android实现环形进度条

package cn.zyt.widgets;

import android.content.Context;
import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.Paint;
import android.graphics.Paint.Style;
import android.graphics.RectF;
import android.util.AttributeSet;
import android.view.View;
import cn.likeit.solar.R;

public class CircleProgressBar extends View {
private int maxProgress = 100;
private int progress = 95;
private int progressStrokeWidth = 4;
// 画圆所在的距形区域
RectF oval;
Paint paint;
public CircleProgressBar(Context context, AttributeSet attrs) {
super(context, attrs);
oval = new RectF();
paint = new Paint();
}

@Override
protected void onDraw(Canvas canvas) {
super.onDraw(canvas);
int width = this.getWidth();
int height = this.getHeight();
if (width != height) {
int min = Math.min(width, height);
width = min;
height = min;
}
canvas.drawColor(Color.TRANSPARENT); // 白色背景
paint.setAntiAlias(true); // 设置画笔为抗锯齿
paint.setColor(Color.parseColor("#f0f0f0")); // 设置画笔颜色
paint.setStrokeWidth(progressStrokeWidth * 3); // 线宽
paint.setStyle(Style.STROKE);
// 线中心与四周的距离
oval.left = progressStrokeWidth * 1.5f; // 左上角x
oval.top = progressStrokeWidth * 1.5f; // 左上角y
oval.right = width - progressStrokeWidth * 1.5f; // 左下角x
oval.bottom = height - progressStrokeWidth * 1.5f; // 右下角y

canvas.drawArc(oval, -90, 360, false, paint); // 绘制白色圆圈，即进度条背景

paint.setColor(Color.parseColor("#238f31"));
paint.setStrokeWidth(progressStrokeWidth);

oval.left = progressStrokeWidth * 1.5f; // 左上角x
oval.top = progressStrokeWidth * 1.5f; // 左上角y
oval.right = width - progressStrokeWidth * 1.5f; // 左下角x
oval.bottom = height - progressStrokeWidth * 1.5f; // 右下角y

canvas.drawArc(oval, -90, ((float) progress / maxProgress) * 360,
false, paint); // 绘制进度圆弧，这里是蓝色

String text = progress + "%";
int textHeight = height / 4;
paint.setStrokeWidth(1);
paint.setTextSize(textHeight);
paint.setColor(Color.parseColor("#969696"));
int textWidth = (int) paint.measureText(text, 0, text.length());
paint.setStyle(Style.FILL);
canvas.drawText(text, width / 2 - textWidth / 2, height / 2, paint);

String status = getResources().getString(R.string.smu_status);
textHeight = height / 6;
paint.setColor(Color.parseColor("#c8c8c8"));
paint.setTextSize(textHeight);
textWidth = (int) paint.measureText(status, 0, status.length());
canvas.drawText(status, width / 2 - textWidth / 2, height / 2
+ textHeight * 4 / 3, paint);

}

public int getMaxProgress() {
return maxProgress;
}

public void setMaxProgress(int maxProgress) {
this.maxProgress = maxProgress;
}

public void setProgress(int progress) {
this.progress = progress;
this.invalidate();
}

/**
* 非UI线程调用，setProgress方法只能在UI线程种进行工作，若是其他线程则调用此方法更新状态。
*/
public void setProgressNotInUiThread(int progress) {
this.progress = progress;
this.postInvalidate();
}
}