度条的间距 private int pointLineWidth = 10; private int pointRadius = 25; private int pointGap = 20; private int mProgress = 0; //外线 private RectF mOuterRectF; private Paint mOuterPaint; //进度条 private RectF mRectF; private Paint mPaint; private Paint mProgressPaint; //指针 private Paint mInnerCirclePaint; private Paint mPointerPaint; private Path mPointerPath; private float centerX; private float centerY; private ValueAnimator animator; private OnProgressChangeListener mListener; public GradeProgressView(Context context) { this(context, null); } public GradeProgressView(Context context, AttributeSet attrs) { this(context, attrs, 0); } public GradeProgressView(Context context, AttributeSet attrs, int defStyleAttr) { super(context, attrs, defStyleAttr); setup(); } @TargetApi(Build.VERSION_CODES.LOLLIPOP) public GradeProgressView(Context context, AttributeSet attrs, int defStyleAttr, int defStyleRes) { super(context, attrs, defStyleAttr, defStyleRes); } private void setup() { mRectF = new RectF(); mOuterRectF = new RectF(); mOuterPaint = new Paint(Paint.ANTI_ALIAS_FLAG); mOuterPaint.setStrokeWidth(outLineWidth); mOuterPaint.setColor(mBackgroundColor); mOuterPaint.setStyle(Paint.Style.STROKE); mPaint = new Paint(Paint.ANTI_ALIAS_FLAG); mPaint.setStrokeWidth(lineWidth); mPaint.setColor(mBackgroundColor); mPaint.setStyle(Paint.Style.STROKE); mPaint.setPathEffect(new DashPathEffect(new float[]{dashWith, dashSpace}, dashSpace)); mProgressPaint = new Paint(Paint.ANTI_ALIAS_FLAG); mProgressPaint.setStrokeWidth(lineWidth); mProgressPaint.setColor(mProgressColor); mProgressPaint.setStyle(Paint.Style.STROKE); mProgressPaint.setPathEffect(new DashPathEffect(new float[]{dashWith, dashSpace}, dashSpace)); mPointerPaint = new Paint(Paint.ANTI_ALIAS_FLAG); mPointerPaint.setStrokeWidth(pointLineWidth / 2); mPointerPaint.setColor(mProgressColor); mPointerPaint.setStyle(Paint.Style.FILL_AND_STROKE); mPointerPaint.setStrokeCap(Paint.Cap.ROUND); mPointerPaint.setShadowLayer(4, 3, 0, 0x20000000); mInnerCirclePaint = new Paint(Paint.ANTI_ALIAS_FLAG); mInnerCirclePaint.setStrokeWidth(pointLineWidth); mInnerCirclePaint.setColor(mProgressColor); mInnerCirclePaint.setStyle(Paint.Style.STROKE); mInnerCirclePaint.setShadowLayer(4, 3, 0, 0x20000000); } @Override protected void onSizeChanged(int w, int h, int oldw, int oldh) { super.onSizeChanged(w, h, oldw, oldh); int value = outLineWidth / 2; mOuterRectF.set(value, value, w - value, h - value); int gap = lineWidth / 2 + outLineWidth + gapWidth; mRectF.set(mOuterRectF.left + gap, mOuterRectF.top + gap, mOuterRectF.right - gap, mOuterRectF.bottom - gap); centerX = mRectF.centerX(); centerY = mRectF.centerY(); mPointerPath = new Path(); mPointerPath.moveTo(centerX + pointRadius, centerY - 7); mPointerPath.lineTo(centerX + pointRadius, centerY + 7); mPointerPath.lineTo(mRectF.right - pointGap - lineWidth / 2, centerY); mPointerPath.lineTo(centerX + pointRadius, centerY - 7); mPointerPath.close(); } @Override protected void onDraw(Canvas canvas) { super.onDraw(canvas); float degree = 2.7f * mProgress; //draw out arc canvas.drawArc(mOuterRectF, 135, 270, false, mOuterPaint); //draw background arc canvas.drawArc(mRectF, 135 + degree, 270 - degree, false, mPaint); //draw progress arc canvas.drawArc(mRectF, 135, degree, false, mProgressPaint); //draw pointer canvas.drawCircle(centerX, centerY, pointRadius, mInnerCirclePaint); canvas.save(); canvas.rotate(135 + degree, centerX, centerY); canvas.drawPath(mPointerPath, mPointerPaint); canvas.restore(); } @Override protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) { super.onMeasure(widthMeasureSpec, heightMeasureSpec); int measureWidth = MeasureSpec.getSize(widthMeasureSpec); int measureHeight = MeasureSpec.getSize(heightMeasureSpec); setMeasuredDimension(Math.min(measureHeight, measureWidth), Math.min(measureHeight, measureWidth)); } public void setOnProgressChangeListener(OnProgressChangeListener listener){ this.mListener = listener; } public int getProgressColor() { return mProgressColor; } public void setProgressColor(int progressColor) { this.mProgressColor = progressColor; if(mProgressPaint != null){ mProgressPaint.setColor(mProgressColor); } if(mPointerPaint != null){ mPointerPaint.setColor(mProgressColor); } if(mInnerCirclePaint != null){ mInnerCirclePaint.setColor(mProgressColor); } postInvalidate(); } public int getBackgroundColor() { return mBackgroundColor; } public void setBackgroundColor(int backgroundColor) { this.mBackgroundColor = backgroundColor; if(mPaint != null){ mPaint.setColor(mBackgroundColor); } if(mOuterPaint != null){ mOuterPaint.setColor(mBackgroundColor); } postInvalidate(); } public int getLineWidth() { return lineWidth; } public void setLineWidth(int lineWidth) { this.lineWidth = lineWidth; if(mPaint != null){ mPaint.setStrokeWidth(lineWidth); } if(mProgressPaint != null){ mProgressPaint.setStrokeWidth(lineWidth); } postInvalidate(); } public int getOutLineWidth() { return outLineWidth; } public void setOutLineWidth(int outLineWidth) { this.outLineWidth = outLineWidth; if(mOuterPaint != null){ mOuterPaint.setStrokeWidth(outLineWidth); } postInvalidate(); } public int getGapWidth() { return gapWidth; } public void setGapWidth(int gapWidth) { this.gapWidth = gapWidth; } public int getProgress() { return mProgress; } public void setProgress(@IntRange(from = 0, to = 100) int progress) { if(progress > 100){ progress = 100; } if(progress < 0){ progress = 0; } this.mProgress = progress; if(mListener != null){ mListener.onProgressChanged(GradeProgressView.this, mProgress); } postInvalidate(); } public void setProgressWidthAnimation(@IntRange(from = 0, to = 100) int progress){ if(progress > 100){ progress = 100; } if(progress < 0){ progress = 0; } if(animator != null && animator.isRunning()){ animator.cancel(); animator = null; } animator = ValueAnimator.ofInt(mProgress, progress); int duration = 10 * Math.abs(progress - mProgress); animator.setDuration(duration); animator.setInterpolator(new AccelerateDecelerateInterpolator()); animator.addUpdateListener(new ValueAnimator.AnimatorUpdateListener() { @Override public void onAnimationUpdate(ValueAnimator valueAnimator) { int value = (int)valueAnimator.getAnimatedValue(); if(mProgress != value) { mProgress = value; if(mListener != null){ mListener.onProgressChanged(GradeProgressView.this, mProgress); } postInvalidate(); } } }); animator.start(); } @Override protected void onDetachedFromWindow() { super.onDetachedFromWindow(); if(animator != null){ animator.cancel(); animator = null; } } public interface OnProgressChangeListener{ void onProgressChanged(GradeProgressView gradeProgressView, int progress); } }
以上就是本文的全部内容，希望对大家的学习有所帮助，也希望大家多多支持脚本之家。