Android 自定义垂直，旋转，圆形进度提示 自定义Seekbar
SeekBar是用来调节参数值的，系统默认的一般都不太适合我们，需要我们自定义， 里面也有一个RxJava背压的具体应用 废话不多说，看图 package com.example.helang.seekbar; import android.content.Context; import android.graphics.Bitmap; import android.graphics.Canvas; import android.graphics.Color; import android.graphics.Matrix; import android.graphics.Paint; import android.graphics.RectF; import android.graphics.drawable.BitmapDrawable; import android.graphics.drawable.Drawable; import android.support.annotation.Nullable; import android.util.AttributeSet; import android.view.MotionEvent; import android.view.View; import java.util.concurrent.TimeUnit; import io.reactivex.Observable; import io.reactivex.ObservableEmitter; import io.reactivex.ObservableOnSubscribe; import io.reactivex.android.schedulers.AndroidSchedulers; import io.reactivex.functions.Consumer; /** * 自定义拖动seekBar */ public class CustomSeekBar extends View { private static final String TAG = "CustomSeekBar"; private static final int radius = 65;//中间圆形进度条的半径 private static final int thumbSize = 200; private int backgroundLineSize = 10;//背景线的宽度 private int foregroundLineSize = 18;//进度的宽度 private int lineSize;//整条背景线的长度 private float touchY; private Bitmap thumbBitmap; private Paint paint; private Paint circlePaint;//绘制进度条的paint private RectF backgroundLineRect = new RectF();//背景矩形 private RectF foregroundLineRect = new RectF();//进度矩形 private float currentDegrees = 0;//当前的进度，百分比例，不带百分号 private OnProgressListener onProgressListener; public void setOnProgressListener(OnProgressListener onProgressListener) { this.onProgressListener = onProgressListener; } public CustomSeekBar(Context context) { this(context,null); } public CustomSeekBar(Context context, @Nullable AttributeSet attrs) { this(context, attrs,0); } public CustomSeekBar(Context context, @Nullable AttributeSet attrs, int defStyleAttr) { super(context, attrs, defStyleAttr); initBitmap(); initPaint(); } /** * init bitmap */ private void initBitmap(){ thumbBitmap = drawableToBitmap(thumbSize,getResources().getDrawable(R.drawable.circle)); } /** * init paint */ private void initPaint() { paint = new Paint(); paint.setStyle(Paint.Style.FILL); paint.setTextSize(10); //初始化圆形进度条的Paint circlePaint = new Paint(); circlePaint.setAntiAlias(true); // 抗锯齿 circlePaint.setDither(true); // 防抖动 circlePaint.setStrokeWidth(10); circlePaint.setShader(null); // 清除上一次的shader circlePaint.setStyle(Paint.Style.STROKE); // 设置绘制的圆为空心 circlePaint.setShadowLayer(10, 10, 10, Color.RED); circlePaint.setColor(Color.BLUE); // 设置圆弧的颜色 circlePaint.setStrokeCap(Paint.Cap.ROUND); // 把每段圆弧改成圆角的 } @Override protected void onLayout(boolean changed, int left, int top, int right, int bottom) { super.onLayout(changed, left, top, right, bottom); } @Override protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) { super.onMeasure(widthMeasureSpec, heightMeasureSpec); } @Override protected void onDraw(Canvas canvas) { super.onDraw(canvas); drawLine(canvas); drawThumb(canvas); drawCircleProgress(canvas); } /** * draw circle * @param canvas */ private void drawCircleProgress(Canvas canvas){ RectF oval = new RectF(thumbSize/2-radius, thumbSize/2-radius, thumbSize/2+radius, thumbSize/2+radius); // 圆的外接正方形 float alphaAngle = currentDegrees * 360.0f / 100 * 1.0f; // 计算每次画圆弧时扫过的角度，这里计算要注意分母要转为float类型，否则alphaAngle永远为0 canvas.drawArc(oval, -90, alphaAngle, false, circlePaint); } /** * draw thumb * @param canvas */ private void drawThumb(Canvas canvas){ //添加旋转,Matrix是Bitmap旋转的关键，用于bitmap一些补间动画的操作 canvas.translate((getWidth()-thumbSize)/2,(100-currentDegrees)/100*lineSize); Matrix matrix = new Matrix(); matrix.setRotate(currentDegrees*10,thumbSize/2,thumbSize/2); canvas.drawBitmap(thumbBitmap,matrix,null);//旋转背景 } /** * draw lines * @param canvas */ private void drawLine(Canvas canvas){ //绘制背景线 backgroundLineRect.set((getWidth()-backgroundLineSize)/2,thumbSize/2, (getWidth()+backgroundLineSize)/2, getParentHeight()-thumbSize/2); lineSize = getParentHeight() - thumbSize;//去掉被thumb挡住的一部分长度 paint.setColor(Color.rgb(61,82,89)); canvas.drawRoundRect(backgroundLineRect, backgroundLineSize/2, backgroundLineSize/2, paint); //绘制进度线 paint.setColor(Color.rgb(90,189,220));//进度线的颜色 foregroundLineRect.set((getWidth()-foregroundLineSize)/2, (getParentHeight()-thumbSize)*(100-currentDegrees)/100+thumbSize/2, (getWidth()+foregroundLineSize)/2,getParentHeight()-thumbSize/2); canvas.drawRoundRect(foregroundLineRect,foregroundLineSize/2,foregroundLineSize/2,paint); } /** * get ParentHeight * @return */ private int getParentHeight(){ return getHeight(); } @Override public boolean dispatchTouchEvent(MotionEvent event) { return super.dispatchTouchEvent(event); } @Override public boolean onTouchEvent(MotionEvent event) { if (!isEnabled()) return true; switch (event.getAction()) { case MotionEvent.ACTION_DOWN: touchY = event.getRawY();//记录开始的Y值 break; case MotionEvent.ACTION_MOVE: currentDegrees += (touchY-event.getRawY())*1f/(getParentHeight())*100.0f;//当前进度值（100为满） if (currentDegrees > 100){//超出去的不计算，默认为100 currentDegrees = 100; } if (currentDegrees<0){//超出去的不计算，默认为0 currentDegrees = 0; } if (observableEmitter != null){//使用背压发送 observableEmitter.onNext(1); }else {//直接发送 sendProgress(); } touchY = event.getRawY(); invalidate(); break; case MotionEvent.ACTION_CANCEL: break; case MotionEvent.ACTION_UP: break; } return true; } private ObservableEmitter<Integer> observableEmitter; /** *增加背压，防止发射拖动的事件过快,导致内存溢出 */ public void addBackPressure(){ Observable.create(new ObservableOnSubscribe<Integer>() { @Override public void subscribe(ObservableEmitter<Integer> emitter) throws Exception { observableEmitter = emitter; } }).sample(500, TimeUnit.MILLISECONDS) .observeOn(AndroidSchedulers.mainThread()) .subscribe(new Consumer<Integer>() { @Override public void accept(Integer integer) throws Exception { sendProgress(); } }); } /** * 发送进度 */ private void sendProgress(){ if (onProgressListener != null){ onProgressListener.onProgress(currentDegrees); } } /** * 设置当前进度 * @param currentDegrees */ public void setCurrentDegrees(float currentDegrees){ this.currentDegrees = currentDegrees; invalidate(); } public interface OnProgressListener{ void onProgress(float progress); } /** * make a drawable to a bitmap * @param drawable drawable you want convert * @return converted bitmap */ private Bitmap drawableToBitmap(int size, Drawable drawable) { Bitmap bitmap = null; if (drawable instanceof BitmapDrawable) { BitmapDrawable bitmapDrawable = (BitmapDrawable) drawable; bitmap = bitmapDrawable.getBitmap(); if (bitmap != null && bitmap.getHeight() > 0) { Matrix matrix = new Matrix(); float scaleHeight = size * 1.0f / bitmapDrawable.getIntrinsicHeight(); matrix.postScale(scaleHeight, scaleHeight); bitmap = Bitmap.createBitmap(bitmap, 0, 0, bitmap.getWidth(), bitmap.getHeight(), matrix, true); return bitmap; } } bitmap = Bitmap.createBitmap(size, size, Bitmap.Config.ARGB_8888); Canvas canvas = new Canvas(bitmap); drawable.setBounds(0, 0, canvas.getWidth(), canvas.getHeight()); drawable.draw(canvas); return bitmap; } } Demo地址：https://github.com/helang1991/SeekBar 喜欢的就加个Star,谢谢
