Android自定义View实现打字机效果

import java.util.Timer;import java.util.TimerTask;import android.content.Context;import android.media.MediaPlayer;import android.text.TextUtils;import android.util.AttributeSet;import android.widget.TextView;import com.uperone.typetextview.R;/** * 模拟打字机效果 *  * */public class TypeTextView extends TextView { private Context mContext = null; private MediaPlayer mMediaPlayer = null; private String mShowTextString = null; private Timer mTypeTimer = null; private OnTypeViewListener mOnTypeViewListener = null; private static final int TYPE_TIME_DELAY = 80; private int mTypeTimeDelay = TYPE_TIME_DELAY; // 打字间隔 public TypeTextView(Context context, AttributeSet attrs, int defStyle) {  super(context, attrs, defStyle);  initTypeTextView( context ); } public TypeTextView(Context context, AttributeSet attrs) {  super(context, attrs);  initTypeTextView( context ); } public TypeTextView(Context context) {  super(context);  initTypeTextView( context ); } public void setOnTypeViewListener( OnTypeViewListener onTypeViewListener ){  mOnTypeViewListener = onTypeViewListener; } public void start( final String textString ){  start( textString, TYPE_TIME_DELAY ); } public void start( final String textString, final int typeTimeDelay ){  if( TextUtils.isEmpty( textString ) || typeTimeDelay < 0 ){   return;  }  post( new Runnable( ) {   @Override   public void run() {    mShowTextString = textString;    mTypeTimeDelay = typeTimeDelay;    setText( "" );    startTypeTimer( );    if( null != mOnTypeViewListener ){     mOnTypeViewListener.onTypeStart( );    }   }  }); } public void stop( ){  stopTypeTimer( );  stopAudio(); } private void initTypeTextView( Context context ){  mContext = context; } private void startTypeTimer( ){  stopTypeTimer( );  mTypeTimer = new Timer( );  mTypeTimer.schedule( new TypeTimerTask(), mTypeTimeDelay ); } private void stopTypeTimer( ){  if( null != mTypeTimer ){   mTypeTimer.cancel( );   mTypeTimer = null;  } } private void startAudioPlayer() {  stopAudio();  playAudio( R.raw.type_in ); } private void playAudio( int audioResId ){  try{   stopAudio( );   mMediaPlayer = MediaPlayer.create( mContext, audioResId );   mMediaPlayer.start( );  }catch( Exception e ){   e.printStackTrace();  } } private void stopAudio( ){  if( mMediaPlayer != null && mMediaPlayer.isPlaying( ) ){   mMediaPlayer.stop( );   mMediaPlayer.release( );   mMediaPlayer = null;  } } class TypeTimerTask extends TimerTask{  @Override  public void run() {   post(new Runnable( ) {    @Override    public void run() {     if( getText( ).toString( ).length( ) < mShowTextString.length( ) ){      setText( mShowTextString.substring(0, getText( ).toString( ).length( ) + 1 ) );      startAudioPlayer();      startTypeTimer( );     }else{      stopTypeTimer( );      if( null != mOnTypeViewListener ){       mOnTypeViewListener.onTypeOver( );      }     }    }   });  } } public interface OnTypeViewListener{  public void onTypeStart( );  public void onTypeOver( ); }}

 <com.uperone.typetext.view.TypeTextView  android:id="@+id/typeTxtId"  android:layout_width="fill_parent"  android:layout_height="wrap_content"  android:layout_centerVertical="true" />

 mTypeTextView = ( TypeTextView )findViewById(R.id.typeTxtId); mTypeTextView.setOnTypeViewListener( new OnTypeViewListener( ) {  @Override  public void onTypeStart() {   print( "onTypeStart" );  }  @Override  public void onTypeOver() {   print( "onTypeOver" );  } });

mTypeTextView.start( TEST_DATA );