自定义属性

<?xml version="1.0" encoding="utf-8"?><resources>   <!--定义名字叫MyView属性集合-->    <declare-styleable name="MyView">        <!--定义一个名字叫my_name并且类型是string的属性-->        <attr name="my_name" format="string"/>        <attr name="my_age" format="integer"/>        <attr name="my_bg" format="reference|color"/>    </declare-styleable></resources>

<com.example.makura.myapplication.MyView    mydiyattr:my_age="100"    mydiyattr:my_name="zhangsan"    mydiyattr:my_bg="@drawable/testimg"    android:layout_width="match_parent"    android:layout_height="match_parent" />

public class MyView extends View {    private int myAge;    private String myName;    private Bitmap myBg;    public MyView(Context context, @Nullable AttributeSet attrs) {        super(context, attrs);        /**         * 获取属性的3种方式         * 1.用命名空间去获取         * 2.遍历属性集合         * 3.使用系统工具，获取属性         */        // 第一种        String name = attrs.getAttributeValue("http://schemas.android.com/apk/res-auto", "my_name");        String age = attrs.getAttributeValue("http://schemas.android.com/apk/res-auto", "my_age");        String bg = attrs.getAttributeValue("http://schemas.android.com/apk/res-auto", "my_bg");        Log.e("name = ", name);        Log.e("age = ", age);        Log.e("bg = ", bg);        Log.e("分割线1", "-----------------------");        // 第二种        for (int i = 0; i < attrs.getAttributeCount(); i++) {            String attributeName = attrs.getAttributeName(i);            String attributeValue = attrs.getAttributeValue(i);            Log.e(attributeName + " == ", attributeValue);        }        Log.e("分割线2", "-----------------------");        // 第三种        TypedArray typedArray = context.obtainStyledAttributes(attrs, R.styleable.MyView);        for (int i = 0; i < typedArray.getIndexCount(); i++) {            int index = typedArray.getIndex(i);            switch (index) {                case R.styleable.MyView_my_name:                    myName = typedArray.getString(index);                    break;                case R.styleable.MyView_my_age:                    myAge = typedArray.getInt(index,0);                    break;                case R.styleable.MyView_my_bg:                    Drawable drawable = typedArray.getDrawable(i);                    BitmapDrawable bd = (BitmapDrawable) drawable;                    myBg = bd.getBitmap();                    break;            }        }        //回收        typedArray.recycle();    }    @Override    protected void onDraw(Canvas canvas) {        super.onDraw(canvas);        Paint paint = new Paint();        paint.setColor(Color.RED);        paint.setTextSize(30);        canvas.drawBitmap(myBg,0,0,paint);        canvas.drawText("myName is"+myName+" myage="+myAge,150,150,paint);    }}