感觉，注释比源码精彩！直接拿到项目里试试吧，方便、高效、减少布局层级！
1.源码以及注释
/**
*
* TextView的setCompoundDrawables()可以在其四周设置图片，但是有个众所周知的问题，即无法设置drawable大小。
* 这就导致在实际的使用中有很大的局限性，必须用代码去控制，就略显麻烦了。
*
* 这个自定义控件虽然简单，也非常不起眼，但是用处还真不少：
* 1.解决了主要矛盾，无法在布局里设置TextView图片大小问题，使用更加简单。
* 除了设置图片大小，其它的TextView可以的事情这个一样也都可以
*
* 2.图片加文字的简单组合非常常见，原本为了适配图片大小不得不用一个xxxLayout＋ImageView+TextView
* 才能搞定的事，现在用一个控件即可搞定。
* 在方便、高效使用的同时，也有效的减少了布局层。===》千万不要瞧不上这点苍蝇肉
*
* 原理真的简单到只有两句话：
* 1.通过Drawable的setBound()设置显示区域，也就是图片大小
* 2.通过TextView的setCompoundDrawables()设置要显示的图片
*
* 高能预警：
* 在网上看到有一个版本，在控件的onMeasure()设置Drawable.setBound(), 在onDraw()里设置 setCompoundDrawables()。
* 看setCompoundDrawables()源码可以知道，这个方法最终会调用invalide()和requestLayout()，会导致严重的后果就是，
* onMeasure()和onDraw()会无限循环的互调下去，有点浪费
*/
public class DrawableTextView extends TextView{
public DrawableTextView(Context context) {
super(context);
}
public DrawableTextView(Context context, AttributeSet attrs) {
super(context, attrs);
init(context, attrs);
}
public DrawableTextView(Context context, AttributeSet attrs, int defStyleAttr) {
super(context, attrs, defStyleAttr);
init(context, attrs);
}
private void init(Context context, AttributeSet attrs) {
TypedArray ta = context.obtainStyledAttributes(attrs, R.styleable.DrawableTextView);
int width = ta.getDimensionPixelOffset(R.styleable.DrawableTextView_drawable_width, -1);
int height = ta.getDimensionPixelOffset(R.styleable.DrawableTextView_drawable_height, -1);
SizeWrap sizeWrap = new SizeWrap();
Drawable leftDrawable = ta.getDrawable(R.styleable.DrawableTextView_left_drawable);
if (leftDrawable != null) {
int lwidth = ta.getDimensionPixelOffset(R.styleable.DrawableTextView_leftdrawable_width, -1);
int lheight = ta.getDimensionPixelOffset(R.styleable.DrawableTextView_lefttdrawable_height, -1);
if (sizeWrap.checkWidthAndHeight(width, height, lwidth, lheight)) {
leftDrawable.setBounds(0, 0, sizeWrap.width, sizeWrap.height);
} else {
throw new IllegalArgumentException("error left drawable size setting");
}
}
Drawable rightDrawable = ta.getDrawable(R.styleable.DrawableTextView_right_drawable);
if (rightDrawable != null) {
int rwidth = ta.getDimensionPixelOffset(R.styleable.DrawableTextView_rightdrawable_width, -1);
int rheight = ta.getDimensionPixelOffset(R.styleable.DrawableTextView_rightdrawable_height, -1);
if (sizeWrap.checkWidthAndHeight(width,height, rwidth, rheight)) {
rightDrawable.setBounds(0, 0, sizeWrap.width, sizeWrap.height);
} else {
throw new IllegalArgumentException("error right drawable size setting");
}
}
Drawable topDrawable = ta.getDrawable(R.styleable.DrawableTextView_top_drawable);
if (topDrawable != null) {
int twidth = ta.getDimensionPixelOffset(R.styleable.DrawableTextView_topdrawable_width, -1);
int theight = ta.getDimensionPixelOffset(R.styleable.DrawableTextView_topdrawable_height, -1);
if (sizeWrap.checkWidthAndHeight(width,height, twidth, theight)) {
topDrawable.setBounds(0, 0, sizeWrap.width, sizeWrap.height);
} else {
throw new IllegalArgumentException("error top drawable size setting");
}
}
Drawable bottomDrawable = ta.getDrawable(R.styleable.DrawableTextView_bottom_drawable);
if (bottomDrawable != null) {
int bwidth = ta.getDimensionPixelOffset(R.styleable.DrawableTextView_bottomdrawable_width, -1);
int bheight = ta.getDimensionPixelOffset(R.styleable.DrawableTextView_bottomdrawable_height, -1);
if (sizeWrap.checkWidthAndHeight(width, height, bwidth, bheight)) {
bottomDrawable.setBounds(0, 0, sizeWrap.width, sizeWrap.height);
} else {
throw new IllegalArgumentException("error bottom drawable size setting");
}
}
this.setCompoundDrawables(leftDrawable, topDrawable, rightDrawable, bottomDrawable);
ta.recycle();
ta = null;
}
/**
*
*/
public static class SizeWrap {
int width;
int height;
public boolean checkWidthAndHeight(int globalWidth, int globalHeight, int localWidth, int localHeight) {
width = 0;
height = 0;
//局部的大小设置均正常的情况
if (localWidth > 0 && localHeight > 0) {
width = localWidth;
height = localHeight;
return true;
}
//局部大小没设置时，看全局的大小是否正确设置
if (localWidth == -1 && localHeight == -1) {
if (globalWidth > 0 && globalHeight > 0) {
width = globalWidth;
height = globalHeight;
return true;
}
}
return false;
}
}
}
2. attrs.xml中的自定义属性
<declare-styleable name="DrawableTextView">
<attr name="left_drawable" format="reference"/>
<attr name="right_drawable" format="reference"/>
<attr name="top_drawable" format="reference"/>
<attr name="bottom_drawable" format="reference"/>
<attr name="drawable_width" format="dimension"/>
<attr name="drawable_height" format="dimension"/>
<attr name="leftdrawable_width" format="dimension"/>
<attr name="lefttdrawable_height" format="dimension"/>
<attr name="rightdrawable_width" format="dimension"/>
<attr name="rightdrawable_height" format="dimension"/>
<attr name="topdrawable_width" format="dimension"/>
<attr name="topdrawable_height" format="dimension"/>
<attr name="bottomdrawable_width" format="dimension"/>
<attr name="bottomdrawable_height" format="dimension"/>
</declare-styleable>
3. 使用示例
在布局文件根布局下定义好app命名空间，
xmlns:app="http://schemas.android.com/apk/res-auto"
<com.example.xxx.myapplication.view.DrawableTextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:clickable="true"
android:text="首页"
android:background="@drawable/bg_select"
app:left_drawable="@drawable/image"
app:right_drawable="@drawable/dca99cdd9a9270e77ae6bb62bd80ca"
app:bottom_drawable="@drawable/a201609025013"
android:gravity="center"
app:drawable_width="50px"
app:drawable_height="50px"
app:rightdrawable_width="20px"
app:rightdrawable_height="20px"
android:paddingRight="10dp"
android:paddingLeft="10dp"
android:paddingTop="5dp"
android:paddingBottom="5dp"
android:drawablePadding="5dp"/>
