在我的应用程序中，我使用一个类在 TextInputLayout 下面显示实时字符数。这是课
public class CharacterCountErrorWatcher
implements TextWatcher
{
private final TextInputLayout mTextInputLayout;
private final ForegroundColorSpan mNormalTextAppearance;
private final ForegroundColorSpan mErrorTextAppearance;
/*private final AlignmentSpan mAlignmentSpan = new AlignmentSpan.Standard(Layout.Alignment.ALIGN_OPPOSITE);*/
private final AlignmentSpan mAlignmentSpan = new AlignmentSpan.Standard(Layout.Alignment.ALIGN_OPPOSITE);
private final SpannableStringBuilder mErrorText = new SpannableStringBuilder();
private int mMinLen;
private int mMaxLen;
public CharacterCountErrorWatcher(TextInputLayout textInputLayout, int minLen, int maxLen)
{
mTextInputLayout = textInputLayout;
mNormalTextAppearance = new ForegroundColorSpan(Color.GRAY);
mErrorTextAppearance=new ForegroundColorSpan(Color.RED);
mMinLen = minLen;
mMaxLen = maxLen;
updateErrorText();
}
private void updateErrorText()
{
mErrorText.clear();
mErrorText.clearSpans();
final int length = mTextInputLayout.getEditText().length();
if(length >= 0){
mErrorText.append(String.valueOf(length));
mErrorText.append(" / ");
mErrorText.append(String.valueOf(mMaxLen));
mErrorText.setSpan(mAlignmentSpan, 0, mErrorText.length(),
Spanned.SPAN_INCLUSIVE_EXCLUSIVE);
if(hasValidLength()){
mErrorText.setSpan(mNormalTextAppearance, 0, mErrorText.length(),
Spanned.SPAN_INCLUSIVE_EXCLUSIVE);
}
}
mTextInputLayout.setError(mErrorText);
}
public boolean hasValidLength()
{
final int length = mTextInputLayout.getEditText().length();
return (length >= mMinLen && length <= mMaxLen);
}
@Override
public void afterTextChanged(Editable s)
{
updateErrorText();
}
@Override
public void beforeTextChanged(CharSequence s, int start, int count, int after)
{
//
}
@Override
public void onTextChanged(CharSequence s, int start, int before, int count)
{
//
}
}
这就是我在 TextInputLayout 上设置此类的方式
text1.getEditText().addTextChangedListener(new CharacterCountErrorWatcher(text1, 0, 100));
更新
我的布局文件：
<?xml version="1.0" encoding="utf-8"?>
<FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:ppv="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:background="@color/logo_background"
tools:context="in.net.spectrum.frankstrade.SellActivity_2">
<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="vertical">
<android.support.design.widget.AppBarLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:theme="@style/ThemeOverlay.AppCompat.Dark.ActionBar">
<android.support.v7.widget.Toolbar
android:id="@+id/toolbar"
android:layout_width="match_parent"
android:layout_height="?attr/actionBarSize"
android:background="?attr/colorPrimary"
android:title="@string/app_name"
app:layout_scrollFlags="scroll|enterAlways"
app:popupTheme="@style/ThemeOverlay.AppCompat.Light" />
</android.support.design.widget.AppBarLayout>
<ScrollView
android:layout_width="match_parent"
android:layout_height="wrap_content">
<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_marginTop="10dp"
android:background="#F7F7F7"
android:focusableInTouchMode="true"
android:orientation="vertical"
android:padding="@dimen/activity_horizontal_margin"
android:weightSum="2">
<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_weight="1"
android:weightSum="2"
android:layout_marginBottom="10dp"
android:orientation="horizontal">
<ImageView
android:id="@+id/imv_camera"
android:layout_width="wrap_content"
android:layout_height="150dp"
android:layout_weight="1"
android:src="@drawable/camera" />
<ImageView
android:id="@+id/imv_gallery"
android:layout_width="wrap_content"
android:layout_height="150dp"
android:layout_weight="1"
android:src="@drawable/gallery" />
</LinearLayout>
<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_weight="1"
android:orientation="vertical">
<HorizontalScrollView
android:id="@+id/scroller"
android:layout_width="match_parent"
android:layout_height="wrap_content">
<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_gravity="center_vertical"
android:orientation="horizontal"
android:weightSum="2">
<LinearLayout
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginRight="5dp"
android:orientation="vertical">
<android.support.v7.widget.CardView
android:id="@+id/img_cv1"
android:visibility="gone"
android:layout_width="150dp"
android:layout_height="150dp"
android:layout_marginBottom="5dp"
android:layout_marginTop="5dp"
android:background="@color/colorCardView"
app:cardCornerRadius="5dp">
<ImageView
android:id="@+id/iv_photo1"
android:layout_width="150dp"
android:layout_height="150dp"
android:layout_marginRight="5dp"
android:padding="3dp"
android:background="@drawable/border" />
</android.support.v7.widget.CardView>
<ProgressBar
android:id="@+id/progress"
android:layout_width="150dp"
android:layout_height="30dp"
android:layout_gravity="bottom|center_horizontal"
android:indeterminate="true" />
</LinearLayout>
<LinearLayout
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginRight="5dp"
android:orientation="vertical">
<android.support.v7.widget.CardView
android:id="@+id/img_cv2"
android:layout_width="150dp"
android:layout_height="150dp"
android:layout_marginTop="5dp"
android:background="@color/colorCardView"
android:visibility="gone">
<ImageView
android:id="@+id/iv_photo2"
android:layout_width="150dp"
android:layout_height="150dp"
android:layout_marginRight="5dp"
android:padding="3dp"
android:background="@drawable/border" />
</android.support.v7.widget.CardView>
<ProgressBar
android:id="@+id/progress2"
android:layout_width="150dp"
android:layout_height="30dp"
android:layout_gravity="bottom|center_horizontal"
android:indeterminate="true" />
</LinearLayout>
<LinearLayout
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginRight="5dp"
android:orientation="vertical">
<android.support.v7.widget.CardView
android:id="@+id/img_cv3"
android:layout_width="150dp"
android:layout_height="150dp"
android:layout_marginTop="5dp"
android:background="@color/colorCardView"
android:visibility="gone">
<ImageView
android:id="@+id/iv_photo3"
android:layout_width="150dp"
android:layout_height="150dp"
android:layout_marginRight="5dp"
android:padding="3dp"
android:background="@drawable/border" />
</android.support.v7.widget.CardView>
<ProgressBar
android:id="@+id/progress3"
android:layout_width="150dp"
android:layout_height="30dp"
android:layout_gravity="bottom|center_horizontal"
android:indeterminate="true" />
</LinearLayout>
<LinearLayout
android:layout_marginRight="5dp"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:orientation="vertical">
<android.support.v7.widget.CardView
android:id="@+id/img_cv4"
android:layout_width="150dp"
android:layout_height="150dp"
android:layout_marginTop="5dp"
android:background="@color/colorCardView"
android:visibility="gone">
<ImageView
android:id="@+id/iv_photo4"
android:layout_width="150dp"
android:layout_height="150dp"
android:layout_marginRight="5dp"
android:padding="3dp"
android:background="@drawable/border" />
</android.support.v7.widget.CardView>
<ProgressBar
android:id="@+id/progress4"
android:layout_width="150dp"
android:layout_height="30dp"
android:layout_gravity="bottom|center_horizontal"
android:indeterminate="true" />
</LinearLayout>
<LinearLayout
android:layout_marginRight="5dp"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:orientation="vertical">
<android.support.v7.widget.CardView
android:id="@+id/img_cv5"
android:layout_width="150dp"
android:layout_height="150dp"
android:layout_marginTop="5dp"
android:background="@color/colorCardView"
android:visibility="gone">
<ImageView
android:id="@+id/iv_photo5"
android:layout_width="150dp"
android:layout_height="150dp"
android:layout_marginRight="5dp"
android:padding="3dp"
android:background="@drawable/border" />
</android.support.v7.widget.CardView>
</LinearLayout>
<ProgressBar
android:id="@+id/progress5"
android:layout_width="150dp"
android:layout_height="30dp"
android:layout_gravity="bottom|center_horizontal"
android:indeterminate="true" />
</LinearLayout>
</HorizontalScrollView>
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Add upto 5 images, each of max size 4 MB" />
<android.support.v7.widget.CardView
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_marginTop="5dp"
android:background="@color/colorCardView">
<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="vertical"
android:padding="@dimen/cardView_padding">
<TextView
android:id="@+id/txt_category"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_marginTop="15dp"
android:text="Select Category : "
android:textSize="@dimen/textSize" />
<Button
android:id="@+id/btn_category"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:textColor="@color/textColorPrimary"
android:textStyle="bold"
android:background="@drawable/button_background"
android:text="Select Category" />
<Spinner
android:id="@+id/sp_category"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_gravity="center_horizontal"
android:layout_marginTop="10dp"
android:background="@drawable/spinner_background"
android:spinnerMode="dialog" />
</LinearLayout>
</android.support.v7.widget.CardView>
<android.support.v7.widget.CardView
android:id="@+id/cv"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_marginTop="5dp"
android:background="@color/colorCardView">
<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="vertical"
android:padding="@dimen/cardView_padding">
<android.support.design.widget.TextInputLayout
android:id="@+id/input_layout_title"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_marginTop="10dp">
<EditText
android:id="@+id/edt_title"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:hint="Title(maximum 100 characters)"
android:inputType="textNoSuggestions|textVisiblePassword"
android:maxLength="100"
android:singleLine="true" />
</android.support.design.widget.TextInputLayout>
<EditText
android:id="@+id/edt_desc"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_marginTop="10dp"
android:focusable="false"
android:hint="Description(maximum 5000 characters)"
android:singleLine="true" />
</LinearLayout>
</android.support.v7.widget.CardView>
<CheckBox
android:id="@+id/cb_stockimage"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginTop="10dp"
android:text="Add this image you own to stock image"
android:visibility="gone" />
<Button
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:text="dummy"
android:visibility="invisible" />
<Button
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:text="dummy"
android:visibility="invisible" />
</LinearLayout>
</LinearLayout>
</ScrollView>
</LinearLayout>
<RelativeLayout
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_gravity="bottom|center_horizontal">
<Button
android:id="@+id/btn_next_sa2"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_alignParentBottom="true"
android:layout_alignParentLeft="true"
android:layout_alignParentStart="true"
android:background="@drawable/button_corners"
android:text="Next"
android:textColor="@color/textColorPrimary"
android:textSize="@dimen/textSize"
android:textStyle="bold" />
</RelativeLayout>
</FrameLayout>
它工作正常。这是我得到的结果
如您所见，计数显示在 EditText 下方。但是当软键盘弹出时，用户将无法看到计数。所以我希望它出现在 EditText 上。我知道可以通过在editText上放置另一个textview并使用TextWatcher来完成。但我想使用这种方法，因为它使我的布局文件几乎可读。我真的不明白可跨字符串的概念。所以我不知道在 CharacterCount 类中该做什么。那么我该怎么做才能让计数出现在 EditText(TextInputLayout)....？