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>