129

我的视图布局中有三个EditText小部件。TextWatcher有没有办法对所有三个都使用一个EditTexts？

4

13 回答 13

196

我刚遇到这个问题。我通过创建一个TextWatcher以 View 作为参数的内部类实现来解决它。然后，在方法实现中，只需打开视图即可查看Editable来自哪一个

宣言：

private class GenericTextWatcher implements TextWatcher{

    private View view;
    private GenericTextWatcher(View view) {
        this.view = view;
    }

    public void beforeTextChanged(CharSequence charSequence, int i, int i1, int i2) {}
    public void onTextChanged(CharSequence charSequence, int i, int i1, int i2) {}

    public void afterTextChanged(Editable editable) {
        String text = editable.toString();
        switch(view.getId()){
            case R.id.name:
                model.setName(text);
                break;
            case R.id.email:
                model.setEmail(text);
                break;
            case R.id.phone:
                model.setPhone(text);
                break;
        }
    }
}

用法：

name = (EditText) findViewById(R.id.name);
name.setText(model.getName());
name.addTextChangedListener(new GenericTextWatcher(name));

email = (EditText) findViewById(R.id.email);
email.setText(model.getEmail());
email.addTextChangedListener(new GenericTextWatcher(email));

phone = (EditText) findViewById(R.id.phone);
phone.setText(model.getPhone());
phone.addTextChangedListener(new GenericTextWatcher(phone));
于 2011-05-30T03:25:40.917 回答
47

如果您只想使用 afterTextChanged 比较可编辑项：

@Override
public void afterTextChanged(Editable editable) {
    if (editable == mEditText1.getEditableText()) {
        // DO STH
    } else if (editable == mEditText2.getEditableText()) {
        // DO STH
    }
}
于 2014-06-18T09:33:36.153 回答
12

它将与此代码一起使用

TextWatcher watcher = new TextWatcher() {
  @Override
        public void onTextChanged(CharSequence s, int start, int before, int count) {
            //YOUR CODE
        }

        @Override
        public void beforeTextChanged(CharSequence s, int start, int count, int after) {
            //YOUR CODE
        }

        @Override
        public void afterTextChanged(Editable s) {
          String outputedText = s.toString();

  mOutputText.setText(outputedText);

        }
    };

然后在oncreate中添加这个

  mInputText.addTextChangedListener(watcher);
        e2.addTextChangedListener(watcher);
        e3.addTextChangedListener(watcher);
        e4.addTextChangedListener(watcher);
于 2014-07-22T10:31:30.103 回答
12

MultiTextWatcher 实现

public class MultiTextWatcher {

    private TextWatcherWithInstance callback;

    public MultiTextWatcher setCallback(TextWatcherWithInstance callback) {
        this.callback = callback;
        return this;
    }

    public MultiTextWatcher registerEditText(final EditText editText) {
        editText.addTextChangedListener(new TextWatcher() {
            @Override
            public void beforeTextChanged(CharSequence s, int start, int count, int after) {
                callback.beforeTextChanged(editText, s, start, count, after);
            }

            @Override
            public void onTextChanged(CharSequence s, int start, int before, int count) {
                callback.onTextChanged(editText, s, start, before, count);
            }

            @Override
            public void afterTextChanged(Editable editable) {
                callback.afterTextChanged(editText, editable);
            }
        });

        return this;
    }

    interface TextWatcherWithInstance {
        void beforeTextChanged(EditText editText, CharSequence s, int start, int count, int after);

        void onTextChanged(EditText editText, CharSequence s, int start, int before, int count);

        void afterTextChanged(EditText editText, Editable editable);
    }
}

用法

    new MultiTextWatcher()
            .registerEditText(editText1)
            .registerEditText(editText2)
            .registerEditText(editText3)
            .setCallback(new TextWatcherWithInstance() {
                @Override
                public void beforeTextChanged(EditText editText, CharSequence s, int start, int count, int after) {
                    // TODO: Do some thing with editText
                }

                @Override
                public void onTextChanged(EditText editText, CharSequence s, int start, int before, int count) {
                    // TODO: Do some thing with editText
                }

                @Override
                public void afterTextChanged(EditText editText, Editable editable) {
                    // TODO: Do some thing with editText
                }
            });
于 2015-03-27T18:07:20.440 回答
10

如果您想使用下面提到的onTextChanged比较hashCode()-

@Override
public void onTextChanged(CharSequence charSequence, int i, int i1, int i2) {
    if(charSequence.hashCode() == first_edit_text.getText().hashCode()){
        // do other things 
    }

    if(charSequence.hashCode() == second_edit_text.getText().hashCode()){
       // do other things 
    }

}

或者

如果您想使用下面提到的afterTextChanged比较Editable-

@Override
public void afterTextChanged(Editable editable) {
    if (editable == first_edit_text.getEditableText()) {
        // do other things 
    } else if (editable == second_edit_text.getEditableText()) {
       // do other things 
    }
}
于 2017-11-03T19:50:55.627 回答
7

这是我对 kotlin 的解决方案。您可以简单地使用参照相等 (===) 来检查相同的对象并且它工作得很好。

val mTextWatcher = object : TextWatcher {
        override fun afterTextChanged(et: Editable?) {

            when {
                et === et1.editableText -> {
                    Toast.makeText(this@MainActivity, "EditText 1", Toast.LENGTH_LONG).show()
                }
                et === et2.editableText -> {
                    Toast.makeText(this@MainActivity, "EditText 2", Toast.LENGTH_LONG).show()
                }

            }
        }

        override fun beforeTextChanged(p0: CharSequence?, p1: Int, p2: Int, p3: Int) {
        }
        override fun onTextChanged(p0: CharSequence?, p1: Int, p2: Int, p3: Int) {
        }
    }
    et1.addTextChangedListener(mTextWatcher)
    et2.addTextChangedListener(mTextWatcher)
于 2019-08-24T15:04:04.397 回答
6

让您的类从 Activity 继承并实现 TextWatcher。

然后通过多态的魔力，你只需要订阅事件。

这不会告诉您 TextEdit 发生了什么变化，但是结合使用这个和Sky Kelsey的答案，您可以很好地解决这个问题。

public YourActivity extends Activity implements TextWatcher {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_YourActivity);

        //Subscribe to the events
        EditText txt1 = (EditText) findViewById(R.id.txt1);
        txt1.addTextChangedListener(this);

        EditText txt2 = (EditText) findViewById(R.id.txt2);
        txt2.addTextChangedListener(this);
    }

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

            EditText txt1 = (EditText) findViewById(R.id.txt1);
            EditText txt2 = (EditText) findViewById(R.id.txt2);
            // You probably only want the text value from the EditText. But you get the idea. 
                doStuff(txt1,txt2);
    }

    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        // Inflate the menu; this adds items to the action bar if it is present.
        getMenuInflater().inflate(R.menu.calc, menu);
        return true;
    }

    @Override
    public void afterTextChanged(Editable s) {
        // TODO Auto-generated method stub
    }

    @Override
    public void beforeTextChanged(CharSequence s, int start, int count, int after) {
        // TODO Auto-generated method stub
    }
}
于 2014-02-11T14:13:08.460 回答
6

我知道这是一个老问题，并且有正确的决定。我会自己写，也许它会帮助别人。

模拟我们有 N EditText 的经典示例，如果所有字段都已填充，我们希望显示按钮。这个例子是有道理的，尤其是如果进一步为每个验证器使用验证器。

我就这个问题做了一个例子，但你可以做任何设置

MultiEditText.class

public class MultiEditText extends AppCompatActivity{

EditText ed_1, ed_2, ed_3;
Button btn_ok;

@Override
protected void onCreate(@Nullable Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.multi_edit_text);

    ed_1 = (EditText) findViewById(R.id.ed_1);
    ed_2 = (EditText) findViewById(R.id.ed_2);
    ed_3 = (EditText) findViewById(R.id.ed_3);
    btn_ok = (Button) findViewById(R.id.btn_ok);
    btn_ok.setEnabled(false);

    //if want more here can cycle interface List

     EditText[] edList = {ed_1, ed_2, ed_3};
     CustomTextWatcher textWatcher = new CustomTextWatcher(edList, btn_ok);
     for (EditText editText : edList) editText.addTextChangedListener(textWatcher);

    }
}

现在看起来很简单

CustomTextWatcher.class

public class CustomTextWatcher implements TextWatcher {

View v;
EditText[] edList;

public CustomTextWatcher(EditText[] edList, Button v) {
    this.v = v;
    this.edList = edList;
}

@Override
public void beforeTextChanged(CharSequence s, int start, int count, int after) {}

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

@Override
public void afterTextChanged(Editable s) {
    for (EditText editText : edList) {
        if (editText.getText().toString().trim().length() <= 0) {
            v.setEnabled(false);
            break;
        }
        else v.setEnabled(true);
    }
  }
}

我会添加一个布局，所以你不会浪费时间

multi_edit_text.xml

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:padding="16dp">

<EditText
    android:id="@+id/ed_1"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:layout_alignParentTop="true"
    android:layout_centerHorizontal="true"
    android:layout_marginTop="8dp" />

<EditText
    android:id="@+id/ed_2"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:layout_below="@+id/ed_1"
    android:layout_centerHorizontal="true"
    android:layout_marginTop="8dp" />

<EditText
    android:id="@+id/ed_3"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:layout_below="@+id/ed_2"
    android:layout_centerHorizontal="true"
    android:layout_marginTop="8dp" />

<Button
    android:id="@+id/btn_ok"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:layout_below="@+id/ed_3"
    android:layout_centerHorizontal="true"
    android:layout_marginTop="8dp"
    android:text="OK" />
</RelativeLayout>
于 2016-08-22T14:11:18.893 回答
3 
TextWatcher watcher = new TextWatcher(){

    @Override
    public void beforeTextChanged(CharSequence charSequence, int i, int i1, int i2) {
    }

    @Override
    public void onTextChanged(CharSequence charSequence, int i, int i1, int i2) {
    }

    @Override
    public void afterTextChanged(Editable editable) {
    }
};

然后：

editText1.addTextChangedListener(watcher);
editText2.addTextChangedListener(watcher);
editText3.addTextChangedListener(watcher);
于 2011-04-18T12:23:46.833 回答
3 
public class MainActivity extends AppCompatActivity{
    EditText value1, value2;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        //instantiate EditText controls
        value1 = (EditText)findViewById(R.id.txtValue1);
        value2 = (EditText)findViewById(R.id.txtValue2);

        //set up text changed listener
        value1.addTextChangedListener(new TextChange(value1));               
        value2.addTextChangedListener(new TextChange(value2));                       

        //inner class
        private class TextChange implements TextWatcher {

             View view;
             private TextChange (View v) {
                 view = v;
             }

             @Override
             public void beforeTextChanged(CharSequence s, int start, int count, int after) {

             }


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

                 switch (view.getId()) {
                     case R.id.txtValue1:
                         //insert your TextChangedListener codes here
                         break;

                     case R.id.txtValue2:
                         //insert your TextChangedListener codes here
                         break;
                 }
             }   
         }
     }
}
于 2017-04-22T04:54:31.740 回答
1

对于 Kotlin 代码：

set Text Watcher // 在里面创建

 etFirst.addTextChangedListener(generalTextWatcher)
 etFirstSecond.addTextChangedListener(generalTextWatcher)

通用文本观察器的生成函数 // 在创建外部

 private val generalTextWatcher: TextWatcher = object : TextWatcher {
        override fun onTextChanged(
            s: CharSequence, start: Int, before: Int,
            count: Int
        ) {
            when (s.hashCode()) {
                etFirst.text.hashCode() -> { /* take value for first text */ }
                etSecond.text.hashCode() -> { /* take value for second text */ }
            }
        }

        override fun beforeTextChanged(
            s: CharSequence, start: Int, count: Int,
            after: Int
        ) {

        }

        override fun afterTextChanged(s: Editable) {

        }
    }
于 2020-09-16T12:25:21.733 回答
0

我知道这个问题很老，但是我想分享我的一个解决方案（在 Kotlin 中）。我的解决方案是对@Shwarz Andrei 的回答的改进，我的原因是如果你想操纵更多的东西/对象。

而不是同时传递list of EditTexts和a Button作为参数，你只会传递你的list of editText. 然后在您的自定义类中，您将实现一个 lambda，例如：

var hasFilled:((Boolean)->Unit)? = null

然后你将在里面设置或升起它afterTextChanged

override fun afterTextChanged(p0: Editable?) {
       for (edit in _editTextList) {
           if (edit?.text.toString().trim().isEmpty()) {
                 hasFilled?.invoke(false) //<-- here 
               break
           } else {
               hasFilled?.invoke(true) //<--- here 
           }
       }
   }

因此，每次调用您的 lambda 时，某些 EditText 都会发生变化

        val editTexts = listOf(emailEditText,passwordEditText) // your list of editText
        val textWatcher = customTextWatcher(editTexts) // initialize your custom object 
        editTexts.forEach { it -> it?.addTextChangedListener(textWatcher) } // each editText would listen for changes 


        textWatcher.hasFilled = { value ->  // now you have access to your lambda 
            if (value != true)  {
               // change the state of the button to unable 
              // do other things 
            } else {
              // change the state of the button to enable 
              // do other things 
            }
        }
于 2017-08-29T17:03:42.227 回答
0

我是这样做的：

创建一个EditTexts的ArrayList，然后使用for循环为所有EditTexts应用TextWatcher，如果您对所有editTexts都有一个行为，那么只需将其应用到那里，如果您针对某些特定editTexts的特定行为，那么您可以使用if语句来选择并应用到各个editTexts。

这是我的代码：

ArrayList<EditText> editTexts = new ArrayList<>(); // Container list

editText1 = (EditText) findViewById(R.id.editText1);
editText2 = (EditText) findViewById(R.id.editText2);
editText3 = (EditText) findViewById(R.id.editText3);

editTexts.add(editText1); // editTexts[0]
editTexts.add(editText2); // editTexts[1]
editTexts.add(editText3); // editTexts[2]

for (final EditText editText : editTexts) { //need to be final for custom behaviors 
    editText.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) {

        }

        @Override
        public void afterTextChanged(Editable s) {
            //Apply general behavior for all editTexts

            if (editText == editTexts.get(1)) {
                //Apply custom behavior just for this editText                           
            }
        }
    });

}

希望这可以帮助

于 2016-03-29T02:43:17.423 回答