Edit Text hints not appearing on later version SDK

问题

My app has been written for SDK 1.5 3.0 but when it is running on later versions the hints are not appearing in the EditText views. Any suggestions please? Cheers, Rick

Here is the xml layout code:

<?xml version="1.0" encoding="utf-8"?>
<ScrollView xmlns:android="http://schemas.android.com/apk/res/android"
  android:id="@+id/scrollView1"
  android:layout_width="fill_parent"
  android:layout_height="wrap_content" >

<LinearLayout
    android:layout_width="fill_parent"
    android:layout_height="wrap_content"
    android:background="#123456"
    android:gravity="center"
    android:orientation="vertical"
    android:padding="10dp" >

    <TextView
        android:id="@+id/warningTV"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_margin="5dp"
        android:gravity="center_horizontal"
        android:text="@string/warningTV"
        android:textColor="#FFFFFF"
        android:textSize="20sp"
        android:textStyle="bold" />

    <TextView
        android:id="@+id/csTitle"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_margin="2dp"
        android:text="@string/csTitle"
        android:textColor="#FFFFFF"
        android:textSize="20sp" />

    <EditText
        android:id="@+id/csET"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:layout_margin="5dp"
        android:textColor="#123456"
        android:gravity="center_horizontal"
        android:hint="@string/csET" 
        android:inputType="numberDecimal" />

    <TextView
        android:id="@+id/diaTitle"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_margin="2dp"
        android:text="@string/diaTitle"
        android:textColor="#FFFFFF"
        android:textSize="20dp" />

    <EditText
        android:id="@+id/diaET"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:layout_margin="5dp"
        android:gravity="center_horizontal"
        android:hint="@string/diaET"
        android:inputType="numberDecimal" />

    <TextView
        android:id="@+id/feedTitle"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_margin="2dp"
        android:text="@string/feedTitle"
        android:textColor="#FFFFFF"
        android:textSize="20dp" />

    <EditText
        android:id="@+id/feedET"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:layout_margin="5dp"
        android:gravity="center_horizontal"
        android:hint="@string/feedET"
        android:inputType="numberDecimal" >

        <requestFocus />
    </EditText>

    <TextView
        android:id="@+id/numTeeth"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_margin="2dp"
        android:text="@string/numTeeth"
        android:textColor="#FFFFFF"
        android:textSize="20dp" />

    <EditText
        android:id="@+id/teethET"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:layout_margin="5dp"
        android:gravity="center_horizontal"
        android:hint="@string/teethET"
        android:inputType="number" />

    <Button
        android:id="@+id/calcButton"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_margin="2dp"
        android:text="@string/calcButton"
        android:textColor="#123456"
        android:textSize="20sp"
        android:textStyle="bold" />

    <Button
        android:id="@+id/resetButton"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_margin="2dp"
        android:text="@string/resetButton"
        android:textColor="#123456"
        android:textSize="20sp"
        android:textStyle="bold" />
</LinearLayout>

</ScrollView>

You will notice that in the EditText I link to a string value for the hint. Strangely the hints only appear in early SDK but not later ones. This occurs in both the emulator and actual devices.

回答1:

I just answered a very similar question to this as well:

EditText hint not displaying

Here I believe your question has already been solved before, adding certain layouts to the element "EditText" such as "android:gravity="center_horizontal" may cause your problem:

How to add hint into EditText with inputType=“numberDecimal”?

Try removing that and wrap it in a layout that uses "android:gravity="center_horizontal" and put the "EditText" element inside.

Working example on StackOverflow:

Rows don't render properly in Android Layout. Buttons seem to be the problem

Doing a quick Google search here are some examples where people have gotten it to work:

The Android Tutorial Series Part 2 – Calculator App,

unit-testing-with-the-junit-testing-framework,

Android 4 - Apps Mortagage Calculator

I use Android 1.5 in order to make sure that all phones and tablets can run any application I create. Goodluck!

来源：https://stackoverflow.com/questions/9247195/edit-text-hints-not-appearing-on-later-version-sdk