Android 中自定义属性(attr.xml,TypedArray)的使用
一、 在res/values 文件下定义一个attrs.xml 文件.代码如下:
<?xml version="1.0" encoding="utf-8"?> <resources> <declare-styleable name="MyView"> <attr name="textColor" format="color" /> <attr name="textSize" format="dimension" /> </declare-styleable> </resources>
public MyView(Context context,AttributeSet attrs) { super(context,attrs); mPaint = new Paint(); TypedArray a = context.obtainStyledAttributes(attrs, R.styleable.MyView); int textColor = a.getColor(R.styleable.MyView_textColor, 0XFFFFFFFF); float textSize = a.getDimension(R.styleable.MyView_textSize, 36); mPaint.setTextSize(textSize); mPaint.setColor(textColor); a.recycle(); }
package cn.elingwange.android.test.styleable; import android.content.Context;... public class MyView extends View { private Paint mPaint; private Context mContext; private static final String mString = "Welcome to elingwange's blog"; public MyView(Context context) { super(context); mPaint = new Paint(); } public MyView(Context context,AttributeSet attrs) { super(context,attrs); mPaint = new Paint(); TypedArray a = context.obtainStyledAttributes(attrs, R.styleable.MyView); int textColor = a.getColor(R.styleable.MyView_textColor, 0XFFFFFFFF); float textSize = a.getDimension(R.styleable.MyView_textSize, 36); mPaint.setTextSize(textSize); mPaint.setColor(textColor); a.recycle(); } @Override protected void onDraw(Canvas canvas) { // TODO Auto-generated method stub super.onDraw(canvas); //设置填充 mPaint.setStyle(Style.FILL); //画一个矩形,前俩个是矩形左上角坐标,后面俩个是右下角坐标 canvas.drawRect(new Rect(10, 10, 100, 100), mPaint); mPaint.setColor(Color.BLUE); //绘制文字 canvas.drawText(mString, 10, 110, mPaint); } }
<?xml version="1.0" encoding="utf-8"?> <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" xmlns:elingwange="http://schemas.android.com/apk/res/cn.elingwange.android.test.styleable" android:orientation="vertical" android:layout_width="fill_parent" android:layout_height="fill_parent" > <cn.elingwange.android.test.styleable.MyView android:layout_width="fill_parent" android:layout_height="fill_parent" elingwange:textSize="20px" elingwange:textColor="#fff" /> </LinearLayout>