因为OutOfMemory，我的问题是我的应用程序崩溃了。
首先我的适配器代码：
确实有很多很好的解决方案 public class ImageAdapter extends BaseAdapter {
private Context mContext;
// Keep all Images in array
public Integer[] mThumbIds = {
R.drawable.accidentally_open_internet_explorer,
R.drawable.angry_shaking, R.drawable.are_you_fucking_kidding_me,
R.drawable.angry_with_pc,
R.drawable.sample_7, R.drawable.awkward_moment,
R.drawable.awkward_moment,
R.drawable.beer_guy,
R.drawable.beng,
R.drawable.accidentally_open_internet_explorer, R.drawable.boobs,
R.drawable.big_smile, R.drawable.cereal_guy,
R.drawable.challenge_accepted_drunk, R.drawable.challenge_accepted,
R.drawable.bad_pokerface, R.drawable.challenge_considered,
R.drawable.challenge_denied, R.drawable.challenge_failed,
R.drawable.classic_rage, R.drawable.one_does_not_simply,
R.drawable.computer_stare, R.drawable.computer_slice,
R.drawable.concentrated, R.drawable.concentrate,
R.drawable.concentrated_teeth, R.drawable.cry_pc,
R.drawable.dat_ass, R.drawable.desk_flip,
R.drawable.double_facepalm, R.drawable.duck_yeah,
R.drawable.fap, R.drawable.fap_accepted,
R.drawable.fap_gentleman, R.drawable.feels_good_man,
R.drawable.forever_a_gamer, R.drawable.forever_alone_clean,
R.drawable.forever_alone_sad, R.drawable.forever_alone_together,
R.drawable.fuck_that_bitch_yao_pff, R.drawable.fuck_that_yao_ming,
R.drawable.fuck_yeah, R.drawable.fuck_yeah_close_enough,
R.drawable.gentleman_troll, R.drawable.happy_smoking,
R.drawable.haters_gonna_hate, R.drawable.if_you_know_what_i_mean_mr_bean,
R.drawable.if_you_know_what_i_mean_mr_bean_blank, R.drawable.if_you_know_what_i_mean_mr_bean_blank,
R.drawable.impossibru, R.drawable.indeed,
R.drawable.jesus, R.drawable.keyboard_break,
R.drawable.knowthatfeel, R.drawable.like_a_sir,
R.drawable.long_long_neck_surprise, R.drawable.look_from_bottom,
R.drawable.me_gusta, R.drawable.me_gusta_creepy,
R.drawable.me_gusta_makeup, R.drawable.not_sure_if_gusta,
R.drawable.now_kiss, R.drawable.one_does_not_simply,
R.drawable.sample_1, R.drawable.sample_4,
R.drawable.sample_7, R.drawable.sample_12,
R.drawable.sample_13, R.drawable.today_is_monday,
R.drawable.trees_smile, R.drawable.trees_stoned,
R.drawable.trees_stoned_exhale, R.drawable.trees_stoned_inhale,
R.drawable.wonka, R.drawable.y_u_no,
R.drawable.yea_science, R.drawable.you_are_the_man
};
// Constructor
public ImageAdapter(Context c){
mContext = c;
}
@Override
public int getCount() {
return mThumbIds.length;
}
@Override
public Object getItem(int position) {
return mThumbIds[position];
}
@Override
public long getItemId(int position) {
return 0;
}
@Override
public View getView(int position, View convertView, ViewGroup parent)
.....
然后我尝试了2个解决方案：
First:
public View getView(int position, View convertView, ViewGroup parent) {
//This actually is a bad solution, because every time convertView is reused, you will still initialize new ImageView, which is wrong
//ImageView imageView = new ImageView(this.mContext);
//new BitmapWorkerTask(imageView).execute(Tattoos[position]);
//return imageView;
//Better solution
ImageView imageView = null;
if (convertView == null) {
imageView = new ImageView(this.mContext);
new BitmapWorkerTask(imageView).execute(Tattoos[position]);
//create new ImageView if it is not present and populate it with some image
} else {
imageView = (ImageView) convertView;
//re-use ImageView that already exists in memory
}
return imageView;
}
class BitmapWorkerTask extends AsyncTask<Integer, Void, Bitmap> {
private final WeakReference<ImageView> imageViewReference;
private int data = 0;
public BitmapWorkerTask(ImageView imageView) {
// Use a WeakReference to ensure the ImageView can be garbage collected
imageViewReference = new WeakReference<ImageView>(imageView);
}
// Decode image in background.
@Override
protected Bitmap doInBackground(Integer... params) {
data = params[0];
return decodeSampledBitmapFromResource(ImageAdapter.this.mContext.getResources(), data, 100, 100);
}
// Once complete, see if ImageView is still around and set bitmap.
@Override
protected void onPostExecute(Bitmap bitmap) {
if (imageViewReference != null && bitmap != null) {
final ImageView imageView = imageViewReference.get();
if (imageView != null) {
imageView.setImageBitmap(bitmap);
imageView.setScaleType(ImageView.ScaleType.CENTER_CROP);
imageView.setLayoutParams(new GridView.LayoutParams(100, 70));
}
}
}
}
public 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);
// Calculate inSampleSize
options.inSampleSize = calculateInSampleSize(options, reqWidth, reqHeight);
// Decode bitmap with inSampleSize set
options.inJustDecodeBounds = false;
return BitmapFactory.decodeResource(res, resId, options);
}
public static int calculateInSampleSize(
BitmapFactory.Options options, int reqWidth, int reqHeight) {
// Raw height and width of image
final int height = options.outHeight;
final int width = options.outWidth;
int inSampleSize = 1;
if (height > reqHeight || width > reqWidth) {
// Calculate ratios of height and width to requested height and width
final int heightRatio = Math.round((float) height / (float) reqHeight);
final int widthRatio = Math.round((float) width / (float) reqWidth);
// Choose the smallest ratio as inSampleSize value, this will guarantee
// a final image with both dimensions larger than or equal to the
// requested height and width.
inSampleSize = heightRatio < widthRatio ? heightRatio : widthRatio;
}
return inSampleSize;
}
}
但我的问题是这些照片是彼此叠加的，所以它们彼此叠加为什么???
2解决方案：
@Override
public View getView(int position, View convertView, ViewGroup parent) {
ImageView imageView = new ImageView(mContext);
// TextView txt = new TextView(mContext);
imageView.setImageResource(mThumbIds[position]);
imageView.setScaleType(ImageView.ScaleType.FIT_CENTER);
imageView.setLayoutParams(
new GridView.LayoutParams(RelativeLayout.LayoutParams.WRAP_CONTENT,
RelativeLayout.LayoutParams.WRAP_CONTENT));
Bitmap m_d = BitmapFactory.decodeResource(mContext.getResources(),
mThumbIds[position]);
if (m_d != null)
{
Bitmap resizedBitmap = Bitmap.createScaledBitmap(m_d, 205, 205, true);
imageView.setImageBitmap(resizedBitmap);
};
return imageView;}}
但是为什么会这么迟钝？
谢谢各位帮忙!!!
答案 0 :(得分：0)
每当使用BitmapFactory创建位图时，您必须确保在完成该位图实例时调用.recycle()，否则您将很快耗尽内存。
您的第一个解决方案更接近正确，因为您需要回收这些convertView对象，因此只需确保您的convertView存在，和您已经回收了它可能已经存在的任何位图在创建新的之前坚持下去。
public View getView(int position, View convertView, ViewGroup parent) {
ImageView imageView = null;
if (convertView == null) {
imageView = new ImageView(this.mContext);
} else {
imageView = (ImageView) convertView;
}
// clean up your old bitmap first, if there is one.
if(imageView.getDrawable() instanceof BitmapDrawable){
BitmapDrawable bd = (BitmapDrawable) imageView.getDrawable();
imageView.setDrawable(null);
if(bd.getBitmap() != null){
bd.getBitmap().recycle();
}
bd = null;
}
new BitmapWorkerTask(imageView).execute(Tattoos[position]);
return imageView;
}