一、先来看看效果演示
二、实现原理：
这个其实不难实现，通过一个定时器不断调用TextView的setText就行了，在setText的时候播放打字的音效。
具体代码如下：
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( ); } }
三、使用说明：
1、在xml文件中定义：
<com.uperone.typetext.view.TypeTextView android:id="@+id/typeTxtId" android:layout_width="fill_parent" android:layout_height="wrap_content" android:layout_centerVertical="true" />
2、在代码中实例化：
mTypeTextView = ( TypeTextView )findViewById(R.id.typeTxtId); mTypeTextView.setOnTypeViewListener( new OnTypeViewListener( ) { @Override public void onTypeStart() { print( "onTypeStart" ); } @Override public void onTypeOver() { print( "onTypeOver" ); } });
3、调用start方法：
mTypeTextView.start( TEST_DATA );
四、总结
以上就是Android自定义View实现打字机效果的全部内容，感兴趣的快快自己动手实践起来，希望本文的内容对大家开发Android的时候能有所帮助，如果有疑问可以留言交流。