ZoomBar 设计

 package com.example.canvasdemo;

 import android.content.Context;

 import android.graphics.Canvas;

 import android.graphics.Color;

 import android.graphics.EmbossMaskFilter;

 import android.graphics.Paint;

 import android.graphics.SweepGradient;

 import android.util.AttributeSet;

 import android.view.View;

 /**

  *

  * @author liemng  QQ:859686819

  *

  */

 public class ZoomPinch extends View{

     private Paint mLinePaint;

     private Paint mPointPaint;

     private int mLineWitdh = 18;

     private int mPointPaintWitdh = 12;

     private String mForeground = "#FFFFFF";

     private String mBackground = "#ff0000";

     // 梯度渐变的填充颜色

     private int[] arcColors = new int[] { 0xFF48cbdc, 0xFF4c9fda, 0xFFeac83d,

             0xFFc7427e, 0xFF48cbdc, 0xFF48cbdc };

     public ZoomPinch(Context context, AttributeSet attrs, int defStyleAttr) {

         super(context, attrs, defStyleAttr);

         initData();

     }

     public ZoomPinch(Context context, AttributeSet attrs) {

         this(context, attrs, 0);

     }

     public ZoomPinch(Context context) {

         this(context, null);

     }

     public void initData(){

         //--绘制线段画笔

         mLinePaint = new Paint();

         //--抗锯齿

         mLinePaint.setAntiAlias(true);

         //--防抖

         mLinePaint.setDither(true);

         //--线段两端的形状

         mLinePaint.setStrokeCap(Paint.Cap.ROUND);

         // 线段的宽度

         mLinePaint.setStrokeWidth(mLineWitdh);

         //--画笔颜色

         mLinePaint.setColor(Color.parseColor("#000000"));

         //--设置光源的方向

         float[] direction = new float[]{ 1, 1, 1 };

         //--设置环境光亮度

         float light = 0.4f;

         //--选择要应用的反射等级

         float specular = 6;

         //--向mask应用一定级别的模糊

         float blur = 3.5f;

         EmbossMaskFilter emboss=new EmbossMaskFilter(direction,light,specular,blur);

         mLinePaint.setMaskFilter(emboss);

         //--绘制圆环的画笔

         mPointPaint = new Paint();

         //--抗锯齿

         mPointPaint.setAntiAlias(true);

         //--防抖

         mPointPaint.setDither(true);

         //--线段两端的形状

         mPointPaint.setStrokeCap(Paint.Cap.ROUND);

         //--线段的宽度

         mPointPaint.setStrokeWidth(mPointPaintWitdh);

         //--画笔颜色

         SweepGradient  mSweepGradient = new SweepGradient(mH/2, mW/2, arcColors, null);

         mPointPaint.setShader(mSweepGradient);

     }

     private int mH ;

     private int mW ;

     private int mMaxHight = 500;

     private int topsurplus = mLineWitdh/2 + 10;

     private int mProgres = 0;

     private float mTotalProgress = mMaxHight;

     private int inCircleR = 6;

     private int outCircleR = 14;

     private int currentLineProgress = 0;

     @Override

     protected void onSizeChanged(int w, int h, int oldw, int oldh) {

         // TODO Auto-generated method stub

         super.onSizeChanged(w, h, oldw, oldh);

         mH = w;

         mW = h;

     }

     @Override

     protected void onDraw(Canvas canvas) {

         // TODO Auto-generated method stub

         super.onDraw(canvas);

         //--平移画布

         canvas.translate(0, topsurplus);

         //--绘制背景色

         mLinePaint.setColor(Color.parseColor(mBackground));

         canvas.drawLine(mW/2, mMaxHight, mW/2, 0, mLinePaint);

         //--绘制前景色

         mLinePaint.setColor(Color.parseColor(mForeground));

         canvas.drawLine(mW/2, mMaxHight, mW/2, mMaxHight - currentLineProgress, mLinePaint);

         //--绘制圆环

         mPointPaint.setStyle(Paint.Style.STROKE);

         canvas.drawCircle(mW/2, mMaxHight - currentLineProgress , outCircleR, mPointPaint);

         mPointPaint.setStyle(Paint.Style.FILL);

         canvas.drawCircle(mW/2, mMaxHight - currentLineProgress , inCircleR, mPointPaint);

     }

     public void setBackgroup(String mBackgroup){

         this.mBackground = mBackgroup;

     }

     public void setForeground(String mForeground){

         this.mForeground = mForeground;

     }

     public void setProgress(float mProgress){

         if(this.mProgres >= mTotalProgress && mProgress > 0)

             return;

         this.mProgres += mProgress;

         float percent = mProgres/mTotalProgress;

         if(percent <0){

             this.mProgres = 0;

             return;

         }

         this.currentLineProgress = (int) (percent*mMaxHight);

         invalidate();

     }

     public void setMax(float mTotalProgress){

         if(mTotalProgress < 0)

             new IllegalArgumentException("invalid args && doubi");

         this.mTotalProgress = mTotalProgress;

     }

 }

效果图如下：

左侧增加文字属性：

package com.example.canvasdemo;

import android.content.Context;

import android.graphics.Canvas;

import android.graphics.Color;

import android.graphics.EmbossMaskFilter;

import android.graphics.Paint;

import android.graphics.Paint.FontMetrics;

import android.graphics.SweepGradient;

import android.util.AttributeSet;

import android.view.View;

/**

 *

 * @author liemng  QQ:859686819

 *

 */

public class ZoomPinch extends View{

	private Paint mLinePaint;

	private Paint mPointPaint;

	private int mLineWitdh = 18;

	private int mPointPaintWitdh = 12;

	private String mForeground = "#FFFFFF";

	private String mBackground = "#ff0000";

	private String[] mTips = new String[]{"1.0X", "2.0X", "3.0X", "4.0X"};

	// 梯度渐变的填充颜色

	private int[] arcColors = new int[] { 0xFF48cbdc, 0xFF4c9fda, 0xFFeac83d,

			0xFFc7427e, 0xFF48cbdc, 0xFF48cbdc };

	public ZoomPinch(Context context, AttributeSet attrs, int defStyleAttr) {

		super(context, attrs, defStyleAttr);

		initData();

	}

	public ZoomPinch(Context context, AttributeSet attrs) {

		this(context, attrs, 0);

	}

	public ZoomPinch(Context context) {

		this(context, null);

	}

	public void initData(){

		//--绘制线段画笔

		mLinePaint = new Paint();

		//--抗锯齿

		mLinePaint.setAntiAlias(true);

		//--防抖

		mLinePaint.setDither(true);

		//--线段两端的形状

		mLinePaint.setStrokeCap(Paint.Cap.ROUND);

		// 线段的宽度

		mLinePaint.setStrokeWidth(mLineWitdh);

		//--画笔颜色

		mLinePaint.setColor(Color.parseColor("#000000"));

		//--设置光源的方向

		float[] direction = new float[]{ 1, 1, 1 };

		//--设置环境光亮度

		float light = 0.4f;

		//--选择要应用的反射等级

		float specular = 6;

		//--向mask应用一定级别的模糊

		float blur = 3.5f;

		EmbossMaskFilter emboss=new EmbossMaskFilter(direction,light,specular,blur);

		mLinePaint.setMaskFilter(emboss);

		//--绘制圆环的画笔

		mPointPaint = new Paint();

		//--抗锯齿

		mPointPaint.setAntiAlias(true);

		//--防抖

		mPointPaint.setDither(true);

		//--线段两端的形状

		mPointPaint.setStrokeCap(Paint.Cap.ROUND);

		//--线段的宽度

		mPointPaint.setStrokeWidth(mPointPaintWitdh);

		//--画笔颜色

		SweepGradient  mSweepGradient = new SweepGradient(mH/2, mW/2, arcColors, null);

		mPointPaint.setShader(mSweepGradient);

		mTextPaint = new Paint();

		mTextPaint.setTextSize(32);

		mTextPaint.setColor(Color.parseColor("#FFFFFF"));

	}

	private int averH;

	private int mH ;

	private int mW ;

	private int mMaxHight = 500;

	private int topsurplus = mLineWitdh/2 + 10;

	private int mProgres = 0;

	private float mTotalProgress = mMaxHight;

	private int inCircleR = 6;

	private int outCircleR = 14;

	private int currentLineProgress = 0;

	private Paint mTextPaint;

	@Override

	protected void onSizeChanged(int w, int h, int oldw, int oldh) {

		super.onSizeChanged(w, h, oldw, oldh);

		mH = w;

		mW = h;

	}

	@Override

	protected void onDraw(Canvas canvas) {

		super.onDraw(canvas);

		//--平移画布

		canvas.translate(0, topsurplus);

		//--绘制背景色

		mLinePaint.setColor(Color.parseColor(mBackground));

		canvas.drawLine(mW/2, mMaxHight, mW/2, 0, mLinePaint);

		//--绘制前景色

		mLinePaint.setColor(Color.parseColor(mForeground));

		canvas.drawLine(mW/2, mMaxHight, mW/2, mMaxHight - currentLineProgress, mLinePaint);

		//--绘制圆环

		mPointPaint.setStyle(Paint.Style.STROKE);

		canvas.drawCircle(mW/2, mMaxHight - currentLineProgress , outCircleR, mPointPaint);

		mPointPaint.setStyle(Paint.Style.FILL);

		canvas.drawCircle(mW/2, mMaxHight - currentLineProgress , inCircleR, mPointPaint);

		//--绘制左侧文字

		for (int i = 0; i < mTips.length; i++) {

			float textW = mTextPaint.measureText(mTips[i]);

			FontMetrics fontMetrics = mTextPaint.getFontMetrics();

			int textH = (int) (fontMetrics.descent - fontMetrics.ascent);

			if(i == 0){

				canvas.drawText(mTips[i], mW/2 - textW*3/2, mMaxHight, mTextPaint);

				continue;

			}

			if(i == (mTips.length -1)){

				canvas.drawText(mTips[i], mW/2 - textW*3/2, topsurplus, mTextPaint);

				continue;

			}

			averH = mMaxHight/(mTips.length -1);

			canvas.drawText(mTips[i], mW/2 - textW*3/2, mMaxHight - topsurplus - (averH*i - textH/2) , mTextPaint);

		}

	}

	public void setBackgroup(String mBackgroup){

		this.mBackground = mBackgroup;

	}

	public void setForeground(String mForeground){

		this.mForeground = mForeground;

	}

	public void setProgress(float mProgress){

		if(this.mProgres >= mTotalProgress && mProgress > 0)

			return;

		this.mProgres += mProgress;

		float percent = mProgres/mTotalProgress;

		if(percent <0){

			this.mProgres = 0;

			return;

		}

		this.currentLineProgress = (int) (percent*mMaxHight);

		invalidate();

	}

	public void setMax(float mTotalProgress){

		if(mTotalProgress < 0)

			new IllegalArgumentException("invalid args && doubi");

		this.mTotalProgress = mTotalProgress;

	}

}

效果图如下：