本文比较详细的介绍了绘制圆环及圆弧的基础知识,为实现钉钉运动步数打下基础,实现了下面的效果,实现钉钉运动就灰常简单了,本文实现的初步效果如下:
如果想直接看钉钉运动的最终效果,请戳:Android进阶之自定义控件(2)高仿钉钉运动步数实现可动的进度圆环(下)
1、圆环的绘制
2、绘制背景圆环和进度圆环
3、绘制中间的文字
(1)使用drawArc(RectF oval, float startAngle, float sweepAngle, boolean useCenter, Paint paint)绘制圆环:
public class SportStepView extends View {
private Paint mPaint;
//圆环绘制的宽度
private int mRoundWidth = 40;
public SportStepView(Context context) {
this(context, null);
}
public SportStepView(Context context, @Nullable AttributeSet attrs) {
this(context, attrs, 0);
}
public SportStepView(Context context, @Nullable AttributeSet attrs, int defStyleAttr) {
super(context, attrs, defStyleAttr);
init();
}
@Override
protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
super.onMeasure(widthMeasureSpec, heightMeasureSpec);
//获取宽的模式
int widthMode = MeasureSpec.getMode(widthMeasureSpec);
int heightMode = MeasureSpec.getMode(heightMeasureSpec);
//获取宽的尺寸
int widthSize = MeasureSpec.getSize(widthMeasureSpec);
int heightSize = MeasureSpec.getSize(heightMeasureSpec);
//对wrap_content这种模式进行处理
if (heightMode == MeasureSpec.AT_MOST) {
heightSize = widthSize;
}
//绘制圆环以宽度为标准,保存丈量结果
setMeasuredDimension(widthSize, heightSize);
}
private void init() {
mPaint = new Paint();
mPaint.setAntiAlias(true);
mPaint.setStyle(Paint.Style.STROKE);
mPaint.setColor(Color.RED);
mPaint.setStrokeWidth(mRoundWidth);
}
@Override
protected void onDraw(Canvas canvas) {
super.onDraw(canvas);
//绘制圆,设置画笔的Style为Paint.Style.STROKE,则绘制出来的为圆环,否则绘制出来的为圆
//canvas.drawCircle(getWidth() / 2, getHeight() / 2, getWidth() / 2 - mRoundWidth / 2, mPaint);
RectF oval = new RectF(0 , 0, getWidth(), getWidth());
//画圆弧 useCenter:是否显示圆内的横线 下面的绘制0,360的圆弧,也可以实现绘制圆环的效果
canvas.drawArc(oval, 0, 360, false, mPaint);
}
}
会发现显示不全,绘制超出边界了,因为圆的宽度是在当前半径向两边展开的。如下图分析得知,圆所在的矩形区域不是rect(为屏幕的矩形区域),而是real Rect所在的区域:
因此只需要修改如下即可。
RectF oval = new RectF(0 + mRoundWidth / 2, 0 + mRoundWidth / 2, getWidth() - mRoundWidth / 2, getWidth() - mRoundWidth / 2);
// RectF oval = new RectF(0 , 0, getWidth(), getWidth());
//画圆弧 useCenter:是否显示圆内的横线 下面的绘制0,360的圆弧,也可以实现绘制圆环的效果
canvas.drawArc(oval, 0, 360, false, mPaint);
修改后达到我们的预期效果:
(2)如果只是绘制上面的圆环效果,还可以使用: canvas.drawCircle()的方式实现,这种方法更简单:
//绘制圆,设置画笔的Style为Paint.Style.STROKE,则绘制出来的为圆环,否则绘制出来的为圆
//由于圆环本身有宽度,所以半径要减去圆环宽度的一半,不然一部分圆会在view外面。
canvas.drawCircle(getWidth() / 2, getHeight() / 2, getWidth() / 2 - mRoundWidth / 2, mPaint);
(3)接下来我们来实现背景圆环+进度圆环的效果了,利用drawCircle绘制背景圆环,drawArc()绘制进度圆环,预期效果如下:
这个很简单,再画个圆弧即可:
@Override
protected void onDraw(Canvas canvas) {
super.onDraw(canvas);
//绘制背景圆环,设置画笔的Style为Paint.Style.STROKE,则绘制出来的为圆环,否则绘制出来的为圆
//正常情况下
canvas.drawCircle(getWidth() / 2, getHeight() / 2, getWidth() / 2 - mRoundWidth / 2, mPaint);
//正常情况下,绘制进度圆环
RectF oval = new RectF(0 + mProgressRoundWidth / 2, 0 + mProgressRoundWidth / 2, getWidth() - mProgressRoundWidth / 2, getWidth() - mProgressRoundWidth / 2);
//画圆弧 useCenter:是否显示圆内的横线 下面的绘制0,360的圆弧,也可以实现绘制圆环的效果
canvas.drawArc(oval, 0, 300, false, mProgressPaint);
}
但是光这样处理,会有个小问题,就是当背景圆环和进度圆环宽度不一致时,会出现下面的问题。
解决方法:以宽度较大为准即可。
@Override
protected void onDraw(Canvas canvas) {
super.onDraw(canvas);
/**
* 如果背景圆环和进度圆环宽度不一致,都以较大的宽度为准绘制。避免出现两者显示不居中的问题
*/
//绘制背景圆环,设置画笔的Style为Paint.Style.STROKE,则绘制出来的为圆环,否则绘制出来的为圆
// canvas.drawCircle(getWidth() / 2, getHeight() / 2, getWidth() / 2, mPaint);
if (mRoundWidth < mProgressRoundWidth) {
canvas.drawCircle(getWidth() / 2, getHeight() / 2, getWidth() / 2 - mProgressRoundWidth / 2, mPaint);
} else {
//正常情况下
canvas.drawCircle(getWidth() / 2, getHeight() / 2, getWidth() / 2 - mRoundWidth / 2, mPaint);
}
if (mRoundWidth < mProgressRoundWidth) {
// //正常情况下,绘制进度圆环
RectF oval = new RectF(0 + mProgressRoundWidth / 2, 0 + mProgressRoundWidth / 2, getWidth() - mProgressRoundWidth / 2, getWidth() - mProgressRoundWidth / 2);
// RectF oval = new RectF(0 , 0, getWidth(), getWidth());
//画圆弧 useCenter:是否显示圆内的横线 下面的绘制0,360的圆弧,也可以实现绘制圆环的效果
canvas.drawArc(oval, 0, 300, false, mProgressPaint);
} else {
//绘制进度圆环
RectF oval = new RectF(0 + mRoundWidth / 2, 0 + mRoundWidth / 2, getWidth() - mRoundWidth / 2, getWidth() - mRoundWidth / 2);
//画圆弧 useCenter:是否显示圆内的横线 下面的绘制0,360的圆弧,也可以实现绘制圆环的效果
canvas.drawArc(oval, 0, 300, false, mProgressPaint);
}
}
(4)绘制居中的进度文字
代码实现:
//绘制中间的文字
Rect textRect = new Rect();
//进度百分比
int progressPercent = (int) (mCurrentProgress * 1f / mMaxProgress * 100);
String mShowText = progressPercent + "%";
mTextPaint.getTextBounds(mShowText, 0, mShowText.length(), textRect);
canvas.drawText(mShowText, getWidth() / 2 - textRect.width() / 2, getHeight() / 2 + textRect.height() / 2, mTextPaint);
(5)处理圆环进度和文字进度的动态显示
方法一:开一个分线程,动态改变进度的值,不断绘制达到进度变化的效果。
方法二:下篇会介绍到_
在测试的Activity中使用:
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
// mytextview = findViewById(R.id.mytextview);
final SportStepView sportStepView = findViewById(R.id.sportstepview);
mCurrentProgress = 80;
//速度,值越大,变化速度越快
rate = 1;
//开一个分线程,动态改变进度的值,不断绘制达到进度变化的效果
new Thread(new Runnable() {
@Override
public void run() {
sportStepView.setCurrentProgress(0);
for (int i = 0; i < mCurrentProgress / rate; i++) {
sportStepView.setCurrentProgress(sportStepView.getCurrentProgress() + rate);
SystemClock.sleep(20);
// pb_progress.invalidate();//invalidate()必须在主线程中执行,此处不能使用
sportStepView.postInvalidate();//强制重绘,postInvalidate()可以在主线程也可以在分线程中执行
}
}
}).start();
}
完整代码:
package com.example.jojo.learn.customview;
import android.content.Context;
import android.content.res.TypedArray;
import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.Paint;
import android.graphics.Rect;
import android.graphics.RectF;
import android.support.annotation.Nullable;
import android.util.AttributeSet;
import android.util.TypedValue;
import android.view.View;
import com.example.jojo.learn.R;
/**
* Created by JoJo on 2018/7/31.
* wechat:18510829974
* description: 仿钉钉运动步数
*/
public class SportStepView extends View {
//绘制背景圆环的画笔
private Paint mPaint;
//绘制外面进度的圆环的画笔
private Paint mProgressPaint;
//绘制外面进度的圆环的画笔
private Paint mTextPaint;
//背景圆弧的绘制的宽度
private int mRoundWidth = 40;
//进度圆环的宽度
private float mProgressRoundWidth = 60;
private int mTextSize = 40;//单位 sp
//圆环最大进度
private int mMaxProgress = 100;
//圆环当前进度
private int mCurrentProgress = 0;
public SportStepView(Context context) {
this(context, null);
}
public SportStepView(Context context, @Nullable AttributeSet attrs) {
this(context, attrs, 0);
}
public SportStepView(Context context, @Nullable AttributeSet attrs, int defStyleAttr) {
super(context, attrs, defStyleAttr);
init();
}
@Override
protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
super.onMeasure(widthMeasureSpec, heightMeasureSpec);
//获取宽的模式
int widthMode = MeasureSpec.getMode(widthMeasureSpec);
int heightMode = MeasureSpec.getMode(heightMeasureSpec);
//获取宽的尺寸
int widthSize = MeasureSpec.getSize(widthMeasureSpec);
int heightSize = MeasureSpec.getSize(heightMeasureSpec);
//对wrap_content这种模式进行处理
if (heightMode == MeasureSpec.AT_MOST) {
heightSize = widthSize;
}
//以宽度为标准保存丈量结果
setMeasuredDimension(widthSize, heightSize);
}
private void init() {
mPaint = new Paint();
mPaint.setAntiAlias(true);
mPaint.setStyle(Paint.Style.STROKE);
mPaint.setColor(Color.RED);
mPaint.setStrokeWidth(mRoundWidth);
mProgressPaint = new Paint();
mProgressPaint.setAntiAlias(true);// 抗锯齿效果
mProgressPaint.setStyle(Paint.Style.STROKE);
mProgressPaint.setColor(Color.YELLOW);
mProgressPaint.setStrokeCap(Paint.Cap.ROUND);// 圆形笔头
mProgressPaint.setStrokeWidth(mProgressRoundWidth);
mTextPaint = new Paint();
mTextPaint.setAntiAlias(true);// 抗锯齿效果
mTextPaint.setStyle(Paint.Style.STROKE);
mTextPaint.setColor(Color.BLACK);
mTextPaint.setTextSize(sp2px(mTextSize));
}
@Override
protected void onDraw(Canvas canvas) {
super.onDraw(canvas);
/**
* 如果背景圆环和进度圆环宽度不一致,都以较大的宽度为准绘制。避免出现两者显示不居中的问题
*/
//绘制背景圆环,设置画笔的Style为Paint.Style.STROKE,则绘制出来的为圆环,否则绘制出来的为圆
// canvas.drawCircle(getWidth() / 2, getHeight() / 2, getWidth() / 2, mPaint);
if (mRoundWidth < mProgressRoundWidth) {
canvas.drawCircle(getWidth() / 2, getHeight() / 2, getWidth() / 2 - mProgressRoundWidth / 2, mPaint);
} else {
//正常情况下
canvas.drawCircle(getWidth() / 2, getHeight() / 2, getWidth() / 2 - mRoundWidth / 2, mPaint);
}
if (mRoundWidth < mProgressRoundWidth) {
// //正常情况下,绘制进度圆环
RectF oval = new RectF(0 + mProgressRoundWidth / 2, 0 + mProgressRoundWidth / 2, getWidth() - mProgressRoundWidth / 2, getWidth() - mProgressRoundWidth / 2);
// RectF oval = new RectF(0 , 0, getWidth(), getWidth());
//画圆弧 useCenter:是否显示圆内的横线 下面的绘制0,360的圆弧,也可以实现绘制圆环的效果
canvas.drawArc(oval, 0 + 90, mCurrentProgress * 1f / mMaxProgress * 360, false, mProgressPaint);
} else {
//绘制进度圆环
RectF oval = new RectF(0 + mRoundWidth / 2, 0 + mRoundWidth / 2, getWidth() - mRoundWidth / 2, getWidth() - mRoundWidth / 2);
//画圆弧 useCenter:是否显示圆内的横线 下面的绘制0,360的圆弧,也可以实现绘制圆环的效果
canvas.drawArc(oval, 0 + 90, mCurrentProgress * 1f / mMaxProgress * 360, false, mProgressPaint);
}
//绘制中间的文字
Rect textRect = new Rect();
//进度百分比
int progressPercent = (int) (mCurrentProgress * 1f / mMaxProgress * 100);
String mShowText = progressPercent + "%";
mTextPaint.getTextBounds(mShowText, 0, mShowText.length(), textRect);
canvas.drawText(mShowText, getWidth() / 2 - textRect.width() / 2, getHeight() / 2 + textRect.height() / 2, mTextPaint);
}
public void setCurrentProgress(int currentProgress) {
this.mCurrentProgress = currentProgress;
}
public void setMaxProgress(int maxProgress) {
this.mMaxProgress = maxProgress;
}
public int getMaxProgress() {
return mMaxProgress;
}
public int getCurrentProgress() {
return mCurrentProgress;
}
/**
* 将sp转换成px
*
* @param sp
* @return
*/
private int sp2px(int sp) {
return (int) TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_SP, sp,
getResources().getDisplayMetrics());
}
}
涉及到的自定义属性
<!--SportStepView-->
<declare-styleable name="SportStepView">
<!--圆环半径-->
<attr name="radius" format="dimension"></attr>
<attr name="outerRoundColor" format="color"></attr>
<attr name="innerRoundColor" format="color"></attr>
</declare-styleable>
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Kotlin+组件化开发实践—开源项目Designer-App
Designer项目算是倾注了我蛮多心血了,每个页面和功能都当成是上线的App来做,App的logo还特地做了UI设计😃力求做到精致和完善,其中还包括了很多自己项目开发中的经验汇总和对新技术的探索和整合,希望对各位读者有所帮助,欢迎点个star,follow,或者给个小心心,嘻嘻😝也可以分享给你更多的朋友一起学习,您的支持是我不断前进的动力。如果有任何问题,欢迎在GitHub上给我提issue或者留言。