android自定义view属性

方法一：

MyView.class

package com.bwie.view;

import android.content.Context;
import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.Paint;
import android.util.AttributeSet;
import android.view.View;

public class MyView extends View {
	
	private int radius;
	private final static String NAMESPACE = "aaa1407a";

	public MyView(Context context, AttributeSet attrs) {
		super(context, attrs);
		// TODO Auto-generated constructor stub
		radius = attrs.getAttributeIntValue(NAMESPACE, "radius", 0);
	}
	@Override
	protected void onDraw(Canvas canvas) {
		// TODO Auto-generated method stub
		super.onDraw(canvas);
		Paint paint=new Paint();
		paint.setColor(Color.CYAN);
		
		canvas.drawCircle(getWidth()/2, getHeight()/2, radius, paint);
	}

}

 xml

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    xmlns:myattr="aaa1407a"
     android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context=".MainActivity" >

    <com.bwie.view.MyView
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_centerHorizontal="true"
        android:layout_centerVertical="true"
        myattr:radius="200" />

</RelativeLayout>

attrs

<?xml version="1.0" encoding="utf-8"?>
<resources>
    <declare-styleable name="MyView">
        <attr name="radius" format="integer"/>
        <attr name="mycolor" format="reference|color"/>
    </declare-styleable>
    
</resources>

方法二：

MyView.class

package com.bwie.view;

import android.content.Context;
import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.Paint;
import android.util.AttributeSet;
import android.view.View;

public class MyView extends View {
    
    private int radius;
public MyView(Context context, AttributeSet attrs) {
        super(context, attrs);
        // TODO Auto-generated constructor stub

　　//获得自定义的属性，即获得自定义的半径
    TypedArray a = context.obtainStyledAttributes(attrs, R.styleable.MyView);
    radius=a.getInt(R.styleable.MyView_radius, 0);
        
    }
    @Override
    protected void onDraw(Canvas canvas) {
        // TODO Auto-generated method stub
        super.onDraw(canvas);
        Paint paint=new Paint();
        paint.setColor(Color.CYAN);
        
        canvas.drawCircle(getWidth()/2, getHeight()/2, radius, paint);
    }

}

xml

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    xmlns:myattr="http://schemas.android.com/apk/res/com.bwie.test"//主包名
   	android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context=".MainActivity" >

    <com.bwie.view.MyView
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_centerHorizontal="true"
        android:layout_centerVertical="true"
        myattr:radius="200" />

</RelativeLayout>

 attrs

<?xml version="1.0" encoding="utf-8"?>
<resources>
    <declare-styleable name="MyView">
        <attr name="radius" format="integer"/>
        <attr name="mycolor" format="reference|color"/>
    </declare-styleable>
    
</resources>