Android中自定义属性（attrs.xml，TypedArray）的使用

来源：互联网发布：淘宝失踪儿童在哪里编辑：程序博客网时间：2024/05/21 06:42

该实例是在自定义View上使用自定义属性的。

MyView.java

package com.adnroid.test;     import com.adnroid.test.R;     import android.content.Context;  import android.content.res.TypedArray;  import android.graphics.Canvas;  import android.graphics.Color;  import android.graphics.Paint;  import android.graphics.Rect;  import android.graphics.Paint.Style;  import android.util.AttributeSet;  import android.view.View;     public class MyView extends View {      private Paint myPaint;      private static final String myString = "Welcome to our Zoon!";         public MyView(Context context) {          super(context);          // TODO Auto-generated constructor stub       }             public MyView(Context context, AttributeSet attr) {          super(context, attr);           myPaint = new Paint();           TypedArray a = context.obtainStyledAttributes(attr, R.styleable.myView);//TypedArray是一个数组容器          float textSize = a.getDimension(R.styleable.myView_textSize, 30);//防止在XML文件里没有定义，就加上了默认值30          int textColor = a.getColor(R.styleable.myView_textColor, 0xFFFFFFFF);//同上,这里的属性是:名字_属性名           myPaint.setTextSize(textSize);           myPaint.setColor(textColor);           a.recycle();//我的理解是：返回以前取回的属性，供以后使用。以前取回的可能就是textSize和textColor初始化的那段       }      @Override     protected void onDraw(Canvas canvas) {          // TODO Auto-generated method stub          super.onDraw(canvas);          //myPaint = new Paint();           myPaint.setColor(Color.RED);           myPaint.setStyle(Style.FILL);                      canvas.drawRect(new Rect(10,10,100,100), myPaint);           myPaint.setColor(Color.WHITE);           canvas.drawText(myString, 10, 100, myPaint);       }     }

attrs.xml

<?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>

main.xml

<?xml version="1.0" encoding="utf-8"?>  <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"     xmlns:test="http://schemas.android.com/apk/res/com.adnroid.test"     android:orientation="vertical"     android:layout_width="fill_parent"     android:layout_height="fill_parent"     >  <TextView       android:layout_width="fill_parent"      android:layout_height="wrap_content"      android:text="@string/hello"     />  <com.adnroid.test.MyView     android:layout_width="fill_parent"     android:layout_height="fill_parent"     test:textSize="10px"     test:textColor="#fff"     />  </LinearLayout>

0 0