本文共 4989 字，大约阅读时间需要 16 分钟。

view代码：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.os.Build;import android.support.annotation.Nullable;import android.support.annotation.RequiresApi;import android.text.TextUtils;import android.util.AttributeSet;import android.util.Log;import android.view.View;import com.xlkx.findreagent.R;import com.xlkx.findreagent.utils.SizeUtil;public class CircleNumberView extends View {    //画笔    Paint paint;    String number = "99";    int padding = 10;    float textSize = 15.0f;    //view的直径    float radius;    //设置现实的数字    public void setNumber(String number) {        this.number = number;    }    private void initView() {        if (paint == null) {            paint = new Paint();            paint.setTextSize(SizeUtil.sp2px(getContext(), textSize));            //如果需要透明度，透明度应该加在前两位            paint.setColor(Color.parseColor("#ff0000"));            paint.setAntiAlias(true);            paint.setFilterBitmap(true);//位图过滤            ;        }        //文字所占的区域，用来确定文字的起始坐标        Rect rect = null;        if (rect == null) {            rect = new Rect();        }        paint.getTextBounds("99+", 0, "99+".length(), rect);        float viewWidth = rect.width();        float viewHeight = rect.height();        if (viewWidth >= viewHeight) {            radius = viewWidth + padding * 2;            ;        } else {            radius = viewHeight + padding * 2;            ;        }        Log.e("开始测量时候的radius", radius + "");    }    private void initAtters(Context context, @Nullable AttributeSet attrs) {        TypedArray array = context.obtainStyledAttributes(attrs, R.styleable.CircleNumberView);        textSize = array.getFloat(R.styleable.CircleNumberView_textSize, 12.0f);        padding = array.getInt(R.styleable.CircleNumberView_textPadding, 10);        number = array.getString(R.styleable.CircleNumberView_textNumber);        if (TextUtils.isEmpty(number)) {            number = "111";        } else {        }    }    @Override    protected void onDraw(Canvas canvas) {        Log.e("onDraw时候的radius", radius + "");        canvas.drawCircle(radius / 2.0f, radius / 2.0f, radius / 2.0f, paint);        Paint paint1 = new Paint();        paint1.setTextSize(SizeUtil.sp2px(getContext(), textSize));        paint1.setColor(Color.parseColor("#ffffff"));        paint1.setAntiAlias(true);        paint1.setFilterBitmap(true);//位图过滤        ;        //设置文字显示时候的居中方式，不设置的话相当于Paint.Align.LEFT，则需要自己计算起点位置，需要自行处理精度问题        //设置的坐标为文字的中线        paint1.setTextAlign(Paint.Align.CENTER);        //设置的坐标为文字的左侧边线        //paint1.setTextAlign(Paint.Align.LEFT);        //设置的坐标为文字的右侧边线        //paint1.setTextAlign(Paint.Align.RIGHT);        //文字所占的区域，用来确定文字的起始坐标        Rect rect1 = null;        if (rect1 == null) {            rect1 = new Rect();        }        //39-15.5=23.5        if (Integer.parseInt(number) > 99) {            paint1.getTextBounds("99+", 0, "99+".length(), rect1);        } else {            paint1.getTextBounds(number, 0, number.length(), rect1);        }        //为了让文字纵向居中，计算正确的Y值        Paint.FontMetrics fontMetrics = paint1.getFontMetrics();        //ascent的绝对值=descent+2*(文字纵向中线与基准线的高度差)        //float baseline = 0;        //Math.abs(fontMetrics.ascent) =fontMetrics.descent+2*(baseline-height/2);        float y = radius / 2.0f + (Math.abs(fontMetrics.ascent) - fontMetrics.descent) / 2.0f;        Log.e("实际文字的宽度是", rect1.width() + "");        float startX = radius / 2.0f - rect1.width() / 2.0f;        startX = radius / 2.0f;        Log.e("实际文字的startX是", startX + "");        if (Integer.parseInt(number) > 99) {            canvas.drawText("99+", startX + getPaddingLeft(), y + getPaddingTop(), paint1);        } else {            canvas.drawText(number, startX + getPaddingLeft(), y + getPaddingTop(), paint1);        }        Log.e("最后绘制的文字是", number);    }    @Override    protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {        //    super.onMeasure(widthMeasureSpec, heightMeasureSpec);        setMeasuredDimension((int) radius, (int) radius);    }    public CircleNumberView(Context context) {        super(context);        initView();    }    public CircleNumberView(Context context, @Nullable AttributeSet attrs) {        super(context, attrs);        initAtters(context, attrs);        initView();    }    public CircleNumberView(Context context, @Nullable AttributeSet attrs, int defStyleAttr) {        super(context, attrs, defStyleAttr);        initAtters(context, attrs);        initView();    }    @RequiresApi(api = Build.VERSION_CODES.LOLLIPOP)    public CircleNumberView(Context context, @Nullable AttributeSet attrs, int defStyleAttr, int defStyleRes) {        super(context, attrs, defStyleAttr, defStyleRes);        initAtters(context, attrs);        initView();    }}atters代码
   
       
            
             
             
         
    
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