Android自定义RadioButton以控制drawableTop等方向的图片大小

通常在一般的APP中，都会在主页的下方设置3到5个按钮进行主界面的切换，而这种切换实现的方式有很多，比如RadioButton，TabHost，自定义等，本篇主讲RadioButton的实现方式。

优势：简单粗暴，易于实现，易于控制。

劣势：扩展性不强。比如中间的图标放大，在购物车的图标上实现小红点数量提示等，但也总有解决的方案，小红点数量提示可参考http://blog.csdn.net/yechaoa/article/details/53236418。

直入正题，效果图：

1.新建MyRadioButton类，继承RadioButton

package com.example.yechaoa.radiobuttondemo;

import android.content.Context;
import android.content.res.TypedArray;
import android.graphics.drawable.Drawable;
import android.util.AttributeSet;
import android.widget.RadioButton;

/**
 * Created by yechao on 2016/12/1.
 * Describe：可控制drawableTop等图片的大小
 */

public class MyRadioButton extends RadioButton {

    private int mDrawableSize;// xml文件中设置的大小

    public MyRadioButton(Context context) {
        this(context, null, 0);
    }

    public MyRadioButton(Context context, AttributeSet attrs) {
        this(context, attrs, 0);
    }

    public MyRadioButton(Context context, AttributeSet attrs, int defStyle) {
        super(context, attrs, defStyle);
        Drawable drawableLeft = null, drawableTop = null, drawableRight = null, drawableBottom = null;
        TypedArray a = context.obtainStyledAttributes(attrs, R.styleable.MyRadioButton);

        int n = a.getIndexCount();
        for (int i = 0; i < n; i++) {
            int attr = a.getIndex(i);
            switch (attr) {
                case R.styleable.MyRadioButton_drawableSize:
                    mDrawableSize = a.getDimensionPixelSize(R.styleable.MyRadioButton_drawableSize, 50);
                    break;
                case R.styleable.MyRadioButton_drawableTop:
                    drawableTop = a.getDrawable(attr);
                    break;
                case R.styleable.MyRadioButton_drawableBottom:
                    drawableRight = a.getDrawable(attr);
                    break;
                case R.styleable.MyRadioButton_drawableRight:
                    drawableBottom = a.getDrawable(attr);
                    break;
                case R.styleable.MyRadioButton_drawableLeft:
                    drawableLeft = a.getDrawable(attr);
                    break;
                default:
                    break;
            }
        }
        a.recycle();

        setCompoundDrawablesWithIntrinsicBounds(drawableLeft, drawableTop, drawableRight, drawableBottom);

    }

    /**
     * RadioButton上、下、左、右设置图标
     */
    public void setCompoundDrawablesWithIntrinsicBounds(Drawable left, Drawable top, Drawable right, Drawable bottom) {

        if (left != null) {
            left.setBounds(0, 0, mDrawableSize, mDrawableSize);
        }
        if (right != null) {
            right.setBounds(0, 0, mDrawableSize, mDrawableSize);
        }
        if (top != null) {
            top.setBounds(0, 0, mDrawableSize, mDrawableSize);
        }
        if (bottom != null) {
            bottom.setBounds(0, 0, mDrawableSize, mDrawableSize);
        }
        setCompoundDrawables(left, top, right, bottom);
    }

}

2.在style.xml文件中加入

3.加入属性参数，在values文件夹下新建attrs.xml文件，并加入

4.在布局中引用

    

    

            //设置资源

        

        

        

        

    

Demo地址：https://github.com/yechaoa/RadioButtonDemo