package com.netease.nim.uikit.common.ui.ptr2;
import android.content.Context;
import android.content.res.TypedArray;
import android.graphics.Canvas;
import android.graphics.Paint;
import android.graphics.Path;
import android.graphics.PointF;
import android.util.AttributeSet;
import android.view.View;
import com.netease.nim.uikit.R;
import com.netease.nim.uikit.common.util.sys.ScreenUtil;
/**
* Created by sunpingji.
*/
public class LoadingView extends View {
private static final float DEFAULT_RADIUS = ScreenUtil.dip2px(5);
private static final int DEFAULT_BALL_COLOR = 0xffffffff;
private static final float DEFAULT_SPEED = (float) 0.5;
private Paint paint = new Paint();
private Paint paint2 = new Paint();
private PointF leftBall;
private PointF rightBall;
//两个小球的碰撞参数
private float handleLenRate = 1f;
private float radius = DEFAULT_RADIUS;
private float mv = 0.5f;
private float maxTouchDistance = (float) (DEFAULT_RADIUS * 2.5);
private int ballLeftColor = DEFAULT_BALL_COLOR;
private int ballRightColor = DEFAULT_BALL_COLOR;
//两个小球动画距离
private float ballMoveDistance = (float) (DEFAULT_RADIUS * 3.5);
//默认1秒 speed = 1/time;故speed=0.5表示2秒结束动画
private float animationSpeed = DEFAULT_SPEED;
private float baseX;
private float baseY;
private boolean isNeedAnimation;
public LoadingView(Context context) {
this(context, null);
}
public LoadingView(Context context, AttributeSet attrs) {
this(context, attrs, 0);
}
public LoadingView(Context context, AttributeSet attrs, int defStyleAttr) {
super(context, attrs, defStyleAttr);
init(attrs);
}
public void reset() {
if (leftBall != null && rightBall != null) {
leftBall.x = baseX;
rightBall.x = baseX;
}
}
public void setPaintMode(int mode) {
paint.setStyle(mode == 0 ? Paint.Style.STROKE : Paint.Style.FILL);
paint2.setStyle(mode == 0 ? Paint.Style.STROKE : Paint.Style.FILL);
invalidate();
leftBall.x = rightBall.x;
}
private void init(AttributeSet attrs) {
TypedArray a = getContext().obtainStyledAttributes(attrs, R.styleable.LoadingView);
ballLeftColor = a.getColor(R.styleable.LoadingView_left_ball_color, DEFAULT_BALL_COLOR);
ballRightColor = a.getColor(R.styleable.LoadingView_right_ball_color, DEFAULT_BALL_COLOR);
radius = a.getFloat(R.styleable.LoadingView_radius, DEFAULT_RADIUS);
maxTouchDistance = (float) (radius * 2.5);
ballMoveDistance = (float) (radius * 3.5);
animationSpeed = a.getFloat(R.styleable.LoadingView_animation_speed, DEFAULT_SPEED);
isNeedAnimation = a.getBoolean(R.styleable.LoadingView_need_animation, true);
a.recycle();
paint.setColor(ballLeftColor);
paint.setStyle(Paint.Style.FILL);
paint.setAntiAlias(true);
paint2.setColor(ballRightColor);
paint2.setStyle(Paint.Style.FILL);
paint2.setAntiAlias(true);
}
private void initMetaballs() {
baseX = this.getMeasuredWidth() / 2;
baseY = this.getMeasuredHeight() / 2;
leftBall = new PointF(baseX, baseY);
rightBall = new PointF(baseX, baseY);
}
@Override
protected void onLayout(boolean changed, int left, int top, int right, int bottom) {
super.onLayout(changed, left, top, right, bottom);
if (changed) {
initMetaballs();
}
}
private float[] getVector(float radians, float length) {
float x = (float) (Math.cos(radians) * length);
float y = (float) (Math.sin(radians) * length);
return new float[]{
x, y
};
}
/**
* @param canvas 画布
* @param v 控制两个圆连接时候长度，间接控制连接线的粗细，该值为1的时候连接线为直线
* @param handle_len_rate
* @param maxDistance
*/
private void metaball(Canvas canvas, float v, float handle_len_rate, float maxDistance) {
float d = getDistance();
float radius1 = radius;
float radius2 = radius;
float pi2 = (float) (Math.PI / 2);
float u1, u2;
if (d > maxDistance) {
canvas.drawCircle(rightBall.x, rightBall.y, radius, paint2);
} else {
canvas.drawCircle(rightBall.x, rightBall.y, radius, paint2);
}
if (radius1 == 0 || radius2 == 0) {
return;
}
if (d > maxDistance || d <= Math.abs(radius1 - radius2)) {
return;
} else if (d < radius1 + radius2) {
u1 = (float) Math.acos((radius1 * radius1 + d * d - radius2 * radius2) /
(2 * radius1 * d));
u2 = (float) Math.acos((radius2 * radius2 + d * d - radius1 * radius1) /
(2 * radius2 * d));
} else {
u1 = 0;
u2 = 0;
}
float[] centermin = new float[]{rightBall.x - leftBall.x, rightBall.y - leftBall.y};
float angle1 = (float) Math.atan2(centermin[1], centermin[0]);
float angle2 = (float) Math.acos((radius1 - radius2) / d);
float angle1a = angle1 + u1 + (angle2 - u1) * v;
float angle1b = angle1 - u1 - (angle2 - u1) * v;
float angle2a = (float) (angle1 + Math.PI - u2 - (Math.PI - u2 - angle2) * v);
float angle2b = (float) (angle1 - Math.PI + u2 + (Math.PI - u2 - angle2) * v);
float[] p1a1 = getVector(angle1a, radius1);
float[] p1b1 = getVector(angle1b, radius1);
float[] p2a1 = getVector(angle2a, radius2);
float[] p2b1 = getVector(angle2b, radius2);
float[] p1a = new float[]{p1a1[0] + leftBall.x, p1a1[1] + leftBall.y};
float[] p1b = new float[]{p1b1[0] + leftBall.x, p1b1[1] + leftBall.y};
float[] p2a = new float[]{p2a1[0] + rightBall.x, p2a1[1] + rightBall.y};
float[] p2b = new float[]{p2b1[0] + rightBall.x, p2b1[1] + rightBall.y};
float[] p1_p2 = new float[]{p1a[0] - p2a[0], p1a[1] - p2a[1]};
float totalRadius = (radius1 + radius2);
float d2 = Math.min(v * handle_len_rate, getLength(p1_p2) / totalRadius);
d2 *= Math.min(1, d * 2 / (radius1 + radius2));
radius1 *= d2;
radius2 *= d2;
float[] sp1 = getVector(angle1a - pi2, radius1);
float[] sp2 = getVector(angle2a + pi2, radius2);
float[] sp3 = getVector(angle2b - pi2, radius2);
float[] sp4 = getVector(angle1b + pi2, radius1);
Path path1 = new Path();
path1.moveTo(p1a[0], p1a[1]);
path1.cubicTo(p1a[0] + sp1[0], p1a[1] + sp1[1], p2a[0] + sp2[0], p2a[1] + sp2[1], p2a[0], p2a[1]);
path1.lineTo(p2b[0], p2b[1]);
path1.cubicTo(p2b[0] + sp3[0], p2b[1] + sp3[1], p1b[0] + sp4[0], p1b[1] + sp4[1], p1b[0], p1b[1]);
path1.lineTo(p1a[0], p1a[1]);
path1.close();
canvas.drawPath(path1, paint2);
}
public float getBallMoveDistance() {
return ballMoveDistance;
}
private float getLength(float[] b) {
return (float) Math.sqrt(b[0] * b[0] + b[1] * b[1]);
}
private float getDistance() {
float x = leftBall.x - rightBall.x;
float y = leftBall.y - rightBall.y;
float d = x * x + y * y;
return (float) Math.sqrt(d);
}
public void setBaseX(float scale) {
if (leftBall == null || rightBall == null) {
return;
}
leftBall.x = baseX - scale * ballMoveDistance / 2;
rightBall.x = baseX + scale * ballMoveDistance / 2;
invalidate();
}
public void setNeedAnimation(boolean animation) {
isNeedAnimation = animation;
invalidate();
}
private void startAnimation() {
if (isNeedAnimation) {
float input = (float) ((System.currentTimeMillis() % 10000 * animationSpeed % 1000) * 1.000 / 1000);
float ratio = (float) ((Math.sin(2 * Math.PI * input)) * ballMoveDistance);
leftBall.x = baseX + ratio;
rightBall.x = baseX - ratio;
float scaleRatio = (float) ((Math.cos(2 * Math.PI * input)) * DEFAULT_RADIUS * 0.2);
radius = (float) (DEFAULT_RADIUS * 0.8 + scaleRatio);
maxTouchDistance = (float) (radius * 2.5);
invalidate();
}
}
@Override
protected void onDraw(Canvas canvas) {
super.onDraw(canvas);
if (leftBall == null || rightBall == null) {
initMetaballs();
}
canvas.drawCircle(leftBall.x, leftBall.y, radius, paint);
metaball(canvas, mv, handleLenRate, maxTouchDistance);
startAnimation();
}
}