Android中几种图片特效的处理的实现方法

 Android中几种图片特效的处理

这里有放大缩小图片，获得圆角图片，获得带倒影图片的几种方法及实现代码，

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);
      drawable.setBounds(0,0,width,height);
      drawable.draw(canvas);
      return bitmap; 

    } 

   //获得圆角图片的方法
  public static Bitmap getRoundedCornerBitmap(Bitmap bitmap,float roundPx){ 

    Bitmap output = Bitmap.createBitmap(bitmap.getWidth(), bitmap
        .getHeight(), Config.ARGB_8888);
    Canvas canvas = new Canvas(output); 

    final int color = 0xff424242;
    final Paint paint = new Paint();
    final Rect rect = new Rect(0, 0, bitmap.getWidth(), bitmap.getHeight());
    final RectF rectF = new RectF(rect); 

    paint.setAntiAlias(true);
    canvas.drawARGB(0, 0, 0, 0);
    paint.setColor(color);
    canvas.drawRoundRect(rectF, roundPx, roundPx, paint); 

    paint.setXfermode(new PorterDuffXfermode(Mode.SRC_IN));
    canvas.drawBitmap(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 = bitmap.getWidth();
    int height = bitmap.getHeight(); 

    Matrix matrix = new Matrix();
    matrix.preScale(1, -1); 

    Bitmap reflectionImage = Bitmap.createBitmap(bitmap,
        0, height/2, width, height/2, matrix, false); 

    Bitmap bitmapWithReflection = Bitmap.createBitmap(width, (height + height/2), Config.ARGB_8888); 

    Canvas canvas = new Canvas(bitmapWithReflection);
    canvas.drawBitmap(bitmap, 0, 0, null);
    Paint deafalutPaint = new Paint();
    canvas.drawRect(0, height,width,height + reflectionGap,
        deafalutPaint); 

    canvas.drawBitmap(reflectionImage, 0, height + reflectionGap, null); 

    Paint paint = new Paint();
    LinearGradient shader = new LinearGradient(0,
        bitmap.getHeight(), 0, bitmapWithReflection.getHeight()
        + reflectionGap, 0x70ffffff, 0x00ffffff, TileMode.CLAMP);
    paint.setShader(shader);
    // Set the Transfer mode to be porter duff and destination in
    paint.setXfermode(new PorterDuffXfermode(Mode.DST_IN));
    // Draw a rectangle using the paint with our linear gradient
    canvas.drawRect(0, height, width, bitmapWithReflection.getHeight()
        + reflectionGap, paint); 

    return bitmapWithReflection;
  } 

}

修改main.xml布局文件,主要放了两个ImageView控件,代码如下:

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/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>

修改主核心程序,ImageDemo.Java,代码如下:

package com.android.tutor;
import android.app.Activity;
import android.graphics.Bitmap;
import android.graphics.drawable.Drawable;
import android.os.Bundle;
import android.widget.ImageView;
public class Imagedemo extends Activity {
  private ImageView mImageView01,mImageView02; 

  public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.main);
    setupViews();
  } 

  private void setupViews(){
    mImageView01 = (ImageView)findViewById(R.id.image01);
    mImageView02 = (ImageView)findViewById(R.id.image02); 

    //获取壁纸返回值是Drawable
    Drawable drawable = getWallpaper();
    //将Drawable转化为Bitmap
    Bitmap bitmap = ImageUtil.drawableToBitmap(drawable);
    //缩放图片
    Bitmap zoomBitmap = ImageUtil.zoomBitmap(bitmap, 100, 100);
    //获取圆角图片
    Bitmap roundBitmap = ImageUtil.getRoundedCornerBitmap(zoomBitmap, 10.0f);
    //获取倒影图片
    Bitmap reflectBitmap = ImageUtil.createReflectionImageWithOrigin(zoomBitmap);
    //这里可以让Bitmap再转化为Drawable
//   Drawable roundDrawable = new BitmapDrawable(roundBitmap);
//   Drawable reflectDrawable = new BitmapDrawable(reflectBitmap);
//   mImageView01.setBackgroundDrawable(roundDrawable);
//   mImageView02.setBackgroundDrawable(reflectDrawable); 

    mImageView01.setImageBitmap(roundBitmap);
    mImageView02.setImageBitmap(reflectBitmap);
  } 

}

以上就是Android中几种图片特效的方法整理，如有疑问请留言或者到本站社区交流讨论，感谢阅读，希望能帮助到大家，谢谢大家对本站的支持！