利用Android中的TextView实现逐字显示动画

public class CTextView extends ViewGroup { } 

public void setText(String text, final Animation animation, int duration) {   int time = 0;   if(text != null && !text.isEmpty()) {     char[] characters = text.toCharArray();     for(char c : characters) {       final TextView t = new TextView(context);       //遍历传入的字符串的每个字符，生成一个TextView，并设置它的动画       t.setText(String.valueOf(c));       t.setTextSize(28);       Handler h = new Handler();       //每隔duration时间，播放下一个TextView的动画       h.postDelayed(new Runnable() {         @Override         public void run() {           addView(t);           t.setAnimation(animation);         }       }, time);        time += duration;      }   } } 

import android.content.Context; import android.os.Handler; import android.util.AttributeSet; import android.view.View; import android.view.ViewGroup; import android.view.animation.Animation; import android.widget.TextView;  /**  * Created by cchen on 2014/9/2.  */ public class CTextView extends ViewGroup {   private Context context;    public CTextView(Context context) {     super(context);     this.context = context;   }    public CTextView(Context context, AttributeSet attrs) {     super(context, attrs);     this.context = context;   }    public CTextView(Context context, AttributeSet attrs, int defStyle) {     super(context, attrs, defStyle);     this.context = context;   }    public void setText(String text, final Animation animation, int duration) {     int time = 0;     if(text != null && !text.isEmpty()) {       char[] characters = text.toCharArray();       for(char c : characters) {         final TextView t = new TextView(context);         //遍历传入的字符串的每个字符，生成一个TextView，并设置它的动画         t.setText(String.valueOf(c));         t.setTextSize(28);         Handler h = new Handler();         //每隔duration时间，播放下一个TextView的动画         h.postDelayed(new Runnable() {           @Override           public void run() {             addView(t);             t.setAnimation(animation);           }         }, time);          time += duration;        }     }   }    @Override   protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {     int measureWidth = measureWidth(widthMeasureSpec);     int measureHeight = measureHeight(heightMeasureSpec);     // 计算自定义的ViewGroup中所有子控件的大小     measureChildren(widthMeasureSpec, heightMeasureSpec);     // 设置自定义的控件MyViewGroup的大小     setMeasuredDimension(measureWidth, measureHeight);   }    @Override   protected void onLayout(boolean changed, int l, int t, int r, int b) {     int childLeft = 0;     // 遍历所有子视图     int childCount = getChildCount();     for (int i = 0; i < childCount; i++) {       View childView = getChildAt(i);        // 获取在onMeasure中计算的视图尺寸       int measureHeight = childView.getMeasuredHeight();       int measuredWidth = childView.getMeasuredWidth();        //将他们横向排列       childView.layout(childLeft, 0, childLeft + measuredWidth, measureHeight);        childLeft += measuredWidth;     }   }    private int measureWidth(int pWidthMeasureSpec) {     int result = 0;     int widthMode = MeasureSpec.getMode(pWidthMeasureSpec);// 得到模式     int widthSize = MeasureSpec.getSize(pWidthMeasureSpec);// 得到尺寸      switch (widthMode) {       /**        * mode共有三种情况，取值分别为MeasureSpec.UNSPECIFIED, MeasureSpec.EXACTLY,        * MeasureSpec.AT_MOST。        *        *        * MeasureSpec.EXACTLY是精确尺寸，        * 当我们将控件的layout_width或layout_height指定为具体数值时如andorid        * :layout_width="50dip"，或者为FILL_PARENT是，都是控件大小已经确定的情况，都是精确尺寸。        *        *        * MeasureSpec.AT_MOST是最大尺寸，        * 当控件的layout_width或layout_height指定为WRAP_CONTENT时        * ，控件大小一般随着控件的子空间或内容进行变化，此时控件尺寸只要不超过父控件允许的最大尺寸即可        * 。因此，此时的mode是AT_MOST，size给出了父控件允许的最大尺寸。        *        *        * MeasureSpec.UNSPECIFIED是未指定尺寸，这种情况不多，一般都是父控件是AdapterView，        * 通过measure方法传入的模式。        */       case MeasureSpec.AT_MOST:       case MeasureSpec.EXACTLY:         result = widthSize;         break;     }     return result;   }    private int measureHeight(int pHeightMeasureSpec) {     int result = 0;      int heightMode = MeasureSpec.getMode(pHeightMeasureSpec);     int heightSize = MeasureSpec.getSize(pHeightMeasureSpec);      switch (heightMode) {       case MeasureSpec.AT_MOST:       case MeasureSpec.EXACTLY:         result = heightSize;         break;     }     return result;   } } 

<LinearLayout 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"   android:orientation="vertical"   tools:context=".NetworkTestActivity">    <com.network.cchen.network.CTextView     android:id="@+id/cTextView"     android:layout_width="match_parent"     android:layout_height="match_parent">   </com.network.cchen.network.CTextView>  </LinearLayout> 

import android.app.Activity; import android.os.Bundle; import android.view.animation.AnimationUtils;  public class TestActivity extends Activity {    @Override   public void onCreate(Bundle savedInstanceState) {     super.onCreate(savedInstanceState);      setContentView(R.layout.activity_network_test);      CTextView cTextView = (CTextView) findViewById(R.id.cTextView);     cTextView.setText("Hello world", AnimationUtils.loadAnimation(this, R.anim.myanim), 300);   } } 

<?xml version="1.0" encoding="utf-8"?> <set xmlns:android="http://schemas.android.com/apk/res/android">   <alpha     android:duration="1000"     android:fromAlpha="0.0"     android:toAlpha="1.0" /> </set>  

<?xml version="1.0" encoding="utf-8"?> <set xmlns:android="http://schemas.android.com/apk/res/android">   <translate     android:duration="1000"     android:fillAfter="true"     android:fromXDelta="50%p"     android:interpolator="@android:anim/anticipate_interpolator"     android:toXDelta="0" /> </set>