android自定义view实现数字进度条

 package com.tuya; import android.animation.ValueAnimator; import android.content.Context; import android.graphics.Canvas; import android.graphics.Color; import android.graphics.Paint; import android.graphics.Rect; import android.util.AttributeSet; import android.view.View; /** * Created by admin on 2016/12/19. */ public class DownLoadProgressView extends View { private Paint paint;//绘制进度条画笔 private Paint textPaint;//绘制文字画笔 private Paint dottePaint;//绘制灰色线画笔 private int width; private int height; private int padding =5; private int value = 0; public DownLoadProgressView(Context context) { this(context,null); } public DownLoadProgressView(Context context, AttributeSet attrs) { this(context, attrs,0); } public DownLoadProgressView(Context context, AttributeSet attrs, int defStyleAttr) { super(context, attrs, defStyleAttr); initPaint(); } @Override protected void onSizeChanged(int w, int h, int oldw, int oldh) { super.onSizeChanged(w, h, oldw, oldh); width = w; height = h; } /** * 初始化画笔 */ private void initPaint() { paint = new Paint(); paint.setAntiAlias(true); paint.setStrokeWidth(2); paint.setStyle(Paint.Style.FILL); paint.setColor(Color.BLUE); textPaint = new Paint(); textPaint.setAntiAlias(true); textPaint.setStrokeWidth(3); textPaint.setStyle(Paint.Style.FILL); textPaint.setColor(Color.BLUE); textPaint.setTextSize(12); dottePaint = new Paint(); dottePaint.setAntiAlias(true); dottePaint.setStrokeWidth(2); dottePaint.setStyle(Paint.Style.FILL); dottePaint.setColor(Color.parseColor("#e5e5e5")); } @Override protected void onDraw(Canvas canvas) { super.onDraw(canvas); String str = value+"%"; float strWidth = textPaint.measureText(value+"%")+padding;//绘制文字的宽度 +padding是为了防止在进度条加载完毕的时候文字绘制出现被切掉情况 Rect rect = new Rect(); textPaint.getTextBounds(str,0,str.length(),rect); canvas.drawLine(0,height/2,value*((width-strWidth)/100),height/2,paint);//绘制进度 canvas.drawText(value+"%",value*((width-strWidth)/100)+padding,(height-rect.height())/2+2*padding,textPaint);//绘制进度文字 这个高度+2*padding是因为drawText是根据基线计算的,要准确的话要去求基线 canvas.drawLine(value*((width-strWidth)/100)+strWidth+padding,height/2,width,height/2,dottePaint);//绘制灰色进度表示剩余多少 postDelayed(new Runnable() { @Override public void run() { if(value<100){ value++; postInvalidate(); } } },100); } }