如何添加自定义视图内的另一个自定义视图？ [英] How to add custom view inside another custom view?

问题描述

我想添加CustomViewBeta（扩展RelativeLayout的），以CustomViewAlpha（扩展的LinearLayout） - 的想法是，在CustomViewAlpha将举行一堆CustomViewBetas一拉一个ListView的。不管我怎么努力，这是行不通的。我不是什么也看不见 - 没有CustomViewBetas，也给了我一个NPE，当我尝试的setText在CustomViewBeta 里面的TextViews之一

CustomViewAlpha工作正常，因为它是硬codeD中的片段的XML：

 ＆LT; XML版本=1.0编码=UTF-8＆GT？;
＆LT;的FrameLayout
   ...＆GT;
    ＆LT; com.path.CustomViewAlpha
        机器人：ID =@ + ID / customviewalpha
        机器人：方向=垂直
        机器人：layout_gravity =center_vertical
        机器人：layout_width =match_parent
        机器人：layout_height =match_parent/＆GT;
＆LT; /的FrameLayout＆GT;
 

随着code是：

 公共类CustomViewAlpha扩展的LinearLayout {
私人语境mContext;

公共CustomViewAlpha（上下文的背景下）{
    超（上下文）;
    this.mContext =背景;
}

公共CustomViewAlpha（上下文的背景下，ATTRS的AttributeSet）{
    超（背景下，ATTRS）;
    this.mContext =背景;
}

公共CustomViewAlpha（上下文的背景下，ATTRS的AttributeSet，诠释defStyle）{
    超（背景下，ATTRS，defStyle）;
    this.mContext =背景;
}

公共无效addCustomViewBeta（字符串someString）{
    CustomViewBeta customViewBeta =新CustomViewBeta（mContext）;
    addView（customViewBeta）;
}
 

CustomViewBeta不硬codeD中的片段的XML和获得的编程方式添加：

公共类CustomViewBeta扩展RelativeLayout的{     民营背景mContext;

 私人的TextView TextView的;

公共CustomViewBeta（上下文的背景下）{
    超（上下文）;
    this.mContext =背景;
    在里面（）;
}

公共CustomViewBeta（上下文的背景下，ATTRS的AttributeSet）{
    超（背景下，ATTRS）;
    this.mContext =背景;
    在里面（）;
}

公共CustomViewBeta（上下文的背景下，ATTRS的AttributeSet，诠释defStyle）{
    超（背景下，ATTRS，defStyle）;
    this.mContext =背景;
    在里面（）;
}


私人无效的init（）{
    LayoutInflater.from（mContext）.inflate（R.layout.customviewbeta，空，假）;
    TextView的=（的TextView）findViewById（R.id.tripleexpandablelistview_category_name）;
    textView.setText（ASDASDASDAD）;
}
 

通过这个XML之中：

 ＆LT; XML版本=1.0编码=UTF-8＆GT？;
＆LT; com.path.CustomViewBeta
    的xmlns：机器人=htt​​p://schemas.android.com/apk/res/android
    机器人：layout_width =match_parent
    机器人：layout_height =WRAP_CONTENT＆GT;

    ＆LT;的TextView
        机器人：ID =@ + ID / customviewbeta_textview
        机器人：layout_width =WRAP_CONTENT
        机器人：layout_height =WRAP_CONTENT/＆GT;

＆LT; /com.path.CustomViewBeta>
 

我通常会用在textView.setText（ASDASDASDAD）一NPE击;线，因为TextView的为空。有我丢失的东西？如果我不尝试充气的CustomViewBeta一个XML，只是做编程（加入textviews逐个编程？）？谢谢你。

解决方案

你的初始化是错误的。

 私人无效的init（）{
    LayoutInflater.from（mContext）.inflate（R.layout.customviewbeta，空，假）;
    TextView的=（的TextView）findViewById（R.id.tripleexpandablelistview_category_name）;
    textView.setText（ASDASDASDAD）;
}
 

最后一个参数必须真添加的TextView 的RelativeLayout.Also 的ViewGroup ，有一个静态充气的方法，这样就可以避免 LayoutInflater.from（mContext），你可以叫膨胀（mContext，R.layout.customviewbeta，这一点）;

I'm trying to add CustomViewBeta (an extended RelativeLayout) to CustomViewAlpha (an extended LinearLayout) -- the idea being that the CustomViewAlpha will hold a bunch of CustomViewBetas a la a ListView. No matter what I try, it doesn't work. I either see nothing -- no CustomViewBetas, or it gives me an NPE when I try setText on one of the TextViews inside the CustomViewBeta

CustomViewAlpha works fine since it's hard-coded in the Fragment's XML:

<?xml version="1.0" encoding="utf-8"?>
<FrameLayout
   ...>
    <com.path.CustomViewAlpha
        android:id="@+id/customviewalpha"
        android:orientation="vertical"
        android:layout_gravity="center_vertical"
        android:layout_width="match_parent"
        android:layout_height="match_parent"/>
</FrameLayout>

With the code being:

public class CustomViewAlpha extends LinearLayout {
private Context mContext;

public CustomViewAlpha (Context context) {
    super(context);
    this.mContext = context;
}

public CustomViewAlpha (Context context, AttributeSet attrs) {
    super(context, attrs);
    this.mContext = context;
}

public CustomViewAlpha (Context context, AttributeSet attrs, int defStyle){
    super(context, attrs,defStyle);
    this.mContext = context;
}

public void addCustomViewBeta(String someString){
    CustomViewBeta customViewBeta = new CustomViewBeta(mContext);
    addView(customViewBeta);
}

CustomViewBeta is not hard-coded in the Fragment's XML and get's added programmatically:

public class CustomViewBeta extends RelativeLayout{ private Context mContext;

private TextView textView;

public CustomViewBeta (Context context) {
    super(context);
    this.mContext = context;
    init();
}

public CustomViewBeta (Context context, AttributeSet attrs) {
    super(context, attrs);
    this.mContext = context;
    init();
}

public CustomViewBeta (Context context, AttributeSet attrs, int defStyle){
    super(context, attrs,defStyle);
    this.mContext = context;
    init();
}


private void init() {
    LayoutInflater.from(mContext).inflate(R.layout.customviewbeta, null, false);
    textView = (TextView) findViewById(R.id.tripleexpandablelistview_category_name);
    textView.setText("ASDASDASDAD");
}

With this XML being:

<?xml version="1.0" encoding="utf-8"?>
<com.path.CustomViewBeta
    xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="wrap_content">

    <TextView
        android:id="@+id/customviewbeta_textview"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"/>

</com.path.CustomViewBeta>

I usually get hit with a NPE on the "textView.setText("ASDASDASDAD");" line because the TextView is null. Is there something I'm missing? Should I not try to inflate an XML for the CustomViewBeta and just do it programmatically (adding the textviews one by one programmatically?)? Thanks.

解决方案

your init is wrong

private void init() {
    LayoutInflater.from(mContext).inflate(R.layout.customviewbeta, null, false);
    textView = (TextView) findViewById(R.id.tripleexpandablelistview_category_name);
    textView.setText("ASDASDASDAD");
}

the last parameter has to be true to add the TextViewto the RelativeLayout.Also ViewGroup, has a static inflate method, so you can avoid LayoutInflater.from(mContext), you can just call inflate(mContext, R.layout.customviewbeta, this);

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