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                        /移动开发
                        
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                        /Android UI模板设计

使用com.example.nate.mytopbar.Topbar之后报错

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="   
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"    
android:layout_height="match_parent" 
android:paddingBottom="@dimen/activity_vertical_margin"    
android:paddingLeft="@dimen/activity_horizontal_margin"    
android:paddingRight="@dimen/activity_horizontal_margin"    
android:paddingTop="@dimen/activity_vertical_margin"    
tools:context=".MainActivity">
    <com.example.nate.mytopbar.Topbar        
android:id="@+id/topbar"        
android:layout_width="match_parent"        
android:layout_height="40dp"  
app:LeftBackground="@drawable/blue_color"       
app:LeftText="Back"      
app:LeftTextColor="#FFFFFF"    
app:rightBackground="@drawable/blue_color"
app:rightText="More"  
app:rightTextColor="#FFFFFF"      
app:title="自定义标题"      
app:titleColor="#123412"     
app:titleSize="10sp"
>
    </com.example.nate.mytopbar.Topbar>
</RelativeLayout>

package com.example.nate.mytopbar;

import android.content.Context;
import android.content.res.TypedArray;
import android.graphics.drawable.Drawable;
import android.util.AttributeSet;
import android.view.Gravity;
import android.view.ViewGroup;
import android.widget.Button;
import android.widget.RelativeLayout;
import android.widget.TextView;

public class Topbar extends RelativeLayout {
private Button leftbutton;
private Button rightbutton;
private TextView tvtitle;

private int leftcolor;
private Drawable leftbackground;
private String lefttext;

private int rightcolor;
private Drawable rightbackground;
private String righttext;

private int titlecolor;
private float titlesize;
private String titletext;

private LayoutParams leftparams,rightparams,titleparams;

public Topbar(Context context, AttributeSet attrs) {
super(context, attrs);

//拿到自己定义的属性
TypedArray ta=context.obtainStyledAttributes(attrs,R.styleable.Topbar );
leftcolor=ta.getColor(R.styleable.Topbar_LeftTextColor,0);
leftbackground=ta.getDrawable(R.styleable.Topbar_LeftBackground);
lefttext=ta.getString(R.styleable.Topbar_LeftText);

rightcolor=ta.getColor(R.styleable.Topbar_rightTextColor,0);
rightbackground=ta.getDrawable(R.styleable.Topbar_rightBackground);
righttext=ta.getString(R.styleable.Topbar_rightText);

titlecolor=ta.getColor(R.styleable.Topbar_titleColor,0);
titlesize=ta.getDimension(R.styleable.Topbar_titleSize,0);
titletext=ta.getString(R.styleable.Topbar_title);

//回收 1.防止浪费资源 2.避免由于一些值的缓存发生错误
ta.recycle();

//创建控件
leftbutton=new Button(context);//context上下文
rightbutton=new Button(context);
tvtitle=new TextView(context);

//为三个控件设置属性
rightbutton.setTextColor(rightcolor);
rightbutton.setBackground(rightbackground);
rightbutton.setText(righttext);

leftbutton.setTextColor(leftcolor);
leftbutton.setBackground(leftbackground);
leftbutton.setText(lefttext);

tvtitle.setText(titletext);
tvtitle.setTextColor(titlecolor);
tvtitle.setTextSize(titlesize);
tvtitle.setGravity(Gravity.CENTER);

//设置整体布局的背景颜色
setBackgroundColor(0xFFF59563);

//为左布局参数，第一属性宽，第二属性高
leftparams=new LayoutParams(LayoutParams.WRAP_CONTENT,LayoutParams.WRAP_CONTENT);
leftparams.addRule(RelativeLayout.ALIGN_PARENT_LEFT,TRUE);//相对父类左对齐

//添加控件到viewgroup中
addView(leftbutton,leftparams);

rightparams=new LayoutParams(ViewGroup.LayoutParams.WRAP_CONTENT,ViewGroup.LayoutParams.WRAP_CONTENT);
rightparams.addRule(RelativeLayout.ALIGN_PARENT_RIGHT,TRUE);

addView(rightbutton,rightparams);

titleparams=new LayoutParams(ViewGroup.LayoutParams.WRAP_CONTENT, ViewGroup.LayoutParams.MATCH_PARENT);
titleparams.addRule(RelativeLayout.CENTER_IN_PARENT,TRUE);

addView(tvtitle,titleparams);

}
}

<?xml version="1.0" encoding="utf-8"?>
<resources>
<declare-styleable name="Topbar">
<attr name="title" format="string"/>
<attr name="titleSize" format="dimension"/>
<attr name="titleColor" format="color"/>
<attr name="LeftText" format="string"/>
<attr name="LeftTextColor" format="color"/>
<attr name="LeftBackground" format="reference|color"/>
<attr name="rightText" format="string"/>
<attr name="rightTextColor" format="color"/>
<attr name="rightBackground" format="reference|color"/>
</declare-styleable>
</resources>

错误如图：