大家好,这一节给大家分享的是Android中几种图像特效处理的小技巧,比如圆角,倒影,还有就是图片缩放,Drawable转化为Bitmap,Bitmap转化为Drawable等等.
废话少说了,直接讲解今天的实例,本例主要是先获取壁纸(getWallpaper()),然后对当前壁纸的一些特效处理.大家按步骤一步一步来:
第一步:新建一个Android工程命名为ImageDemo,工程结构如下:
第二步:新建一个.java文件,命名为ImageUtil.java,在里面定义一些图片处理方法,代码如下:
- package com.android.tutor;
- import android.graphics.Bitmap;
- import android.graphics.Canvas;
- import android.graphics.LinearGradient;
- import android.graphics.Matrix;
- import android.graphics.Paint;
- import android.graphics.PixelFormat;
- import android.graphics.PorterDuffXfermode;
- import android.graphics.Rect;
- import android.graphics.RectF;
- import android.graphics.Bitmap.Config;
- import android.graphics.PorterDuff.Mode;
- import android.graphics.Shader.TileMode;
- import android.graphics.drawable.Drawable;
- public class ImageUtil {
- //放大缩小图片
- public static Bitmap zoomBitmap(Bitmap bitmap,int w,int h){
- int width = bitmap.getWidth();
- int height = bitmap.getHeight();
- Matrix matrix = new Matrix();
- float scaleWidht = ((float)w / width);
- float scaleHeight = ((float)h / height);
- matrix.postScale(scaleWidht, scaleHeight);
- Bitmap newbmp = Bitmap.createBitmap(bitmap, 0, 0, width, height, matrix, true);
- return newbmp;
- }
- //将Drawable转化为Bitmap
- public static Bitmap drawableToBitmap(Drawable drawable){
- int width = drawable.getIntrinsicWidth();
- int height = drawable.getIntrinsicHeight();
- Bitmap bitmap = Bitmap.createBitmap(width, height,
- drawable.getOpacity() != PixelFormat.OPAQUE ? Bitmap.Config.ARGB_8888
- : Bitmap.Config.RGB_565);
- Canvas canvas = new Canvas(bitmap);