继承自View的自定义控件的warp_content和padding属性处理

继承自view的自定义控件的wrap_content和padding两个属性不会生效，解决方法

/**
 * 自定义一个圆形
 * @author luoshen
 * 2016年11月29日下午1:28:04
 */
public class CircleView extends View{

	
	private int mColor = Color.RED;
	
	private Paint mPaint  = new Paint(Paint.ANTI_ALIAS_FLAG);
	
	public CircleView(Context context, AttributeSet attrs, int defStyleAttr) {
		super(context, attrs, defStyleAttr);
		
		init();
	}

	public CircleView(Context context, AttributeSet attrs) {
		super(context, attrs);
		init();
	}

	public CircleView(Context context) {
		super(context);
		init();
	}
	
	
	private void init(){
		
		mPaint.setColor(mColor);
	}
	
	/**
	 * 此方法中的代码是为了让wrap_content属性生效，并给此属性设置宽高
	 */
	@Override
	protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
		super.onMeasure(widthMeasureSpec, heightMeasureSpec);
		//取出宽度的测量模式
		int widthSpecMode = MeasureSpec.getMode(widthMeasureSpec);
		//取出宽度的确切数值
		int widthSpecSize = MeasureSpec.getSize(widthMeasureSpec);
		//取出高度的测量模式
		int heightSpecMode = MeasureSpec.getMode(heightMeasureSpec);
		//取出高度的确切数值
		int heightSpecSize = MeasureSpec.getSize(heightMeasureSpec);
		
		if (widthSpecMode == MeasureSpec.AT_MOST && heightMeasureSpec == MeasureSpec.AT_MOST) {
			//设置wrap_content属性的宽高
			setMeasuredDimension(200, 200);
			
		}else if (widthSpecMode == MeasureSpec.AT_MOST) {
			
			setMeasuredDimension(200, heightSpecSize);
			
		}else if (heightSpecMode == MeasureSpec.AT_MOST) {
			
			setMeasuredDimension(widthSpecSize, 200);
			
		}
	}
	
	
	/**
	 * 此方法内部的代码是为了让padding属性生效
	 * 
	 * 并且画了一个圆
	 */
	@Override
	protected void onDraw(Canvas canvas) {
		super.onDraw(canvas);
		
		int paddingLeft = getPaddingLeft();
		
		int paddingRight = getPaddingRight();
		
		int paddingTop = getPaddingTop();
		
		int paddingBottom = getPaddingBottom();
		//减去padding值
		int width = getWidth() - paddingLeft - paddingRight;
		int height = getHeight() - paddingBottom - paddingTop;
		
		int radius = Math.min(width,height)/2;
		
		canvas.drawCircle(paddingLeft+width/2, paddingTop+height/2, radius, mPaint);
	}
	

}