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 androidgraphicsBitmap; import androidgraphicsCanvas; import androidgraphicsLinearGradient; import androidgraphicsMatrix; import androidgraphicsPaint; import androidgraphicsPixelFormat; import androidgraphicsPorterDuffXfermode; import androidgraphicsRect; import androidgraphicsRectF; import androidgraphicsBitmapConfig; import androidgraphicsPorterDuffMode; import androidgraphicsShaderTileMode; import androidgraphicsdrawableDrawable; public class ImageUtil { //放大缩小图片 public static Bitmap zoomBitmap(Bitmap bitmap,int w,int h){ int width = bitmapgetWidth(); int height = bitmapgetHeight(); Matrix matrix = new Matrix(); float scaleWidht = ((float)w / width); float scaleHeight = ((float)h / height); matrixpostScale(scaleWidht, scaleHeight); Bitmap newbmp = BitmapcreateBitmap(bitmap, 0, 0, width, height, matrix, true); return newbmp; } //将Drawable转化为Bitmap public static Bitmap drawableToBitmap(Drawable drawable){ int width = drawablegetIntrinsicWidth(); int height = drawablegetIntrinsicHeight(); Bitmap bitmap = BitmapcreateBitmap(width, height, drawablegetOpacity() != PixelFormatOPAQUE ? BitmapConfigARGB_8888 : BitmapConfigRGB_565); Canvas canvas = new Canvas(bitmap); drawablesetBounds(0,0,width,height); drawabledraw(canvas); return bitmap; } //获得圆角图片的方法 public static Bitmap getRoundedCornerBitmap(Bitmap bitmap,float roundPx){ Bitmap output = BitmapcreateBitmap(bitmapgetWidth(), bitmap getHeight(), ConfigARGB_8888); Canvas canvas = new Canvas(output); final int color = 0xff424242; final Paint paint = new Paint(); final Rect rect = new Rect(0, 0, bitmapgetWidth(), bitmapgetHeight()); final RectF rectF = new RectF(rect); paintsetAntiAlias(true); canvasdrawARGB(0, 0, 0, 0); paintsetColor(color); canvasdrawRoundRect(rectF, roundPx, roundPx, paint); paintsetXfermode(new PorterDuffXfermode(ModeSRC_IN)); canvasdrawBitmap(bitmap, rect, rect, paint); return output; } //获得带倒影的图片方法 public static Bitmap createReflectionImageWithOrigin(Bitmap bitmap){ final int reflectionGap = 4; int width = bitmapgetWidth(); int height = bitmapgetHeight(); Matrix matrix = new Matrix(); matrixpreScale(1, -1); Bitmap reflectionImage = BitmapcreateBitmap(bitmap, 0, height/2, width, height/2, matrix, false); Bitmap bitmapWithReflection = BitmapcreateBitmap(width, (height + height/2), ConfigARGB_8888); Canvas canvas = new Canvas(bitmapWithReflection); canvasdrawBitmap(bitmap, 0, 0, null); Paint deafalutPaint = new Paint(); canvasdrawRect(0, height,width,height + reflectionGap, deafalutPaint); canvasdrawBitmap(reflectionImage, 0, height + reflectionGap, null); Paint paint = new Paint(); LinearGradient shader = new LinearGradient(0, bitmapgetHeight(), 0, bitmapWithReflectiongetHeight() + reflectionGap, 0x70ffffff, 0x00ffffff, TileModeCLAMP); paintsetShader(shader); // Set the Transfer mode to be porter duff and destination in paintsetXfermode(new PorterDuffXfermode(ModeDST_IN)); // Draw a rectangle using the paint with our linear gradient canvasdrawRect(0, height, width, bitmapWithReflectiongetHeight() + reflectionGap, paint); return bitmapWithReflection; } }
第三步:修改main.xml布局文件,主要放了两个ImageView控件,代码如下:
第四步:修改主核心程序,ImageDemo.java,代码如下:
package comandroidtutor; import androidappActivity; import androidgraphicsBitmap; import androidgraphicsdrawableDrawable; import androidosBundle; import androidwidgetImageView; public class Imagedemo extends Activity { private ImageView mImageView01,mImageView02; public void onCreate(Bundle savedInstanceState) { superonCreate(savedInstanceState); setContentView(Rlayoutmain); setupViews(); } private void setupViews(){ mImageView01 = (ImageView)findViewById(Ridimage01); mImageView02 = (ImageView)findViewById(Ridimage02); //获取壁纸返回值是Drawable Drawable drawable = getWallpaper(); //将Drawable转化为Bitmap Bitmap bitmap = ImageUtildrawableToBitmap(drawable); //缩放图片 Bitmap zoomBitmap = ImageUtilzoomBitmap(bitmap, 100, 100); //获取圆角图片 Bitmap roundBitmap = ImageUtilgetRoundedCornerBitmap(zoomBitmap, 0f); //获取倒影图片 Bitmap reflectBitmap = ImageUtilcreateReflectionImageWithOrigin(zoomBitmap); //这里可以让Bitmap再转化为Drawable // Drawable roundDrawable = new BitmapDrawable(roundBitmap); // Drawable reflectDrawable = new BitmapDrawable(reflectBitmap); // mImageViewsetBackgroundDrawable(roundDrawable); // mImageViewsetBackgroundDrawable(reflectDrawable); mImageViewsetImageBitmap(roundBitmap); mImageViewsetImageBitmap(reflectBitmap); } }
以上就是本文的全部内容,希望对大家的学习有所帮助,也希望大家多多支持脚本之家。