Android EditText的輸入監聽，輸入字元的動態擷取

有時候我們可能會用到時時的監聽EditText輸入字元的時時監聽，監聽字元的個數，做一些Regex的處理等。如下方法可以實現：

我做的是時時的把EditeText輸入的資料同步到TextView上

布局檔案：

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"    xmlns:tools="http://schemas.android.com/tools"    android:layout_width="match_parent"    android:layout_height="match_parent" >    <TextView        android:id="@+id/textview"        android:layout_width="wrap_content"        android:layout_height="wrap_content"        android:layout_centerHorizontal="true"        android:layout_centerVertical="true"        android:padding="@dimen/padding_medium"        tools:context=".Test02Activity" />    <EditText        android:id="@+id/editText1"        android:layout_width="fill_parent"        android:layout_height="wrap_content"        android:layout_alignLeft="@+id/textview"        android:layout_below="@+id/textview"        android:layout_marginTop="31dp"        >        <requestFocus />    </EditText></RelativeLayout>

java代碼：

package com.example.testdemo;import android.os.Bundle;import android.app.Activity;import android.util.Log;import android.view.Menu;import android.view.MenuItem;import android.widget.EditText;import android.widget.TextView;import android.support.v4.app.NavUtils;import android.text.Editable;import android.text.TextWatcher;public class Test02Activity extends Activity {private static final String TAG= "Test";private EditText mEditText;private TextView mTextView;    @Override    public void onCreate(Bundle savedInstanceState) {        super.onCreate(savedInstanceState);        setContentView(R.layout.activity_test02);        mEditText = (EditText) findViewById(R.id.editText1);        mTextView = (TextView) findViewById(R.id.textview);                mEditText.addTextChangedListener(new TextWatcher(){@Overridepublic void afterTextChanged(Editable s) {Log.d(TAG, "afterTextChanged");}@Overridepublic void beforeTextChanged(CharSequence s, int start, int count,int after) {Log.d(TAG, "beforeTextChanged:" + s + "-" + start + "-" + count + "-" + after);}@Overridepublic void onTextChanged(CharSequence s, int start, int before,int count) {Log.d(TAG, "onTextChanged:" + s + "-" + "-" + start + "-" + before + "-" + count);mTextView.setText(s);}                });    }    @Override    public boolean onCreateOptionsMenu(Menu menu) {        getMenuInflater().inflate(R.menu.activity_test02, menu);        return true;    }    }