Android开发ImageUtils工具演示
该工具提供缩放 drawable转换bitmap 转换倒影图 转换成圆角图
1 package com.nailsoul.imagedemo.utils; 2
3 import android.graphics.Bitmap; 4 import android.graphics.Canvas; 5 import android.graphics.LinearGradient; 6 import android.graphics.Matrix; 7 import android.graphics.Paint; 8 import android.graphics.PixelFormat; 9 import android.graphics.PorterDuffXfermode; 10 import android.graphics.Rect; 11 import android.graphics.RectF; 12 import android.graphics.Bitmap.Config; 13 import android.graphics.PorterDuff.Mode; 14 import android.graphics.Shader.TileMode; 15 import android.graphics.drawable.Drawable; 16
17 public class ImageUtil { 18
19 /**
20 * 放大缩小图片 21 * @param bitmap 要放大的图片 22 * @param dstWidth 目标宽 23 * @param dstHeight 目标高 24 * @return
25 */
26 public static Bitmap zoomBitmap(Bitmap bitmap, int dstWidth, int dstHeight) { 27 int width = bitmap.getWidth(); 28 int height = bitmap.getHeight(); 29 Matrix matrix = new Matrix(); 30 float scaleWidht = ((float) dstWidth / width); 31 float scaleHeight = ((float) dstHeight / height); 32 matrix.postScale(scaleWidht, scaleHeight); 33 Bitmap newbmp = Bitmap.createBitmap(bitmap, 0, 0, width, height, 34 matrix, true); 35 return newbmp; 36 } 37
38 /**
39 * 将Drawable转化为Bitmap 40 * @param drawable 41 * @return
42 */
43 public static Bitmap drawableToBitmap(Drawable drawable) { 44 int width = drawable.getIntrinsicWidth(); 45 int height = drawable.getIntrinsicHeight(); 46 Bitmap bitmap = Bitmap.createBitmap(width, height, drawable 47 .getOpacity() != PixelFormat.OPAQUE ? Bitmap.Config.ARGB_8888 48 : Bitmap.Config.RGB_565); 49 Canvas canvas = new Canvas(bitmap); 50 drawable.setBounds(0, 0, width, height); 51 drawable.draw(canvas); 52 return bitmap; 53
54 } 55
56 /**
57 * 获得圆角图片的方法 58 * @param bitmap 59 * @param roundPx 4脚幅度 60 * @return
61 */
62 public static Bitmap getRoundedCornerBitmap(Bitmap bitmap, float roundPx) { 63
64 Bitmap output = Bitmap.createBitmap(bitmap.getWidth(), 65 bitmap.getHeight(), Config.ARGB_8888); 66 Canvas canvas = new Canvas(output); 67
68 final int color = 0xff424242; 69 final Paint paint = new Paint(); 70 final Rect rect = new Rect(0, 0, bitmap.getWidth(), bitmap.getHeight()); 71 final RectF rectF = new RectF(rect); 72
73 paint.setAntiAlias(true); 74 canvas.drawARGB(0, 0, 0, 0); 75 paint.setColor(color); 76 canvas.drawRoundRect(rectF, roundPx, roundPx, paint); 77
78 paint.setXfermode(new PorterDuffXfermode(Mode.SRC_IN)); 79 canvas.drawBitmap(bitmap, rect, rect, paint); 80
81 return output; 82 } 83
84 /**
85 * 获得带倒影的图片方法 86 * @param bitmap 87 * @return
88 */
89 public static Bitmap createReflectionImageWithOrigin(Bitmap bitmap) { 90 final int reflectionGap = 4; 91 int width = bitmap.getWidth(); 92 int height = bitmap.getHeight(); 93
94 Matrix matrix = new Matrix(); 95 matrix.preScale(1, -1); 96
97 Bitmap reflectionImage = Bitmap.createBitmap(bitmap, 0, height / 2, 98 width, height / 2, matrix, false); 99
100 Bitmap bitmapWithReflection = Bitmap.createBitmap(width, 101 (height + height / 2), Config.ARGB_8888); 102
103 Canvas canvas = new Canvas(bitmapWithReflection); 104 canvas.drawBitmap(bitmap, 0, 0, null); 105 Paint deafalutPaint = new Paint(); 106 canvas.drawRect(0, height, width, height + reflectionGap, deafalutPaint); 107
108 canvas.drawBitmap(reflectionImage, 0, height + reflectionGap, null); 109
110 Paint paint = new Paint(); 111 LinearGradient shader = new LinearGradient(0, bitmap.getHeight(), 0, 112 bitmapWithReflection.getHeight() + reflectionGap, 0x70ffffff, 113 0x00ffffff, TileMode.CLAMP); 114 paint.setShader(shader); 115 // Set the Transfer mode to be porter duff and destination in
116 paint.setXfermode(new PorterDuffXfermode(Mode.DST_IN)); 117 // Draw a rectangle using the paint with our linear gradient
118 canvas.drawRect(0, height, width, bitmapWithReflection.getHeight() 119 + reflectionGap, paint); 120
121 return bitmapWithReflection; 122 } 123
124 }
1 package com.nailsoul.imagedemo; 2
3 import java.util.Random; 4
5 import android.app.Activity; 6 import android.graphics.Bitmap; 7 import android.graphics.drawable.Drawable; 8 import android.os.Bundle; 9 import android.view.View; 10 import android.view.Window; 11 import android.view.WindowManager; 12 import android.widget.ImageView; 13 import android.widget.TextView; 14
15 import com.nailsoul.imagedemo.utils.ImageUtil; 16
17 public class ImageDemoActivity extends Activity { 18 private ImageView mIv01, mIv02,mIv03; 19 private TextView mTv01, mtv02,mtv03,mtv00; 20
21 public void onCreate(Bundle savedInstanceState) { 22 super.onCreate(savedInstanceState); 23 int flag=WindowManager.LayoutParams.FLAG_FULLSCREEN; 24 getWindow().setFlags(flag,flag); 25 getWindow().requestFeature(Window.FEATURE_NO_TITLE); 26 setContentView(R.layout.main); 27 setupViews(); 28 } 29
30 private void setupViews() { 31 mIv01 = findView(R.id.image01); 32 mIv02 = findView(R.id.image02); 33 mIv03 = findView(R.id.image03); 34 mtv00=findView(R.id.text00); 35 mTv01=findView(R.id.text01); 36 mtv02=findView(R.id.text02); 37 mtv03=findView(R.id.text03); 38
39 // 获取壁纸返回值是Drawable 40 // Drawable drawable = getWallpaper();
41 Drawable drawable=getResources().getDrawable(R.drawable.a1+new Random().nextInt(15)); 42 // 将Drawable转化为Bitmap
43 Bitmap bitmap = ImageUtil.drawableToBitmap(drawable); 44 // 缩放图片
45 Bitmap zoomBitmap = ImageUtil.zoomBitmap(bitmap, 355, 317); 46 // 获取圆角图片
47 Bitmap roundBitmap = ImageUtil 48 .getRoundedCornerBitmap(bitmap, 10.0f); 49 // 获取倒影图片
50 Bitmap reflectBitmap = ImageUtil 51 .createReflectionImageWithOrigin(zoomBitmap); 52 // 这里可以让Bitmap再转化为Drawable 53 // Drawable roundDrawable = new BitmapDrawable(roundBitmap); 54 // Drawable reflectDrawable = new BitmapDrawable(reflectBitmap); 55 // mImageView01.setBackgroundDrawable(roundDrawable); 56 // mImageView02.setBackgroundDrawable(reflectDrawable);
57
58 mIv01.setImageBitmap(roundBitmap); 59 mIv02.setImageBitmap(reflectBitmap); 60 mIv03.setImageBitmap(zoomBitmap); 61 mtv00.setText("ImageUtils演示"); 62 mTv01.setText("上图为圆角图 width:"+roundBitmap.getWidth()+"height:"+roundBitmap.getHeight()); 63 mtv02.setText("上图为倒影图 width:"+reflectBitmap.getWidth()+"height:"+reflectBitmap.getHeight()); 64 mtv03.setText("上图为缩放图 width:"+zoomBitmap.getWidth()+"height:"+zoomBitmap.getHeight()); 65 } 66
67
68
69 public <T> T findView(int id){ 70 return (T) super.findViewById(id); 71 } 72 }
1 <?xml version="1.0" encoding="utf-8"?> 2 <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" 3 android:layout_width="fill_parent" 4 android:layout_height="fill_parent" 5 android:orientation="vertical" > 6 7 <ScrollView 8 android:layout_width="fill_parent" 9 android:layout_height="fill_parent" 10 android:scrollbars="vertical" > 11 12 <LinearLayout 13 android:layout_width="fill_parent" 14 android:layout_height="fill_parent" 15 android:orientation="vertical" > 16 17 <TextView 18 android:id="@+id/text00" 19 android:layout_width="fill_parent" 20 android:layout_height="wrap_content" 21 android:gravity="center" /> 22 23 <ImageView 24 android:id="@+id/image01" 25 android:layout_width="wrap_content" 26 android:layout_height="wrap_content" 27 android:padding="10px" /> 28 29 <TextView 30 android:id="@+id/text01" 31 android:layout_width="fill_parent" 32 android:layout_height="wrap_content" 33 android:gravity="center" /> 34 35 <ImageView 36 android:id="@+id/image02" 37 android:layout_width="wrap_content" 38 android:layout_height="wrap_content" 39 android:padding="10px" /> 40 41 <TextView 42 android:id="@+id/text02" 43 android:layout_width="fill_parent" 44 android:layout_height="wrap_content" 45 android:gravity="center" /> 46 47 <ImageView 48 android:id="@+id/image03" 49 android:layout_width="wrap_content" 50 android:layout_height="wrap_content" 51 android:padding="10px" /> 52 53 <TextView 54 android:id="@+id/text03" 55 android:layout_width="fill_parent" 56 android:layout_height="wrap_content" 57 android:gravity="center" /> 58 </LinearLayout> 59 </ScrollView> 60 61 </LinearLayout>
来源：http://www.open-open.com/lib/view/open1382151866948.html