Question

我正在尝试在现有View中添加自定义XML属性

将它们添加到自定义视图并不是一件大事，但我不知道如何在“基本”视图中访问这些属性（例如TextView，LinearLayout，ImageView ......）

当涉及片段和/或图书馆项目时，这将更加困难

到目前为止，这是我的代码

海关属性定义和XML（attrs.xml和布局）：

<?xml version="1.0" encoding="utf-8"?>
<resources>
<declare-styleable name="StarWars">
    <attr name="jedi" format="string" />
    <attr name="rank" format="string" />
</declare-styleable>

<LinearLayout
  xmlns:android="http://schemas.android.com/apk/res/android"
  xmlns:sw="http://schemas.android.com/apk/res-auto"
  android:layout_width="fill_parent"
  android:layout_height="fill_parent">

<TextView
    android:id="@+id/name"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:textSize="28dp"
    android:gravity="center_horizontal"
    sw:jedi="Obiwan" />

<TextView
    android:id="@+id/rank"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:textSize="28dp"
    android:gravity="center_horizontal"
    sw:rank="Master" />

由于我在片段上对此进行了充气（因此没有onCreate与attrs arg！），尝试获取2个sw自定义属性的唯一方法是：

将自定义LayoutInflater.Factory设置为onCreateView中的Fragment LayoutInflater

@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
  super.onCreateView(inflater, container, savedInstanceState);

  LayoutInflater layoutInflater = inflater.cloneInContext(inflater.getContext());
  layoutInflater.setFactory(new StarWarsLayoutFactory());

  View fragmentView = layoutInflater.inflate(R.layout.jedi, container, false);
  ((TextView) fragmentView.findViewById(android.R.id.jedi)).setText("Yep");

  return fragmentView;
}

尝试在自定义LayoutInflater.Factory上获取自定义属性：

public class StarWarsLayoutFactory implements Factory {
  @Override
  public View onCreateView(String name, Context context, AttributeSet attrs) {
              *** What to do here ? ***

      return null;
  }
}

有人有过这样的问题吗？

我在这里缺少什么？

Answer 1

我终于做到了这一点：）

你必须像在OP上一样创建一个新的LayoutInflater.Factory，但由于Factory用于所有膨胀的布局View，你必须在Factory.onCreateView上返回null（让Android处理通货膨胀）您必须在某处缓存自定义XML属性

所以这里解决方案：

您的布局XML视图必须具有和android：id
创建将保留自定义属性的类：

    public class AttributeParser {

    private AttributeParserFactory mFactory;
    private Map<Integer, HashMap<Integer, String>> mAttributeList;

    private class AttributeParserFactory implements LayoutInflater.Factory{
        @Override
        public View onCreateView(String name, Context context, AttributeSet attrs) {
            String id = attrs.getAttributeValue("http://schemas.android.com/apk/res/android", "id");

            if(id != null){
                // String with the reference character "@", so we strip it to keep only the reference
                id = id.replace("@", "");

                TypedArray libraryStyledAttributeList = context.obtainStyledAttributes(attrs, R.styleable.NewsHubLibrary);
                HashMap<Integer, String> libraryViewAttribute = new HashMap<Integer, String>();
                int i = 0;

                for(int attribute : R.styleable.NewsHubLibrary){
                    String attributeValue = libraryStyledAttributeList.getString(i);

                    if(attributeValue != null)
                        libraryViewAttribute.put(attribute, attributeValue);

                    i++;
                }

                if(!libraryViewAttribute.isEmpty())
                    mAttributeList.put(Integer.valueOf(id), libraryViewAttribute);

                libraryStyledAttributeList.recycle();
            }

            return null;
        }

    }

    public AttributeParser(){
        mAttributeList = new HashMap<Integer, HashMap<Integer, String>>();
        mFactory = new AttributeParserFactory();
    }

    public void clear() {
        mAttributeList.clear();
    }

    public LayoutInflater getLayoutInflater(LayoutInflater inflater) {
        clear();
        LayoutInflater layoutInflater = inflater.cloneInContext(inflater.getContext());
        layoutInflater.setFactory(mFactory);

        return layoutInflater;
    }

    public void setFactory(LayoutInflater inflater){
        inflater.cloneInContext(inflater.getContext()).setFactory(mFactory);
    }

    public void setViewAttribute(Activity activity) {
        for(Entry<Integer, HashMap<Integer, String>> attribute : mAttributeList.entrySet())
            if(activity.findViewById((Integer) attribute.getKey()) != null)
                activity.findViewById((Integer) attribute.getKey()).setTag(attribute.getValue());

    }

    public void setViewAttribute(View view) {
        for(Entry<Integer, HashMap<Integer, String>> attribute : mAttributeList.entrySet())
            if(view.findViewById((Integer) attribute.getKey()) != null)
                view.findViewById((Integer) attribute.getKey()).setTag(attribute.getValue());
    }

    public Map<Integer, HashMap<Integer, String>> getAttributeList() {
        return mAttributeList;
    }

    public void setAttributeList(Map<Integer, HashMap<Integer, String>> attributeList) {
        this.mAttributeList = attributeList;
    }
    }

使用AttributeParser时，您的自定义属性将存储在每个View标记中：

    LayoutInflater layoutInflater = mAttributeParser.getLayoutInflater(inflater);
    View view = layoutInflater.inflate(R.layout.jedi, null);
    mAttributeParser.setViewAttribute(view);

Answer 2

标准TextView等不会访问这些属性。您可以扩展它并提供包括读取这些自定义属性的功能。

TypedArray a = context.obtainStyledAttributes(attrs, R.styleable.StarWars, 0, 0);

String jedi = a.getText(R.styleable.StarWars_jedi);
String rank = a.getText(R.styleable.StarWars_rank);

a.recycle();

请务必在最后致电recycle()。

自定义XML属性，没有自定义View in Fragment

2 个答案: