Android自定义控件实现带文本与数字的圆形进度条

anvas.clipRect(0, 0, mWidth, mHeight / 2 + radius - textHeight * 3 / 4);

final CustomCircleBar circle=(CustomCircleBar)findViewById(R.id.win_home);circle.setPercent(10);circle.setCustomText("呵呵");circle.setProgessColor(getResources().getColor(R.color.blue));final Random random=new Random();circle.setOnClickListener(new View.OnClickListener(){ @Override public void onClick(View v){ circle.setPercent(random.nextInt(100)); }});

public class CustomCircleBar extends View { private Context context; /** * 进度值 */ private int percent; /** * 颜色值 */ private int mProgessColor; /** * 下边的文字名称 */ private String mCustomText; /** * 外圈圆环的画笔 */ private Paint paintBar = new Paint(); /** * 下边文字的画笔 */ private Paint paintText = new Paint(); /** * 动态获取属性值 */ private TypedValue typedValue; /** * 先加速后减速 */ DecelerateInterpolator mDecelerateInterpolator = new DecelerateInterpolator(); /** * 动画持续时间 */ private int duration = 10; private int curTime = 0; public CustomCircleBar(Context context) { super(context); this.context=context; init(); }  public CustomCircleBar(Context context, AttributeSet attrs) { super(context, attrs); this.context=context; init(); }  public CustomCircleBar(Context context, AttributeSet attrs, int defStyleAttr) { super(context, attrs, defStyleAttr); this.context=context; init(); }    public void setPercent(int percent) { this.percent = percent; /*isShown()：Returns the visibility of this view and all of its ancestors*/ if (isShown()) {  /**  * 设置进度后重新开始一次动画  */  curTime=0;  this.invalidate(); } }  public void setProgessColor(int mProgessColor) { this.mProgessColor = mProgessColor; if (isShown()) {  this.invalidate(); } }   public void setCustomText(String mCustomText) { this.mCustomText = mCustomText; }  private Handler mHandler = new Handler(); private Runnable mAnimation = new Runnable() { @Override public void run() {  if (curTime < duration) {  curTime++;  /** 导致重绘，调用onDraw，onDraw最后调用   * mHandler.postDelayed(mAnimation, 20);更新进度条，界面重绘   * 每次20毫秒，绘制10次，因此动画时间200毫秒   */  CustomCircleBar.this.invalidate();  } } };  private void init() { /**  * 数据初始化，没有设置属性时候的默认值  */ percent = 0; mProgessColor=Color.rgb(95,112,72); mCustomText="Home"; typedValue=new TypedValue(); context.getTheme().resolveAttribute(R.attr.maintextclor,typedValue,true); }    @Override protected void onDraw(Canvas canvas) { super.onDraw(canvas); float mWidth = getWidth(); float mHeight = getHeight(); /**  * 下边是进度条画笔的设置  */ /** Restores the paint to its default settings. */ paintBar.reset(); /**  * 圆环宽度4个像素  */ paintBar.setStrokeWidth(4); /**  * 空心圆环而非填充的额扇形  */ paintBar.setStyle(Paint.Style.STROKE); paintBar.setAntiAlias(true); paintBar.setColor(mProgessColor); /**  * 调整下不透明度，使边框弧和进度条区分开  */ paintBar.setAlpha(80); /**  * 接下来是文字画笔的设置  */ paintText.setTextSize(20); paintText.setColor(getResources().getColor(typedValue.resourceId)); paintText.setStyle(Paint.Style.STROKE); paintText.setAntiAlias(true); /**  * 从中间开始绘制文本  */ paintText.setTextAlign(Paint.Align.CENTER); /**  * 测量文字大小  */ Paint.FontMetrics fontMetrics = paintText.getFontMetrics(); /**  * 计算文字高度  */ float textHeight = fontMetrics.bottom - fontMetrics.top; /**  * 计算圆的半径  */ float radius = Math.min(mWidth, mHeight) / 2 - 10; /* ❑ save：用来保存Canvas的状态。save之后，可以调用Canvas的平移、放缩、旋转、错切、裁剪等操作。  ❑ restore：用来恢复Canvas之前保存的状态。防止save后对Canvas执行的操作对后续的绘制有影响。*/ /*保存画布，绘制进度条*/ canvas.save(); /*clipRect：该方法用于裁剪画布，也就是设置画布的显示区域 调用clipRect()方法后，只会显示被裁剪的区域，之外的区域将不会显示 */ canvas.clipRect(0, 0, mWidth, mHeight / 2 + radius - textHeight * 3 / 4); /*因为clipRect的原因，外边的圆环下边留个缺口绘制文字*/ canvas.drawCircle(mWidth / 2, mHeight / 2, radius, paintBar);  /**  * 三角函数计算，下方缺口扇形的角度的一半  */ float theta_offset = (float) Math.acos((radius - textHeight / 2) / radius); /**  * 大弧围成的扇形的角度  */ float theta_full = 360 - 2 * theta_offset; /**  * 进度值围成的弧对应的角度  */ float thetaProcess = mDecelerateInterpolator.getInterpolation(1.0f * curTime / duration) * percent * theta_full / 100; /**  * 设置进度值颜色完全不透明  */ paintBar.setAlpha(255); paintBar.setColor(mProgessColor); /**  * 注意弧形的起始角度，下边因显示文字导致圆环断开成一条弧，弧有左右两个端点，从左端点开始画弧  */ canvas.drawArc(new RectF(mWidth / 2 - radius, mHeight / 2 - radius, mWidth / 2 + radius, mHeight / 2 + radius), theta_offset+90, thetaProcess, false, paintBar); /**  * 恢复画布  */ canvas.restore(); /**  * 开始绘制文字  */ paintText.setTextSize(20); fontMetrics = paintText.getFontMetrics(); float textBaseLineOffset = (fontMetrics.bottom - fontMetrics.top) / 2 - fontMetrics.bottom; canvas.drawText(mCustomText, mWidth / 2, mHeight / 2 + radius - textHeight / 2 + textBaseLineOffset, paintText);  /**  * 绘制百分号  */ paintText.setTextSize(mHeight * 1 / 8); fontMetrics = paintText.getFontMetrics(); textBaseLineOffset = (fontMetrics.bottom - fontMetrics.top) / 2 - fontMetrics.bottom; canvas.drawText("%", mWidth / 2, mHeight / 2 + radius / 3 + textBaseLineOffset, paintText);  /**  * 绘制百分比  */ paintText.setTextSize(mHeight * 3 / 8); canvas.drawText("" + (int)(percent*mDecelerateInterpolator.getInterpolation(1.0f * curTime / duration)), mWidth / 2, mHeight / 2, paintText); /**  * 20毫秒后执行动画  */ mHandler.postDelayed(mAnimation, 20); }}