自定义drawable大小可控的textview

textview 可以在上下左右添加一个drawable，在布局文件中作如下设置：

但是如果任意尺寸图片，显示的效果就如下图所示：

image.png

如果要控制图片的大小(假如设置图片长宽为20dp)，一般就要在代码中设置：

        TextView textView = findViewById(R.id.text);
        Drawable drawable = getResources().getDrawable(R.mipmap.ic_launcher);
        drawable.setBounds(0, 0, dp2px(20), dp2px(20));
        textView.setCompoundDrawables(drawable, null, null, null);

图片效果如下：

image.png

如果这种方式操作起来麻烦，可以自定义textview。

可以重写textview设置drawable大小方法，再增加自定义图片大小的属性，就可以在布局文件中设置了。代码如下：
自定义图片大小属性

public class TextViewDrawable extends android.support.v7.widget.AppCompatTextView {
    private static final int DIRECTION_WIDTH = 0;
    private static final int DIRECTION_HEIGHT = 1;
    private float drawableWidth;
    private float drawableHeight;
    private static final String TAG = TextViewDrawable.class.getSimpleName();

    public TextViewDrawable(Context context) {
        this(context, null);
    }

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

    }

    public TextViewDrawable(Context context, @Nullable AttributeSet attrs, int defStyleAttr) {
        super(context, attrs, defStyleAttr);
        TypedArray array = context.obtainStyledAttributes(attrs, R.styleable.TextViewDrawable);
        drawableWidth = array.getDimension(R.styleable.TextViewDrawable_drawable_width, 0);
        drawableHeight = array.getDimension(R.styleable.TextViewDrawable_drawable_height, 0);
        array.recycle();
        if (drawableWidth > 0 && drawableHeight > 0) {
            Drawable[] drawables = getCompoundDrawables();
            setCompoundDrawablesWithIntrinsicBounds(drawables[0], drawables[1], drawables[2], drawables[3]);
        }
    }

    @Override
    public void setCompoundDrawablesWithIntrinsicBounds(@Nullable Drawable left, @Nullable Drawable top, @Nullable Drawable right, @Nullable Drawable bottom) {
        if (left != null) {
            left.setBounds(0, 0, getSize(left, DIRECTION_WIDTH),
                    getSize(left, DIRECTION_HEIGHT));
        }
        if (right != null) {
            right.setBounds(0, 0, getSize(right, DIRECTION_WIDTH),
                    getSize(right, DIRECTION_HEIGHT));
        }
        if (top != null) {
            top.setBounds(0, 0, getSize(top, DIRECTION_WIDTH),
                    getSize(top, DIRECTION_HEIGHT));
        }
        if (bottom != null) {
            bottom.setBounds(0, 0, getSize(bottom, DIRECTION_WIDTH),
                    getSize(bottom, DIRECTION_HEIGHT));
        }
        setCompoundDrawables(left, top, right, bottom);
    }
    //获取图片的宽高
    private int getSize(Drawable drawable, int direction) {
        if (drawableWidth > 0 && drawableHeight > 0) {
            if (direction == DIRECTION_WIDTH) {
                return (int) drawableWidth;
            } else {
                return (int) drawableHeight;
            }
        } else {
            if (direction == DIRECTION_WIDTH) {
                return drawable.getIntrinsicWidth();
            } else {
                return drawable.getIntrinsicHeight();
            }
        }
    }
}

实际效果如下图：

image.png

对应的布局文件：