Android自定义属性的使用示例

MainActivity如下:

package cc.testattrs;    import android.os.Bundle;  import android.app.Activity;    public class MainActivity extends Activity {     @Override   protected void onCreate(Bundle savedInstanceState) {    super.onCreate(savedInstanceState);    setContentView(R.layout.main);   }  }

ViewSubclass如下:

package cc.testattrs;    import android.content.Context;  import android.content.res.TypedArray;  import android.graphics.Canvas;  import android.graphics.Color;  import android.graphics.Paint;  import android.graphics.Paint.Style;  import android.util.AttributeSet;  import android.view.View;  /**   * Demo描述：   * Android自定义属性的使用   *    * 注意事项:   * 1 在main.xml中声明命名空间   *   xmlns:testattr="http://schemas.android.com/apk/res/cc.testattrs"   *   其中http://schemas.android.com/apk/res/为固定写法,其后追加包名   *   testattr为我们给自定义属性的别名引用   * 2 getDimension(R.styleable.TestAttr_testTextSize, 20);   *   第二个参数意思是:假如在xml文件中没有为改属性设值则采用此值.   *   其余getXX()方法均类似   * 3 注意getColor()方法中第二个参数的取值,是一个颜色值,在这里很容易错误   *   */  public class ViewSubclass extends View {      private Paint mPaint;      private float textSize;      private int textColor ;   public ViewSubclass(Context context, AttributeSet attrs, int defStyle) {    super(context, attrs, defStyle);   }     public ViewSubclass(Context context, AttributeSet attrs) {    super(context, attrs);    mPaint = new Paint();    TypedArray typedArray = context.obtainStyledAttributes(attrs,R.styleable.TestAttr);    textSize = typedArray.getDimension(R.styleable.TestAttr_testTextSize, 20);    textColor = typedArray.getColor(R.styleable.TestAttr_testColor, Color.BLACK);    System.out.println("textSize="+textSize+",textColor="+textColor);    mPaint.setTextSize(textSize);    mPaint.setColor(textColor);    //切记recycle()    typedArray.recycle();   }     public ViewSubclass(Context context) {    super(context);   }         @Override      protected void onDraw(Canvas canvas) {       super.onDraw(canvas);       mPaint.setStyle(Style.FILL);         canvas.drawText("9527", 10, 20, mPaint);      }     }

main.xml如下:

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"      xmlns:testattr="http://schemas.android.com/apk/res/cc.testattrs"      xmlns:tools="http://schemas.android.com/tools"      android:layout_width="match_parent"      android:layout_height="match_parent"      tools:context=".MainActivity"     >        <cc.testattrs.ViewSubclass          android:layout_width="200dip"          android:layout_height="200dip"          android:layout_centerInParent="true"           testattr:testTextSize="10dip"          testattr:testColor="#ff0000"      />    </RelativeLayout>

attrs.xml如下:

<?xml version="1.0" encoding="utf-8"?>  <resources>        <declare-styleable name="TestAttr">          <attr name="testTextSize" format="dimension"/>          <attr name="testColor" format="color"/>      </declare-styleable>  </resources>