简单的为图片添加水印

 1 package com.zzw.addwatermark;
 2 
 3 import android.app.Activity;
 4 import android.graphics.Bitmap;
 5 import android.graphics.Canvas;
 6 import android.graphics.Bitmap.Config;
 7 import android.graphics.Color;
 8 import android.graphics.Paint;
 9 import android.graphics.drawable.BitmapDrawable;
10 import android.graphics.drawable.Drawable;
11 import android.os.Bundle;
12 import android.view.Menu;
13 import android.view.MenuItem;
14 import android.widget.ImageView;
15 
16 
17 public class MainActivity extends Activity {
18 
19     @Override
20     protected void onCreate(Bundle savedInstanceState) {
21         super.onCreate(savedInstanceState);
22         setContentView(R.layout.activity_main);
23         
24         ImageView imageView=(ImageView) findViewById(R.id.imageView);
25         
26         //使用drawable里面的一张图片，我的头像为例
27         Drawable drawable=getResources().getDrawable(R.drawable.test);
28         
29         //把Drawable转换为Bitmap
30         BitmapDrawable bd=(BitmapDrawable) drawable; 
31         Bitmap bm=bd.getBitmap();
32         
33         //为Bitmap添加水印
34         Bitmap bitmap=createWatermark(bm, "www.cnblogs.com/zzw1994");
35         imageView.setImageBitmap(bitmap);
36     }
37     
38     // 为图片target添加水印文字  
39     // Bitmap target：被添加水印的图片  
40     // String mark：水印文章  
41     private Bitmap createWatermark(Bitmap target,String mark){
42         int width=target.getWidth();
43         int height=target.getHeight();
44         
45         Bitmap bitmap=Bitmap.createBitmap(width, height, Config.ARGB_8888);
46         Canvas canvas=new Canvas(bitmap);
47         
48         Paint paint=new Paint();
49         
50         //设置水印的颜色
51         paint.setColor(Color.RED);
52         //设置水印字体的大小
53         paint.setTextSize(10);
54         
55         //去锯齿
56         paint.setAntiAlias(true);
57         //获取原图片的内容
58         canvas.drawBitmap(target, 0, 0, paint);
59         // 在最下方的左边位置开始添加水印  
60         canvas.drawText(mark, 0, height, paint);
61         
62         canvas.save(Canvas.ALL_SAVE_FLAG);
63         canvas.restore();
64         
65         
66         return bitmap;
67     }
68     
69 }