android – 如何在解析的XML标签上检查Null值

目前我正在构建这个 Android应用程序,让我难以理解的一件事就是处理ListView项目全部以我需要的顺序显示但是如果一个标签有一个空白值它显示为singleLine对象只占用空间和间距出布局.

此图像ListView项目中的所有空间都是一个正在发送的空字符串,我将其解析.
我想简单地知道处理这个错误的最佳方法吗？

我的ListView项目的XML：

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

    <TextView
        android:id="@+id/ContactTitle"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignParentLeft="true"
        android:layout_alignParentTop="true"
        android:textAppearance="?android:attr/textAppearanceMedium"
        android:textColor="@color/White" />

    <TextView
        android:id="@+id/Name"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignRight="@+id/ContactTitle"
        android:layout_below="@+id/ContactTitle"
        android:layout_marginRight="17dp"
        android:textColor="@color/White" />

    <TextView
        android:id="@+id/MainPhone"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignRight="@+id/Name"
        android:layout_below="@+id/Name"
        android:textColor="@color/White"/>

    <TextView
        android:id="@+id/Cell"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignRight="@+id/MainPhone"
        android:layout_below="@+id/MainPhone"
        android:textColor="@color/White" />

    <TextView
        android:id="@+id/Fax"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignLeft="@+id/Cell"
        android:layout_below="@+id/Cell"
        android:textColor="@color/White" />

    <TextView
        android:id="@+id/Email"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignLeft="@+id/Fax"
        android:layout_below="@+id/Fax"
        android:ellipsize="marquee"
        android:textColor="@color/EmailColor" />

</RelativeLayout>

我需要检查Empty TextViews并隐藏它们.
我的代码在这里：

protected void onPostExecute(String result) {
            String xml = result;
            String KEY_ITEM = "Contact";
            String KEY_CONTACTTITLE = "ContactTitle";
            String KEY_NAME = "Name";
            String KEY_MAINPHONE = "Phone";
            String KEY_CELLPHONE = "Cell";
            String KEY_FAX = "Fax";
            String KEY_EMAIL = "Email";
            ArrayList<HashMap<String, String>> menuItems = new ArrayList<HashMap<String, String>>();

            Document doc = getDomElement(xml);
            if (xml != null) {
                {
                    NodeList nl = doc.getElementsByTagName(KEY_ITEM);
                    for (int i = 0; i < nl.getLength(); i++) {
                        HashMap<String, String> map = new HashMap<String, String>();
                        Element e = (Element) nl.item(i);
                        if (getValue(e, KEY_CONTACTTITLE) != null) {
                            map.put(KEY_CONTACTTITLE,
                                    getValue(e, KEY_CONTACTTITLE));
                        } else {
                            TextView contactTitle = (TextView) findViewById(R.id.ContactTitle);
                        }
                        if (getValue(e, KEY_NAME) != null) {
                            map.put(KEY_NAME, getValue(e, KEY_NAME));
                        }
                        if (getValue(e, KEY_MAINPHONE) != null) {
                            map.put(KEY_MAINPHONE, getValue(e, KEY_MAINPHONE));
                        }

                        if (getValue(e, KEY_CELLPHONE) != null) {
                            map.put(KEY_CELLPHONE, getValue(e, KEY_CELLPHONE));
                        }

                        if (getValue(e, KEY_FAX) != null) {
                            map.put(KEY_FAX, getValue(e, KEY_FAX));
                        }

                        if (getValue(e, KEY_EMAIL) != null) {
                            map.put(KEY_EMAIL, getValue(e, KEY_EMAIL));
                        }

                        menuItems.add(map);
                        menuItems = simple;
                    }

                    String[] hashMapObjects = { KEY_CONTACTTITLE, KEY_NAME,
                            KEY_MAINPHONE, KEY_CELLPHONE, KEY_FAX, KEY_EMAIL };
                    int[] listItemObjects = { R.id.ContactTitle, R.id.Name,
                            R.id.MainPhone, R.id.Cell, R.id.Fax, R.id.Email };

                      ListAdapter adapter = new SimpleAdapter(
                      MoveContactsActivity.this, menuItems,
                      R.layout.listed_contacts, hashMapObjects,
                      listItemObjects);
                     setListAdapter(adapter);

我正在尝试检查值是否为null以将对象添加到HashMap.这当然不起作用,我想知道如何检查那些空TextViews并隐藏它们.

如果TextView中没有显示任何内容,则只需调用View.setVisibility(View.GONE).由于您使用的是SimpleAdapter并且没有自定义的getView方法,因此最简单的方法是使用 SimpleAdapter.ViewBinder：

String[] hashMapObjects = { 
        KEY_CONTACTTITLE, KEY_NAME, KEY_MAINPHONE, KEY_CELLPHONE, KEY_FAX, KEY_EMAIL 
};

int[] listItemObjects = { 
        R.id.ContactTitle, R.id.Name, R.id.MainPhone, R.id.Cell, R.id.Fax, R.id.Email 
};

SimpleAdapter adapter = new SimpleAdapter(MoveContactsActivity.this, menuItems, R.layout.listed_contacts, hashMapObjects, listItemObjects);
SimpleAdapter.ViewBinder binder = new SimpleAdapter.ViewBinder() {
    @Override
    public boolean setViewValue(View view, Object object, String value) {
        if (!(view instanceof TextView)) {
            return false;
        }

        final TextView text = (TextView) view;

        text.setVisibility(TextUtils.isEmpty(value) ? View.GONE : View.VISIBLE);
        text.setText(value);

        return true;
    }
};

adapter.setViewBinder(binder);
setListAdapter(adapter);