Android渐变色水波纹效果
化作孤岛的瓜 人气:0项目中使用到的效果,效果图如下:
代码实现:
public class WaveView extends View { private Paint mPaint, mCriclePaint, mTextPaint; // 倾斜或旋转、快速变化,当在屏幕上画一条直线时, 横竖不会出现锯齿, // 但是当斜着画时, 就会出现锯齿的效果,所以需要设置抗锯齿 private DrawFilter mDrawFilter; private int mTotalHeight, mTotalWidth; private int mXoffset = 0; private float[] mPointY; private float[] mDaymicPointY; private int currentIndex = 1; private int currentColor=0xaa3bb6e7; //波浪线移动速度 private static final int X_SPEED = 20; private int percent; public void setPercent(int percent) { this.percent = percent; } public WaveView(Context context) { super(context); init(); } public int getCurrentIndex() { return currentIndex; } public void setCurrentIndex(int currentIndex) { this.currentIndex = currentIndex; if (currentIndex==1){ currentColor = 0xaa3bb6e7; }else if(currentIndex==2){ currentColor = 0xaa3c3c3c; }else if (currentIndex==3){ currentColor = 0xaa724527; } } public WaveView(Context context, AttributeSet attrs) { super(context, attrs); init(); } public WaveView(Context context, AttributeSet attrs, int defStyleAttr) { super(context, attrs, defStyleAttr); init(); } private void init() { //图片线条(通用)的抗锯齿需要另外设置 mDrawFilter = new PaintFlagsDrawFilter(0, Paint.ANTI_ALIAS_FLAG | Paint.FILTER_BITMAP_FLAG); //实例化一个画笔 mPaint = new Paint(); //去除画笔锯齿 mPaint.setAntiAlias(true); //设置画笔风格为实线 mPaint.setStyle(Paint.Style.FILL); //设置画笔颜色 mPaint.setColor(Color.GREEN); //实例化圆的画笔 mCriclePaint = new Paint(mPaint); mCriclePaint.setColor(Color.parseColor("#88dddddd")); mCriclePaint.setAlpha(255); //实例化文字画笔 mTextPaint = new Paint(); mTextPaint.setAntiAlias(true); } LinearGradient linearGradient; @Override protected void onDraw(Canvas canvas) { super.onDraw(canvas); //去除锯齿 canvas.setDrawFilter(mDrawFilter); runWave(); int canvasWidth = canvas.getWidth(); int canvasHeight = canvas.getHeight(); int layerId = canvas.saveLayer(0, 0, canvasWidth, canvasHeight, null, Canvas.ALL_SAVE_FLAG); // canvas.drawCircle(mTotalWidth / 2, mTotalHeight / 2, mTotalWidth / 2, mCriclePaint); //设置颜色混合模式 // mPaint.setXfermode(new PorterDuffXfermode(PorterDuff.Mode.SRC_IN)); //高减去宽除以2使水波纹底部在圆底部,动态改变percent值,在Y轴上变化 //画进度条 //aa3c3c3c //aa724527 final int c = currentColor; int colorSweep[] = {c,Color.TRANSPARENT}; //设置渐变色 linearGradient = new LinearGradient(0, mTotalHeight-percent*mTotalHeight/100-80,0,mTotalHeight, colorSweep, null, Shader.TileMode.MIRROR); mPaint.setShader(linearGradient); for (int i = 0; i < mTotalWidth; i++) { canvas.drawLine(i, mTotalHeight - mDaymicPointY[i] - (mTotalHeight - mTotalWidth) / 2 - percent * mTotalWidth / 100, i, mTotalHeight - (mTotalHeight - mTotalWidth) / 2, mPaint); } // RoundLightBarView //最后将画笔去除Xfermode // mPaint.setXfermode(null); canvas.restoreToCount(layerId); //改变两条波纹的移动点 mXoffset += X_SPEED; //如果已经移动到末尾处,则到头重新移动 if (mXoffset > mTotalWidth) { mXoffset = 0; } String text = percent + " "; mTextPaint.setColor(Color.WHITE); mTextPaint.setTextSize(180); float textLength = mTextPaint.measureText(text); int textY = mTotalHeight - percent * mTotalHeight / 100; if (textY < 180) { textY = 180; } if (textY > mTotalHeight - 80) { textY = mTotalHeight - 80; } canvas.drawText(text, (mTotalWidth - textLength) / 2, textY, mTextPaint); mTextPaint.setTextSize(90); String aText = percent < 10 ? " %" : percent < 100 ? " %" : " %"; //4 9 13 canvas.drawText(aText, (mTotalWidth - textLength) / 2, textY, mTextPaint); // LogUtils.d("totalWdith:"+mTotalWidth+"---totalH:"+mTotalHeight); //引起view重绘 postInvalidateDelayed(300); } @Override protected void onSizeChanged(int w, int h, int oldw, int oldh) { super.onSizeChanged(w, h, oldw, oldh); mTotalHeight = h; mTotalWidth = w; //数组的长度为view的宽度 mPointY = new float[w]; mDaymicPointY = new float[w]; //这里我们以view的总宽度为周期,y = a * sin(2π) + b for (int i = 0; i < mTotalWidth; i++) { mPointY[i] = (float) (20 * (Math.sin(2 * Math.PI * i / w))); } } private void runWave() { // 超出屏幕的挪到前面,mXoffset表示第一条水波纹要移动的距离 int yIntelrval = mPointY.length - mXoffset; //使用System.arraycopy方式重新填充第一条波纹的数据 System.arraycopy(mPointY, 0, mDaymicPointY, mXoffset, yIntelrval); System.arraycopy(mPointY, yIntelrval, mDaymicPointY, 0, mXoffset); } }
实现原理:
1、首先波浪的绘制是很多个竖直的线,并通过正弦坐标转换坐标实现。
2、渐变色通过设置画笔LinearGradient实现。
加载全部内容