项目开发即时通讯发送小视频功能，就想着要做一个跟微信那样的下载进度圆
效果图
自定义View：
import android.content.Context;
import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.Paint;
import android.graphics.RectF;
import android.os.Build;
import android.util.AttributeSet;
import android.view.View;
/**
* 作者：wangjian
* 时间：2018/4/8 10:04
* 作用：用于小视频加载进度圆
*/
public class LoadingCircleView extends View {
private PaintpaintBgCircle; //背景圆
private PaintpaintCircle; //填充圆
private PaintpaintProgressCircle; //进度圆
private float startAngle = -90f; //开始角度
private float sweepAngle =0; //进度角度
private int progressCirclePadding =0; //进度圆与背景圆的间距
private boolean fillIn =false; //进度圆是否填充
public LoadingCircleView(Context context) {
super(context);
init();
}
public LoadingCircleView(Context context, AttributeSet attrs) {
super(context, attrs);
init();
}
public LoadingCircleView(Context context, AttributeSet attrs, int defStyleAttr) {
super(context, attrs, defStyleAttr);
init();
}
public LoadingCircleView(Context context, AttributeSet attrs, int defStyleAttr, int defStyleRes) {
super(context, attrs, defStyleAttr, defStyleRes);
init();
}
private void init() {
progressCirclePadding = dip2px(getContext(), 3);
paintBgCircle =new Paint();
paintBgCircle.setAntiAlias(true);
paintBgCircle.setStyle(Paint.Style.FILL);
paintBgCircle.setColor(Color.WHITE);
paintCircle =new Paint();
paintCircle.setAntiAlias(true);
paintCircle.setStyle(Paint.Style.FILL);
paintCircle.setColor(Color.BLACK);
paintProgressCircle =new Paint();
paintProgressCircle.setAntiAlias(true);
paintProgressCircle.setStyle(Paint.Style.FILL);
paintProgressCircle.setColor(Color.WHITE);
}
@Override
protected void onDraw(Canvas canvas) {
super.onDraw(canvas);
canvas.drawCircle(
getMeasuredWidth() /2,
getMeasuredWidth() /2,
getMeasuredWidth() /2,
paintBgCircle);
canvas.drawCircle(
getMeasuredWidth() /2,
getMeasuredWidth() /2,
getMeasuredWidth() /2 -progressCirclePadding /2,
paintCircle);
RectF rf =new RectF(
progressCirclePadding,
progressCirclePadding,
getMeasuredWidth() -progressCirclePadding,
getMeasuredWidth() -progressCirclePadding);
canvas.drawArc(
rf,
startAngle,
sweepAngle,
true,
paintProgressCircle);
if (!fillIn) {
canvas.drawCircle(
getMeasuredWidth() /2,
getMeasuredWidth() /2,
getMeasuredWidth() /2 -progressCirclePadding *2,
paintCircle);
}
}
public void startAnimAutomatic(boolean fillIn) {
setProgress(0, fillIn);
}
public void setProgress(int progress, boolean fillIn) {
this.fillIn = fillIn;
sweepAngle = (float) (360 /100.0 * progress);
invalidate();
}
public int dip2px(Context context, float dpValue) {
final float scale = context.getResources().getDisplayMetrics().density;
return (int) (dpValue * scale +0.5f);
}
}
有了自定义View，需要在点击下载的时候把 view给显示出来，然后在下载的线程的回调中使用自定义view的
setProgress(progress, fillIn)方法，progress是文件下载的进度，fillIn是绘制的进度圆是否填充
计算文件下载进度方式请参考我的另一篇文章 Android使用HttpGet下载文件计算下载进度
