方法一.利用View.OnKeyListener"同步"显示

    

 

 

EditText  myEdit = (EditText)findViewById(R.id.myEdit);
TextView myText = (TextView)findViewById(R.id.myText);
myEdit.setOnKeyListener(new EditText.OnClickListener(){
public boolean onKey(View v , int keyCode  , KeyEvent event)
{
       myText.setText(myEdit.getText());
       return false;
}
});

方法二.  利用TextWatcher,真正实现同步

import android.app.Activity;
import android.os.Bundle;
import android.text.Editable;
import android.text.TextWatcher;
import android.widget.EditText;
import android.widget.TextView;

public class TextWatcherDemo extends Activity implements TextWatcher{
    /** Called when the activity is first created. */
    private TextView myText;
    private EditText myEdit;
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);

        myText=(TextView)findViewById(R.id.text);
        myEdit=(EditText)findViewById(R.id.edit);

        myEdit.addTextChangedListener(this);
    }
    @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

    }
    @Override
    public void onTextChanged(CharSequence s, int start, int before, int count) {
        // TODO Auto-generated method stub
        myText.setText(myEdit.getText());
    }

}