我有一些图片文件(png/jpg),当加载到列表视图时,有些需要与另一个透明图片叠加。我使用以下类似的方法来实现:
public Bitmap applyOverlay(Context context, Bitmap sourceImage, int overlayDrawableResourceId){
Bitmap bitmap = null;
try{
int width = sourceImage.getWidth();
int height = sourceImage.getHeight();
Resources r = context.getResources();
Drawable imageAsDrawable = new BitmapDrawable(r, sourceImage);
Drawable[] layers = new Drawable[2];
layers[0] = imageAsDrawable;
layers[1] = new BitmapDrawable(r, BitmapUtils.decodeSampledBitmapFromResource(r, overlayDrawableResourceId, width, height));
LayerDrawable layerDrawable = new LayerDrawable(layers);
bitmap = BitmapUtils.drawableToBitmap(layerDrawable);
}catch (Exception ex){}
return bitmap;
}
BitmapUtils是一个自定义类,实现了位图处理方法。
import android.content.Context;
import android.content.res.Resources;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.graphics.Canvas;
import android.graphics.drawable.BitmapDrawable;
import android.graphics.drawable.Drawable;
import android.graphics.drawable.LayerDrawable;
import android.media.ThumbnailUtils;
import android.widget.ImageView;
import java.io.ByteArrayOutputStream;
import java.io.File;
public class BitmapUtils {
public static Bitmap applyOverlay(Context context, Bitmap sourceImage, int overlayDrawableResourceId){
Bitmap bitmap = null;
try{
int width = sourceImage.getWidth();
int height = sourceImage.getHeight();
Resources r = context.getResources();
Drawable imageAsDrawable = new BitmapDrawable(r, sourceImage);
Drawable[] layers = new Drawable[2];
layers[0] = imageAsDrawable;
layers[1] = new BitmapDrawable(r, BitmapUtils.decodeSampledBitmapFromResource(r, overlayDrawableResourceId, width, height));
LayerDrawable layerDrawable = new LayerDrawable(layers);
bitmap = BitmapUtils.drawableToBitmap(layerDrawable);
}catch (Exception ex){}
return bitmap;
}
public static Bitmap drawableToBitmap(Drawable drawable) {
Bitmap bitmap = null;
if (drawable instanceof BitmapDrawable) {
BitmapDrawable bitmapDrawable = (BitmapDrawable) drawable;
if(bitmapDrawable.getBitmap() != null) {
return bitmapDrawable.getBitmap();
}
}
if(drawable.getIntrinsicWidth() <= 0 || drawable.getIntrinsicHeight() <= 0) {
bitmap = Bitmap.createBitmap(1, 1, Bitmap.Config.ARGB_8888); // Single color bitmap will be created of 1x1 pixel
} else {
bitmap = Bitmap.createBitmap(drawable.getIntrinsicWidth(), drawable.getIntrinsicHeight(), Bitmap.Config.ARGB_8888);
}
Canvas canvas = new Canvas(bitmap);
drawable.setBounds(0, 0, canvas.getWidth(), canvas.getHeight());
drawable.draw(canvas);
return bitmap;
}
static Bitmap decodeSampledBitmapFromResource(Resources res, int resId, int reqWidth, int reqHeight){
// First decode with inJustDecodeBounds=true to check dimensions
final BitmapFactory.Options options = new BitmapFactory.Options();
options.inJustDecodeBounds = true;
BitmapFactory.decodeResource(res, resId, options);
// Compute inSampleSize
options.inSampleSize = computeInSampleSize(options, reqWidth, reqHeight);
// Decode bitmap with inSampleSize set
options.inJustDecodeBounds = false;
return BitmapFactory.decodeResource(res, resId, options);
}
}
使用Universal Image Loader library for Android(简称UIL),通过编写自定义的ImageDecoder并将其应用于ImageLoaderConfiguration可以实现此效果。但问题是,如何使用Glide实现此效果?谢谢。