Android高手进阶教程(二十二)之Android中几种图像特效处理的集锦汇总!!

2022-06-06 05:45

短信预约 -IT技能 免费直播动态提醒

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(Modeclass="lazy" data-src_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:


<?xml version="0" encoding="utf-8"?> 
<LinearLayout xmlns:android="http://schemasandroidcom/apk/res/android" 
  android:orientation="vertical" 
  android:layout_width="fill_parent" 
  android:layout_height="fill_parent" 
  > 
  <ImageView  
    android:id="@+id/image01"  
    android:layout_width="wrap_content"  
    android:layout_height="wrap_content"  
    android:padding="10px" 
    /> 
  <ImageView 
    android:id="@+id/image02" 
    android:layout_width="wrap_content"  
    android:layout_height="wrap_content"  
    android:padding="10px" 
  /> 
</LinearLayout>

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); 
  } 
}

第五步:运行上述工程,查看效果如下:

OK大功告成了!!