1引言
1 精通Android自定义View(一)View的绘制流程简述
2 精通Android自定义View(二)View绘制三部曲
3 精通Android自定义View(三)View绘制三部曲综合简述
4 精通Android自定义View(四)自定义属性使用详解
5 精通Android自定义View(五)自定义属性值使用详情
6 精通Android自定义View(六)绘制篇Paint分析
7 精通Android自定义View(七)绘制篇Canvas分析
8 精通Android自定义View(八)绘制篇Canvas分析绘制文字
9 精通Android自定义View(九)绘制篇Canvas分析绘制图片
10 精通Android自定义View(十)绘制篇Canvas分析之绘制Path
11 精通Android自定义View(十一)绘制篇Canvas分析之裁剪
12 精通Android自定义View(十二)绘制圆形进度条
13 精通Android自定义View(十三)事件分发简述
2 效果图
3 源码
public class HorizontalProgressBar extends ProgressBar {//定义一个画笔protected Paint mPaint = new Paint();//设置默认的显示进度文字的颜色protected int mTextColor = 0xff253688;//设置显示默认的显示进度的文字的大小protected int mTextSize = dp2px(10);//设置默认的绘制进度条的高度protected int mProgressBarHeight = dp2px(10);//设置默认的绘制进度条颜色protected int mBarColor = 0xffffcc00;//未加载进度条的颜色protected int mUnBarColor = 0xffe6e6e6;//绘制进度条的实际宽度private int mMeasureHeight;private int mMeasureWidth;//默认view的宽度private int mDefaultWidth = dp2px(100);private int mDefaultHeight = dp2px(10);private boolean isBackgroundDraw = false;public HorizontalProgressBar(Context context, AttributeSet attrs) {this(context, attrs, 0);}public HorizontalProgressBar(Context context, AttributeSet attrs,int defStyle) {super(context, attrs, defStyle);mPaint.setAntiAlias(true);mPaint.setStrokeJoin(Paint.Join.ROUND);mPaint.setStrokeCap(Paint.Cap.ROUND);mPaint.setTextSize(mTextSize);mPaint.setColor(mTextColor);}@Overrideprotected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {super.onMeasure(widthMeasureSpec, heightMeasureSpec);//测量计算宽度int widthSpecMode = MeasureSpec.getMode(widthMeasureSpec);int widthSpecSize = MeasureSpec.getSize(widthMeasureSpec);if (widthSpecMode == MeasureSpec.EXACTLY) {//当specMode = EXACTLY时，精确值模式，即当我们在布局文件中为View指定了具体的大小mMeasureWidth = widthSpecSize;} else {//指定默认大小mMeasureWidth = mDefaultWidth;if (widthSpecMode == MeasureSpec.AT_MOST) {mMeasureWidth = Math.min(mMeasureWidth, widthSpecSize);}}//测量计算View的高int heightSpecMode = MeasureSpec.getMode(widthMeasureSpec);int heightSpecSize = MeasureSpec.getSize(widthMeasureSpec);if (heightSpecMode == MeasureSpec.EXACTLY) {//当specMode = EXACTLY时，精确值模式，即当我们在布局文件中为View指定了具体的大小mMeasureHeight = heightSpecSize;} else {//指定默认大小mMeasureHeight = mDefaultHeight;if (heightSpecMode == MeasureSpec.AT_MOST) {mMeasureHeight = Math.min(mMeasureHeight, heightSpecSize);}}//重新测量setMeasuredDimension(mMeasureWidth, mMeasureHeight);}@Overrideprotected synchronized void onDraw(Canvas canvas) {canvas.save();//绘制未加载的进度//float start = progressPosTextX + textWidth;float start = 0;mPaint.setColor(mUnBarColor);mPaint.setStrokeWidth(mProgressBarHeight*2);canvas.drawLine(start, 0, mMeasureWidth, 0, mPaint);//定义画笔的初始位置canvas.translate(getPaddingLeft(), getHeight() / 2);//计算加载进度的比例float radio = getProgress() * 1.0f / getMax();// 计算已加载的进度float progressPosTextX = (int) (mMeasureWidth * radio);//定义进度上显示的文字信息String text = getProgress() + "%";//获取绘制文字的宽与高float textWidth = mPaint.measureText(text);float textHeight = (mPaint.descent() + mPaint.ascent()) / 2;//判断绘制float progressPosX=progressPosTextX;if (progressPosTextX + textWidth > mMeasureWidth) {progressPosTextX = mMeasureWidth - textWidth;}//绘制已加载的进度mPaint.setColor(mBarColor);mPaint.setStrokeWidth(mProgressBarHeight);canvas.drawLine(0, 0, progressPosX, 0, mPaint);//绘制加载显示的进度文字mPaint.setColor(mTextColor);canvas.drawText(text, progressPosTextX, -textHeight, mPaint);canvas.restore();}//将设置的db转为屏幕像素protected int dp2px(int dpVal) {return (int) TypedValue.applyDimension(PLEX_UNIT_DIP,dpVal, getResources().getDisplayMetrics());}}
