自定义View之继承View2

悠悠 2022-06-11 00:07 201阅读 0赞

类似音频播放器的动感条  
![动感音频条][SouthEast]

package com.example.administrator.youku_animi.MyView;
    
    import android.content.Context;
    import android.graphics.Canvas;
    import android.graphics.Color;
    import android.graphics.LinearGradient;
    import android.graphics.Paint;
    import android.graphics.Shader;
    import android.util.AttributeSet;
    import android.view.View;
    
    /** * Created by Administrator on 2017/7/24 0024. */
    
    public class NewView2 extends View { 
        int mRectCount = 20;
        int mWidth = 20 ;
        int offset = 10;
        double mRandom;
        //矩形条的宽度
        int mRectWidth =10;
        int mRectHight = 50;
        Paint mPaint;
        LinearGradient mLinearGradient;
        public NewView2(Context context, AttributeSet attrs)
        {
            super(context, attrs);
            mPaint = new Paint();
            //给画笔设置颜色
            mPaint.setColor(getResources().getColor(android.R.color.holo_blue_bright));
            mPaint.setStyle(Paint.Style.FILL);
            mPaint.setStrokeWidth(4);
        }
    
        @Override
        protected void onDraw(Canvas canvas)
        {
            super.onDraw(canvas);
    
            for (int i = 0; i < mRectCount; i++)
            {
                mRandom = Math.random();
                float currentHight = (float) (mRectHight * mRandom);
                canvas.drawRect(
                        (float) (mWidth * 0.4 / 2 + mRectWidth * i + offset),
                        currentHight,
                        (float) (mWidth * 0.4 / 2 + mRectWidth * (i + 1)),
                        mRectHight,
                        mPaint
                );
            }
    
            postInvalidateDelayed(300);
        }
    
        @Override
        protected void onSizeChanged(int w, int h, int oldw, int oldh)
        {
            super.onSizeChanged(w, h, oldw, oldh);
            mWidth = getWidth();
            mRectHight = getHeight();
            mRectWidth = (int) (mWidth * 0.6 / mRectCount);
            mLinearGradient = new LinearGradient(
                    0,
                    0,
                    mRectWidth,
                    mRectHight,
                    Color.YELLOW,
                    Color.BLUE,
                    Shader.TileMode.CLAMP
            );
            mPaint.setShader(mLinearGradient);
        }
    }

[SouthEast]: /images/20220611/e8c74c3b3eae40a48b40393e57fad467.png