Andorid Material Design TextInputLayout和TextInputEditText

TextInputLayout继承自LinearLayout

api:https://developer.android.com/reference/android/support/design/widget/TextInputLayout.html

Layout which wraps an EditText (or descendant) to show a floating label when the hint is hidden due to the user inputting text.

Also supports showing an error via setErrorEnabled(boolean) and setError(CharSequence), and a character counter via setCounterEnabled(boolean).

The TextInputEditText class is provided to be used as a child of this layout. Using TextInputEditText allows TextInputLayout greater control over the visual aspects of any text input.

被设计成用来包裹一个EditText (或者其子类)的布局 ，当它在用户输入、提示文本被隐藏的同时来显示一个浮动的标签 ，同时能够通过 setErrorEnabled(boolean)和setError(CharSequence) 来支持显示一个错误显示，同时可以通过setCounterEnabled(boolean)来显示一个字符计数器，
而TextInputEditText 类是就是被设计成用来作为这个布局包裹子的控件来使用，使用它会让TextInputLayout 更加完善得控制任何输入文本的视觉效果。

An example usage is as so:
下面是简单的事例用法

.support.design.widget.TextInputLayout
         android:layout_width="match_parent"
         android:layout_height="wrap_content">

     .support.design.widget.TextInputEditText
             android:layout_width="match_parent"
             android:layout_height="wrap_content"
             android:hint="@string/form_username"/>

 .support.design.widget.TextInputLayout>

api:https://developer.android.com/reference/android/support/design/widget/TextInputEditText.html

TextInputEditText继承自AppCompatEditText

A special sub-class of EditText designed for use as a child of TextInputLayout.

Using this class allows us to display a hint in the IME when in ‘extract’ mode.

一个特别的EditText 替代类，是被设计成用于TextInputLayout包裹的子控件来使用的，使用它在全屏模式下来显示android:hint提示文字。

所以TextInputLayout最常用的还是包裹EditText 来使用。。。

TextInputLayout常用xml属性

counterEnabled
Whether the layout is laid out as if the character counter will be displayed.
计数器是否可用

counterMaxLength
The max length to display in the character counter.
计数器最大字符长度

errorEnabled
Whether the layout is laid out as if an error will be displayed.
错误信息是否可用

hintAnimationEnabled
Whether to animate hint state changes.
提示信息动画是否可用

hintEnabled
Whether the layout’s floating label functionality is enabled.
提示信息是否可用

hintTextAppearance
提示信息外观

passwordToggleContentDescription
Text to set as the content description for the password input visibility toggle.
设置当前是密码可见状态的描述文本

passwordToggleDrawable
Drawable to use as the password input visibility toggle icon.
密码可见状态切换按钮图标

passwordToggleEnabled
Whether the view will display a toggle when the EditText has a password.
密码可见状态切换按钮是否可用

hint
The hint to display in the floating label.
提示信息

xml

.support.design.widget.TextInputLayout
    android:id="@+id/id_til"
    android:layout_width="200dp"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    app:hintAnimationEnabled="false"
    android:layout_height="wrap_content">
    "@+id/id_et"
        android:layout_width="200dp"
        android:layout_height="wrap_content"
        />
.support.design.widget.TextInputLayout>

code

 final TextInputLayout idtil = (TextInputLayout) findViewById(R.id.id_til);
        idet.addTextChangedListener(new TextWatcher() {
            @Override
            public void beforeTextChanged(CharSequence s, int start, int count, int after) {

            }

            @Override
            public void onTextChanged(CharSequence s, int start, int before, int count) {

                if (s.toString().equals("")){
                    idtil.setError("is empty");
                }else{
                    idtil.setError(null);
                }
            }

            @Override
            public void afterTextChanged(Editable s) {

            }
        });