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!!

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:

<?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!!

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