1.介绍
首先看下效果图
2.思路
- 初始化一些参数
- 绘制刻度盘
- 绘制刻度盘下的圆弧
- 绘制标题与温度标识
- 绘制旋转按钮
- 绘制温度
- 处理滑动事件
- 提供一些接口方法
3.实现
初始化一些参数
public class TempControlView extends View { private int width; private int height; private int dialRadius; private int arcRadius; private int scaleHeight = dp2px(10); private Paint dialPaint; private Paint arcPaint; private Paint titlePaint; private Paint tempFlagPaint; private Paint buttonPaint; private Paint tempPaint; private String title = "最高温度设置"; private int temperature; private int minTemp = 15; private int maxTemp = 30; private int angleRate = 4; private Bitmap buttonImage = BitmapFactory.decodeResource(getResources(), R.mipmap.btn_rotate); private Bitmap buttonImageShadow = BitmapFactory.decodeResource(getResources(), R.mipmap.btn_rotate_shadow); private PaintFlagsDrawFilter paintFlagsDrawFilter; private OnTempChangeListener onTempChangeListener; private float rotateAngle; private float currentAngle; ... @Override protected void onSizeChanged(int w, int h, int oldw, int oldh) { super.onSizeChanged(w, h, oldw, oldh); width = height = Math.min(h, w); dialRadius = width / 2 - dp2px(20); arcRadius = dialRadius - dp2px(20); } ...}
- 1
- 2
- 3
- 4
- 5
- 6
- 7
- 8
- 9
- 10
- 11
- 12
- 13
- 14
- 15
- 16
- 17
- 18
- 19
- 20
- 21
- 22
- 23
- 24
- 25
- 26
- 27
- 28
- 29
- 30
- 31
- 32
- 33
- 34
- 35
- 36
- 37
- 38
- 39
- 40
- 41
- 42
- 43
- 44
- 45
- 46
- 47
- 48
- 49
- 50
- 51
- 52
- 53
- 54
- 55
- 56
- 57
- 58
- 59
- 60
- 61
- 62
- 63
- 64
- 65
- 66
- 67
- 1
- 2
- 3
- 4
- 5
- 6
- 7
- 8
- 9
- 10
- 11
- 12
- 13
- 14
- 15
- 16
- 17
- 18
- 19
- 20
- 21
- 22
- 23
- 24
- 25
- 26
- 27
- 28
- 29
- 30
- 31
- 32
- 33
- 34
- 35
- 36
- 37
- 38
- 39
- 40
- 41
- 42
- 43
- 44
- 45
- 46
- 47
- 48
- 49
- 50
- 51
- 52
- 53
- 54
- 55
- 56
- 57
- 58
- 59
- 60
- 61
- 62
- 63
- 64
- 65
- 66
- 67
绘制刻度盘
以屏幕中心为画布原点,圆弧角度为270°,绘制未选中与选中状态的刻度盘。
旋转方法中多减的2°是后期调整所得,不用在意。
/** * 绘制刻度盘 * * @param canvas 画布 */private void drawScale(Canvas canvas) { canvas.save(); canvas.translate(getWidth() / 2, getHeight() / 2); canvas.rotate(-133); dialPaint.setColor(Color.parseColor("#3CB7EA")); for (int i = 0; i < 60; i++) { canvas.drawLine(0, -dialRadius, 0, -dialRadius + scaleHeight, dialPaint); canvas.rotate(4.5f); } canvas.rotate(90); dialPaint.setColor(Color.parseColor("#E37364")); for (int i = 0; i < (temperature - minTemp) * angleRate; i++) { canvas.drawLine(0, -dialRadius, 0, -dialRadius + scaleHeight, dialPaint); canvas.rotate(4.5f); } canvas.restore();}
- 1
- 2
- 3
- 4
- 5
- 6
- 7
- 8
- 9
- 10
- 11
- 12
- 13
- 14
- 15
- 16
- 17
- 18
- 19
- 20
- 21
- 22
- 23
- 24
- 1
- 2
- 3
- 4
- 5
- 6
- 7
- 8
- 9
- 10
- 11
- 12
- 13
- 14
- 15
- 16
- 17
- 18
- 19
- 20
- 21
- 22
- 23
- 24
绘制刻度盘下的圆弧
/** * 绘制刻度盘下的圆弧 * * @param canvas 画布 */private void drawArc(Canvas canvas) { canvas.save(); canvas.translate(getWidth() / 2, getHeight() / 2); canvas.rotate(135 + 2); RectF rectF = new RectF(-arcRadius, -arcRadius, arcRadius, arcRadius); canvas.drawArc(rectF, 0, 265, false, arcPaint); canvas.restore();}
绘制标题与温度标识
/** * 绘制标题与温度标识 * * @param canvas 画布 */ private void drawText(Canvas canvas) { canvas.save(); float titleWidth = titlePaint.measureText(title); canvas.drawText(title, (width - titleWidth) / 2, dialRadius * 2 + dp2px(15), titlePaint); String minTempFlag = minTemp < 10 ? "0" + minTemp : minTemp + ""; float tempFlagWidth = titlePaint.measureText(maxTemp + ""); canvas.rotate(55, width / 2, height / 2); canvas.drawText(minTempFlag, (width - tempFlagWidth) / 2, height + dp2px(5), tempFlagPaint); canvas.rotate(-105, width / 2, height / 2); canvas.drawText(maxTemp + "", (width - tempFlagWidth) / 2, height + dp2px(5), tempFlagPaint); canvas.restore(); }
- 1
- 2
- 3
- 4
- 5
- 6
- 7
- 8
- 9
- 10
- 11
- 12
- 13
- 14
- 15
- 16
- 17
- 18
- 19
- 20
- 21
- 22
- 23
- 24
- 1
- 2
- 3
- 4
- 5
- 6
- 7
- 8
- 9
- 10
- 11
- 12
- 13
- 14
- 15
- 16
- 17
- 18
- 19
- 20
- 21
- 22
- 23
- 24
绘制旋转按钮
/** * 绘制旋转按钮 * * @param canvas 画布 */private void drawButton(Canvas canvas) { int buttonWidth = buttonImage.getWidth(); int buttonHeight = buttonImage.getHeight(); int buttonShadowWidth = buttonImageShadow.getWidth(); int buttonShadowHeight = buttonImageShadow.getHeight(); canvas.drawBitmap(buttonImageShadow, (width - buttonShadowWidth) / 2, (height - buttonShadowHeight) / 2, buttonPaint); Matrix matrix = new Matrix(); matrix.setTranslate(buttonWidth / 2, buttonHeight / 2); matrix.preRotate(45 + rotateAngle); matrix.preTranslate(-buttonWidth / 2, -buttonHeight / 2); matrix.postTranslate((width - buttonWidth) / 2, (height - buttonHeight) / 2); canvas.setDrawFilter(paintFlagsDrawFilter); canvas.drawBitmap(buttonImage, matrix, buttonPaint);}
- 1
- 2
- 3
- 4
- 5
- 6
- 7
- 8
- 9
- 10
- 11
- 12
- 13
- 14
- 15
- 16
- 17
- 18
- 19
- 20
- 21
- 22
- 23
- 24
- 25
- 26
- 27
- 28
- 29
- 30
- 31
- 1
- 2
- 3
- 4
- 5
- 6
- 7
- 8
- 9
- 10
- 11
- 12
- 13
- 14
- 15
- 16
- 17
- 18
- 19
- 20
- 21
- 22
- 23
- 24
- 25
- 26
- 27
- 28
- 29
- 30
- 31
绘制温度
/** * 绘制温度 * * @param canvas 画布 */private void drawTemp(Canvas canvas) { canvas.save(); canvas.translate(getWidth() / 2, getHeight() / 2); float tempWidth = tempPaint.measureText(temperature + ""); float tempHeight = (tempPaint.ascent() + tempPaint.descent()) / 2; canvas.drawText(temperature + "°", -tempWidth / 2 - dp2px(5), -tempHeight, tempPaint); canvas.restore();}
处理滑动事件
private boolean isDown;private boolean isMove;@Overridepublic boolean onTouchEvent(MotionEvent event) { switch (event.getAction()) { case MotionEvent.ACTION_DOWN: isDown = true; float downX = event.getX(); float downY = event.getY(); currentAngle = calcAngle(downX, downY); break; case MotionEvent.ACTION_MOVE: isMove = true; float targetX; float targetY; downX = targetX = event.getX(); downY = targetY = event.getY(); float angle = calcAngle(targetX, targetY); float angleIncreased = angle - currentAngle; if (angleIncreased < -270) { angleIncreased = angleIncreased + 360; } else if (angleIncreased > 270) { angleIncreased = angleIncreased - 360; } IncreaseAngle(angleIncreased); currentAngle = angle; invalidate(); break; case MotionEvent.ACTION_CANCEL: case MotionEvent.ACTION_UP: { if (isDown && isMove) { rotateAngle = (float) ((temperature - minTemp) * angleRate * 4.5); invalidate(); onTempChangeListener.change(temperature); isDown = false; isMove = false; } break; } } return true;}/** * 以按钮圆心为坐标圆点,建立坐标系,求出(targetX, targetY)坐标与x轴的夹角 * * @param targetX x坐标 * @param targetY y坐标 * @return (targetX, targetY)坐标与x轴的夹角 */private float calcAngle(float targetX, float targetY) { float x = targetX - width / 2; float y = targetY - height / 2; double radian; if (x != 0) { float tan = Math.abs(y / x); if (x > 0) { if (y >= 0) { radian = Math.atan(tan); } else { radian = 2 * Math.PI - Math.atan(tan); } } else { if (y >= 0) { radian = Math.PI - Math.atan(tan); } else { radian = Math.PI + Math.atan(tan); } } } else { if (y > 0) { radian = Math.PI / 2; } else { radian = -Math.PI / 2; } } return (float) ((radian * 180) / Math.PI);}/** * 增加旋转角度 * * @param angle 增加的角度 */private void IncreaseAngle(float angle) { rotateAngle += angle; if (rotateAngle < 0) { rotateAngle = 0; } else if (rotateAngle > 270) { rotateAngle = 270; } temperature = (int) (rotateAngle / 4.5) / angleRate + minTemp;}
- 1
- 2
- 3
- 4
- 5
- 6
- 7
- 8
- 9
- 10
- 11
- 12
- 13
- 14
- 15
- 16
- 17
- 18
- 19
- 20
- 21
- 22
- 23
- 24
- 25
- 26
- 27
- 28
- 29
- 30
- 31
- 32
- 33
- 34
- 35
- 36
- 37
- 38
- 39
- 40
- 41
- 42
- 43
- 44
- 45
- 46
- 47
- 48
- 49
- 50
- 51
- 52
- 53
- 54
- 55
- 56
- 57
- 58
- 59
- 60
- 61
- 62
- 63
- 64
- 65
- 66
- 67
- 68
- 69
- 70
- 71
- 72
- 73
- 74
- 75
- 76
- 77
- 78
- 79
- 80
- 81
- 82
- 83
- 84
- 85
- 86
- 87
- 88
- 89
- 90
- 91
- 92
- 93
- 94
- 95
- 96
- 97
- 98
- 99
- 100
- 101
- 102
- 103
- 104
- 1
- 2
- 3
- 4
- 5
- 6
- 7
- 8
- 9
- 10
- 11
- 12
- 13
- 14
- 15
- 16
- 17
- 18
- 19
- 20
- 21
- 22
- 23
- 24
- 25
- 26
- 27
- 28
- 29
- 30
- 31
- 32
- 33
- 34
- 35
- 36
- 37
- 38
- 39
- 40
- 41
- 42
- 43
- 44
- 45
- 46
- 47
- 48
- 49
- 50
- 51
- 52
- 53
- 54
- 55
- 56
- 57
- 58
- 59
- 60
- 61
- 62
- 63
- 64
- 65
- 66
- 67
- 68
- 69
- 70
- 71
- 72
- 73
- 74
- 75
- 76
- 77
- 78
- 79
- 80
- 81
- 82
- 83
- 84
- 85
- 86
- 87
- 88
- 89
- 90
- 91
- 92
- 93
- 94
- 95
- 96
- 97
- 98
- 99
- 100
- 101
- 102
- 103
- 104
提供一些接口方法
/** * 设置温度 * * @param minTemp 最小温度 * @param maxTemp 最大温度 * @param temp 设置的温度 */public void setTemp(int minTemp, int maxTemp, int temp) { this.minTemp = minTemp; this.maxTemp = maxTemp; this.temperature = temp; this.angleRate = 60 / (maxTemp - minTemp); rotateAngle = (float) ((temp - minTemp) * angleRate * 4.5); invalidate();}/** * 设置温度改变监听 * * @param onTempChangeListener 监听接口 */public void setOnTempChangeListener(OnTempChangeListener onTempChangeListener) { this.onTempChangeListener = onTempChangeListener;}/** * 温度改变监听接口 */public interface OnTempChangeListener { /** * 回调方法 * * @param temp 温度 */ void change(int temp);}
- 1
- 2
- 3
- 4
- 5
- 6
- 7
- 8
- 9
- 10
- 11
- 12
- 13
- 14
- 15
- 16
- 17
- 18
- 19
- 20
- 21
- 22
- 23
- 24
- 25
- 26
- 27
- 28
- 29
- 30
- 31
- 32
- 33
- 34
- 35
- 36
- 1
- 2
- 3
- 4
- 5
- 6
- 7
- 8
- 9
- 10
- 11
- 12
- 13
- 14
- 15
- 16
- 17
- 18
- 19
- 20
- 21
- 22
- 23
- 24
- 25
- 26
- 27
- 28
- 29
- 30
- 31
- 32
- 33
- 34
- 35
- 36
4.写在最后
源码已托管到GitHub上,欢迎Fork,觉得还不错就Start一下吧!
点击下载源码
GitHub地址:https://github.com/alidili/TempControlView
欢迎同学们吐槽评论,如果你觉得本篇博客对你有用,那么就留个言或者顶一下吧(^-^)