自定义音频条

效果图

代码

public class VoiceView extends View {

    private int mWidth;
    private int mRectHeight;
    private int mRectCount = 10;
    private int mRectWidth;
    private final Paint mPaint;
    private LinearGradient mGradient;
    private int offset = 5;
    private float mCurrentHeight;
    private double mRandom;

    public VoiceView(Context context, AttributeSet attrs) {
        super(context, attrs);
        mPaint = new Paint(Paint.ANTI_ALIAS_FLAG);
        mPaint.setColor(Color.GREEN);
        mPaint.setStyle(Paint.Style.FILL);
    }

    @Override
    protected void onSizeChanged(int w, int h, int oldw, int oldh) {
        super.onSizeChanged(w, h, oldw, oldh);
        mWidth = getWidth();//View的宽度
        mRectHeight = getHeight();//View的高度
        //每个矩形的宽度
        mRectWidth = (int) (mWidth * 0.6 / mRectCount);
        mGradient = new LinearGradient(0,0,mRectWidth,mRectHeight, Color.YELLOW,Color.GREEN, Shader.TileMode.CLAMP);
        //给画笔设置渲染
        mPaint.setShader(mGradient);
    }

    @Override
    protected void onDraw(Canvas canvas) {
        super.onDraw(canvas);
        for (int i = 0; i < mRectCount; i++) {
            mRandom = Math.random();
            mCurrentHeight = (float) (mRectHeight * mRandom);
            canvas.drawRect((int)(mWidth*0.4/2+mRectWidth*i+offset),mCurrentHeight,
                    (int)(mWidth*0.4/2+mRectWidth*(i+1)),mRectHeight,mPaint);
        }
        postInvalidateDelayed(500);//每500毫秒刷新界面
    }
}