android球形水波百分比控制項代碼_Android

本文主要介紹的是一個球形水波的百分比控制項，市面上有各種形形色色的百分比控制項，我一直覺得水波是最炫的，UI給了我這個機會，然而網上搜了一大堆，不是太複雜，代碼太多（反正我是調不出效果來），就是有瑕疵的，所以只好自己寫了，這裡開源出來，方便大家。有什麼問題或者建議大家留言指出。

先看效果，這裡動態圖不好截取，就貼張靜態

對於水波百分比控制項實現方法有如下幾種

• - 畫好水波形狀的bitmap，利用屬性動畫進行平移
• - 利用曲線精確繪製目標水波
• - 利用大範圍曲線與容器做交集
  

第一種比較煩，網上有這種思路實現的，代碼量比較龐大。bitmap移動時要注意的問題很多，一不小心就bug一堆了。第二種代碼量小，但需要幾何功底。很丟臉的說我算了好久。才算出公式（年代久遠，都忘了），不過這種方法計算量大，繪製時遍曆的點少。第三種方法，代碼量極少，計算量幾乎沒有，遍曆的點是第二種方法的兩倍以上。考慮到遍曆的消耗和計算的複雜度，選擇第三種。

這裡我們選擇正弦曲線和圓做交集。

 for (int i = left; i < length; i++) {        int x = i;        int y = (int) (Math.sin(Math.toRadians(x + mTranX) / 2) * mRadius / 4);        path2.lineTo(x, mH + y);      }

sin函數，x橫座標，y縱座標，mTranX每次位移量， 波形起伏mRadius / 4，

核心代碼

利用圓的path與我們之前繪製的曲線做交集

Path pc = new Path();      pc.addCircle(mCentrePoint.x, mCentrePoint.y, mRadius, Path.Direction.CCW);      canvas.clipPath(pc, Region.Op.INTERSECT);      canvas.drawPath(path2, mWavePaint);      canvas.restore();

水位上升和水波起伏

while (isDraw) {        if (mWaterLevel > mNowHeight) {          mNowHeight = mNowHeight + mUpSpeed;        }        if (mStart) {          if (mTranX > mRadius) {            mTranX = 0;          }          mTranX = mTranX - mWaveSpeed;        }        drawUI();      }

這裡由於動畫效果比較細膩，更新UI介面比較平凡，所以我們採用surfaceView來實現（用view實現發現有卡頓，影響體驗）

完整代碼

就一個waveview類直接布局中引用

注釋寫的應該算比較清楚了。有什麼疑問的可以留言

package com.aibaide.test;import android.content.Context;import android.graphics.Canvas;import android.graphics.Color;import android.graphics.Paint;import android.graphics.Path;import android.graphics.PixelFormat;import android.graphics.Point;import android.graphics.Region;import android.util.AttributeSet;import android.view.SurfaceHolder;import android.view.SurfaceView;/** * gengqiquan * 2016年6月2日16:16:48 * 水波顯示百分比控制項 */public class WaveView extends SurfaceView implements SurfaceHolder.Callback {  Point mCentrePoint;  int mNowHeight = 0;//當前水位  int mRadius = 0;  boolean mStart = false;//是否開始  float mTextSise = 60;//文字大小  Context mContext;  int mTranX = 0;//水波平移量  private Paint mCirclePaint;  private Paint mOutCirclePaint;  private Paint mWavePaint;  private Paint mTextPaint;  private SurfaceHolder holder;  private RenderThread renderThread;  private boolean isDraw = false;// 控制繪製的開關  private int mCircleColor = Color.parseColor("#ff6600");//背景內圓顏色  private int mOutCircleColor = Color.parseColor("#f5e6dc");//背景外圓顏色  private int mWaveColor = Color.parseColor("#ff944d");//水波顏色  private int mWaterLevel;// 水目標高度  private int flowNum = 60;//水目標佔百分比這裡是整數。  private int mWaveSpeed = 5;//水波起伏速度  private int mUpSpeed = 2;//水面上升速度  /**   * @param context   */  public WaveView(Context context) {    super(context);    // TODO Auto-generated constructor stub    mContext = context;    init(mContext);  }  /**   * @param context   * @param attrs   */  public WaveView(Context context, AttributeSet attrs) {    super(context, attrs);    // TODO Auto-generated constructor stub    mContext = context;    init(mContext);  }  /**   * @param context   * @param attrs   * @param defStyleAttr   */  public WaveView(Context context, AttributeSet attrs, int defStyleAttr) {    super(context, attrs, defStyleAttr);    // TODO Auto-generated constructor stub    mContext = context;    init(mContext);  }  private void init(Context context) {    mContext = context;    setZOrderOnTop(true);    holder = this.getHolder();    holder.addCallback(this);    holder.setFormat(PixelFormat.TRANSLUCENT);    renderThread = new RenderThread();    mCirclePaint = new Paint();    mCirclePaint.setColor(mCircleColor);    mCirclePaint.setStyle(Paint.Style.FILL);    mCirclePaint.setAntiAlias(true);    mOutCirclePaint = new Paint();    mOutCirclePaint.setColor(mOutCircleColor);    mOutCirclePaint.setStyle(Paint.Style.FILL);    mOutCirclePaint.setAntiAlias(true);    mWavePaint = new Paint();    mWavePaint.setStrokeWidth(1.0F);    mWavePaint.setColor(mWaveColor);    mWavePaint.setStyle(Paint.Style.FILL);    mWavePaint.setAntiAlias(true);    mTextPaint = new Paint();    mTextPaint.setStrokeWidth(1.0F);    mTextPaint.setColor(Color.WHITE);    mTextPaint.setTextSize(mTextSise);    mTextPaint.setTextAlign(Paint.Align.CENTER);    mTextPaint.setStyle(Paint.Style.FILL);    mTextPaint.setAntiAlias(true);  }  @Override  public void surfaceChanged(SurfaceHolder holder, int format, int width, int height) {    mRadius = (int) (0.5 * width * 0.92);    mCentrePoint = new Point(width / 2, height / 2);    mWaterLevel = (int) (2 * mRadius * flowNum / 100f);//算出目標水位高度  }  @Override  public void surfaceCreated(SurfaceHolder holder) {    isDraw = true;    if (renderThread != null && !renderThread.isAlive())      renderThread.start();  }  @Override  public void surfaceDestroyed(SurfaceHolder holder) {    isDraw = false;  }  /**   * 繪製介面的線程   *   * @author Administrator   */  private class RenderThread extends Thread {    @Override    public void run() {      // 不停繪製介面，這裡是非同步繪製，不採用外部通知開啟繪製的方式，水波根據資料更新才會開始增長      while (isDraw) {        if (mWaterLevel > mNowHeight) {          mNowHeight = mNowHeight + mUpSpeed;        }        if (mStart) {          if (mTranX > mRadius) {            mTranX = 0;          }          mTranX = mTranX - mWaveSpeed;        }        drawUI();      }      super.run();    }  }  /**   * 介面繪製   */  public void drawUI() {    Canvas canvas = holder.lockCanvas();    try {      drawCanvas(canvas);    } catch (Exception e) {      e.printStackTrace();    } finally {      if (canvas != null)        holder.unlockCanvasAndPost(canvas);    }  }  private void drawCanvas(Canvas canvas) {    //畫背景圓圈    canvas.drawCircle(mCentrePoint.x, mCentrePoint.y, mRadius / 0.92f, mOutCirclePaint);    canvas.drawCircle(mCentrePoint.x, mCentrePoint.y, mRadius, mCirclePaint);    if (mStart) {      //計算正弦曲線的路徑      int mH = mCentrePoint.y + mRadius - mNowHeight;      int left = - mRadius / 2;      int length = 4 * mRadius;      Path path2 = new Path();      path2.moveTo(left, mH);      for (int i = left; i < length; i++) {        int x = i;        int y = (int) (Math.sin(Math.toRadians(x + mTranX) / 2) * mRadius / 4);        path2.lineTo(x, mH + y);      }      path2.lineTo(length, mH);      path2.lineTo(length, mCentrePoint.y + mRadius);      path2.lineTo(0, mCentrePoint.y + mRadius);      path2.lineTo(0, mH);      canvas.save();      //這裡與圓形取交集，除去正弦曲線多畫的部分      Path pc = new Path();      pc.addCircle(mCentrePoint.x, mCentrePoint.y, mRadius, Path.Direction.CCW);      canvas.clipPath(pc, Region.Op.INTERSECT);      canvas.drawPath(path2, mWavePaint);      canvas.restore();      //繪製文字      canvas.drawText(flowNum + "%", mCentrePoint.x, mCentrePoint.y, mTextPaint);    }  }  public void setFlowNum(int num) {    flowNum = num;    mStart = true;  }  public void setTextSise(float s) {    mTextSise = s;    mTextPaint.setTextSize(s);  }  //設定水波起伏速度  public void setWaveSpeed(int speed) {    mWaveSpeed = speed;  }  //設定水面上升速度  public void setUpSpeed(int speed) {    mUpSpeed = speed;  }  public void setColor(int waveColor, int circleColor, int outcircleColor) {    mWaveColor = waveColor;    mCircleColor = circleColor;    mOutCircleColor = outcircleColor;    mWavePaint.setColor(mWaveColor);    mCirclePaint.setColor(mCircleColor);    mOutCirclePaint.setColor(mOutCircleColor);  }//精確演算法，每次正弦曲線從曲線與圓的交集處開始//  private int getX(double h) {//    int x = 0;//    int R = mRadius;//    if (h < R) {//      double t = 2 * R * h - h * h;//      x = (int) (R - Math.abs(Math.sqrt(t)));//    } else {//      double t = -2 * R * h + h * h;//      x = (int) (R - Math.abs(Math.sqrt(t)));//    }//    return x;//  }}

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