Android编程实现文字倒影效果的方法

本文实例讲述了android编程实现文字倒影效果的方法。分享给大家供大家参考，具体如下：

我们所有的view都继承自view类，view类里有个方法叫ondraw(). 即，我们看到的界面都是画出来的，所以我们可以重写ondraw()方法。

既然知道了这点就好办了，还有个难点就是，我们的倒影也是画出来的，那我们从哪去取原始图片呢？熟悉view的童鞋都知道cache这个东西，不错，就是通过cache我们取到了原始图片。

放源码了。，感谢期待。这个只是个demo，并不完善哈，布局什么的还需要调整下，或者我什么时候有空再进行一次封装，就可以直接从布局文件中任意调整了。

布局文件中增加如下代码

<com.tc.reflect.reflecttextview
    android:layout_margintop="20dp"
    android:id="@+id/test_reflect" android:layout_width="fill_parent"
    android:layout_height="50dp" android:textsize="25dp"
    android:textcolor="#ff0000" android:textstyle="bold" android:gravity="top|center_horizontal"
    android:text="不会飞翔的翅膀 xp.c" />
    <com.tc.reflect.reflecttextview
    android:layout_margintop="20dp"
    android:id="@+id/test_reflect" android:layout_width="fill_parent"
    android:layout_height="50dp" android:textsize="25dp"
    android:textcolor="#a0a0a0" android:textstyle="italic" android:gravity="top|center_horizontal"
    android:text="[e-mail]" />

类代码如下：

/*
 * copyright (c) 2011 tc licensed under the apache license, version 2.0 (the "license");
 * you may not use this file except in compliance with the license. you may obtain a copy of the license at
 * http://www.apache.org/licenses/license-2.0 unless required by applicable law or agreed to in writing, software
 * distributed under the license is distributed on an "as is" basis, without warranties or conditions of any kind,
 * either express or implied. see the license for the specific language governing permissions and limitations under the
 * license. this code is base on the android textview and was created by [e-mail]
 *
 * @author tc
 */
package com.tc.reflect;
import android.content.context;
import android.graphics.bitmap;
import android.graphics.canvas;
import android.graphics.lineargradient;
import android.graphics.matrix;
import android.graphics.paint;
import android.graphics.porterduffxfermode;
import android.graphics.porterduff.mode;
import android.graphics.shader.tilemode;
import android.util.attributeset;
import android.widget.textview;
public class reflecttextview extends textview {
  public reflecttextview(context context) {
    super(context);
  }
  public reflecttextview(context context, attributeset attrs, int defstyle) {
    super(context, attrs, defstyle);
  }
  public reflecttextview(context context, attributeset attrs) {
    super(context, attrs);
  }
  @override
  protected void ondraw(canvas canvas) {
    //draw the text from layout()
    super.ondraw(canvas);
    int height = getheight();
    int width = getwidth();
    //make the shadow reverse of y
    matrix matrix = new matrix();
    matrix.prescale(1, -1);
    //make sure you can use the cache
    setdrawingcacheenabled(true);
    //create bitmap from cache,this is the most important of this
    bitmap originalimage = bitmap.createbitmap(getdrawingcache());
    //create the shadow
    bitmap reflectionimage = bitmap.createbitmap(originalimage, 0,
        height / 3, width, height / 3, matrix, false);
    //draw the shadow
    canvas.drawbitmap(reflectionimage, 0, 8 * height / 12, null);
    //process shadow bitmap to make it shadow like
    paint paint = new paint();
    lineargradient shader = new lineargradient(0, 8 * height / 12, 0,
        height, 0x70ffffff, 0x00ffffff, tilemode.clamp);
    paint.setshader(shader);
    paint.setxfermode(new porterduffxfermode(mode.dst_in));
    canvas.drawrect(0, 8 * height / 12, width, height, paint);
  }
}

更多关于android相关内容感兴趣的读者可查看本站专题：《android图形与图像处理技巧总结》、《android开发入门与进阶教程》、《android调试技巧与常见问题解决方法汇总》、《android基本组件用法总结》、《android视图view技巧总结》、《android布局layout技巧总结》及《android控件用法总结》

希望本文所述对大家android程序设计有所帮助。