如何用java实时更新EditText的TextView？

Question

我有一个应用程序，在这个应用程序中，用户创建的文本会以一种保密的字体语言显示，而英文（非保密）文本会在文本视图中显示。

JAVA

import android.graphics.Typeface;
import android.support.v7.app.ActionBarActivity;
import android.os.Bundle;
import android.view.Menu;
import android.view.MenuItem;
import android.widget.TextView;
import android.widget.EditText;
import android.view.View;
import android.view.View.OnKeyListener;
import android.widget.Button;
import android.view.KeyEvent;

public class MainActivity extends ActionBarActivity {
TextView tv;
EditText et;
private Button convert;

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);
    //Loading our AvianKingdom Codex Font
    Typeface tf = Typeface.createFromAsset(getAssets(), "fonts/WWAvianKingdom-Regular.ttf");
    //Text view label
    tv = (TextView) findViewById(R.id.CustomFontText);
    et = (EditText) findViewById(R.id.CodexMessage);
    //Applying the font
    et.setTypeface(tf);
    //Convert the text
    et.setOnKeyListener(new OnKeyListener() {
        public boolean onKey(View v, int keyCode, KeyEvent event) {
            if (event.getAction() == KeyEvent.ACTION_DOWN) {
                switch (keyCode) {
                    case KeyEvent.KEYCODE_DPAD_CENTER:
                    case KeyEvent.KEYCODE_ENTER:
                        String inputText = et.getText().toString();
                        tv.setText(inputText);
                        return true;
                    default:
                        break;
                }
            }
            return false;
        }
    });
}       

在我的应用程序中，我正试图在用户输入文本时更新文本视图，但到目前为止，我只能在点击按钮时进行更改。

How do I update TextView with EditText in realtime using java inside Android Studio?

我想在点击sendenter按钮之前，在用户输入阶段进行。你认为最好的解决方案是什么？我查了一下TextWatcherKeyListenerKeyClick，但是作为一个Java新手，并不能帮助我决定或完全理解。

Answer 1

搞清楚了！！！我最后研究了很多，发现了一篇非常有用的博文.这里是答案。

  package com.christianlopez.helloworld;
 //De-Raptor-Codex Android Prototype

import android.os.Environment;
import android.support.v7.app.ActionBarActivity;
import android.support.v7.widget.ShareActionProvider;
import android.support.v4.view.MenuItemCompat;
import android.os.Bundle;
import android.view.Menu;
import android.view.MenuItem;
import android.view.KeyEvent;
import android.view.View;
import android.view.View.OnKeyListener;
import android.widget.TextView;
import android.widget.EditText;
import android.text.TextWatcher;
import android.text.Editable;
import android.graphics.Bitmap;
import android.graphics.Bitmap.CompressFormat;
import android.util.Log;
import android.graphics.Typeface;
import android.content.Intent;

import java.io.File;
import java.io.FileOutputStream;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.io.ByteArrayOutputStream;

public class MainActivity extends ActionBarActivity {
TextView CodexTV;
EditText CodexET;

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

    //Loading our AvianKingdom Codex Font
    Typeface tf = Typeface.createFromAsset(getAssets(), "fonts/WWAvianKingdom-Regular.ttf");
    //Text view label
    CodexET = ((EditText) findViewById(R.id.CodexMessage));
    //REAL-TIME Textview change
    CodexET.addTextChangedListener(new TextWatcher() {
        public void afterTextChanged(Editable s) {   //Convert the Text to String
            String inputText = CodexET.getText().toString();
            CodexTV = ((TextView) findViewById(R.id.CustomFontText));
            CodexTV.setText(inputText);
        }
        public void beforeTextChanged(CharSequence s, int start, int count, int after) {
            // TODO Auto-generated method stub
        }
        public void onTextChanged(CharSequence s, int start, int before, int count) {
            // TODO Auto-generated method stub
        }
    });

    //Applying the font
    CodexET.setTypeface(tf);

    //Screenshot our Codex'ed Image
    CodexET.setOnKeyListener(new OnKeyListener()
    {
        public boolean onKey(View v, int keyCode, KeyEvent event)
        {
            if (event.getAction() == KeyEvent.ACTION_DOWN)
            {
                switch (keyCode)
                {
                    case KeyEvent.KEYCODE_DPAD_CENTER:
                        doShare(getDefaultIntent());
                        captureScreen();
                    case KeyEvent.KEYCODE_ENTER:
                        doShare(getDefaultIntent());
                        captureScreen();
                    default:
                        break;
                }
            }
            return false;
        }
    });
}

答案从e.addtextChanged Listener开始。这就设置了应用程序要关注EditText中的任何变化，然后我把这些变化变成一个字符串，并实时转发回Textview。

Answer 2

只是想让你的答案简短一些......就是.addTextChangedListener方法，在这个方法里面，我们在afterTextChanged方法中编码。

CodexET.addTextChangedListener(new TextWatcher() {
        public void afterTextChanged(Editable s) {   //Convert the Text to String
        String inputText = CodexET.getText().toString();
        CodexTV = ((TextView) findViewById(R.id.CustomFontText));
        CodexTV.setText(inputText);
    }
    public void beforeTextChanged(CharSequence s, int start, int count, int after) {
        // Does not do any thing in this case
    }
    public void onTextChanged(CharSequence s, int start, int before, int count) {
        // Does not do any thing in this case
    }
});