I ma building a chat application and I am attempting to append an image to an EditText, through use of Picasso to get the image from a URL and the append and ImageGetter to attach the image to the EditText. However, what I have implemented below does not work, as appending messages when using the app displays nothing (but the message does show up in the database).
I have tested without using Picasso, as simply just using the ImageGetter with an image resource within the app works just fine, only it's not from a URL as is required.
What is the proper way to configure the ImageGetter and/or the append method so that this functionality will work with Picasso? Or is there a simpler way?
Append method:
public void appendToMessageHistory(final String username,
final String message) {
if (username != null && message != null) {
Picasso.with(getBaseContext())
.load("http://localhost:3000/uploads/campaign/image/2/2.jpg")
.into(new Target() {
@Override
public void onPrepareLoad(Drawable arg0) {
}
@Override
public void onBitmapLoaded(Bitmap bitmap,
LoadedFrom arg1) {
Drawable drawImage = new BitmapDrawable(
getBaseContext().getResources(), bitmap);
drawImage.setBounds(0, 0,
drawImage.getIntrinsicHeight(),
drawImage.getIntrinsicWidth());
messageHistoryText.append(Html.fromHtml("<b>"
+ username + ":" + "</b>" + "<br>"));
messageHistoryText.append(Html.fromHtml(message
+ "<hr>" + "<br>")
+ System.getProperty("line.separator") + "");
messageHistoryText.append(Html
.fromHtml("<img src = '" + drawImage
+ "'/>",
imageGetter,
null));
}
@Override
public void onBitmapFailed(Drawable arg0) {
}
});
}
}
ImageGetter:
ImageGetter imageGetter = new ImageGetter() {
Drawable imageUsed=null;
@Override
public Drawable getDrawable(String source) {
Picasso.with(getBaseContext())
.load("http://localhost:3000/uploads/campaign/image/2/2.jpg")
.into(new Target() {
@Override
public void onPrepareLoad(Drawable arg0) {
}
@Override
public void onBitmapLoaded(Bitmap bitmap,
LoadedFrom arg1) {
Drawable drawImage = new BitmapDrawable(
getBaseContext().getResources(), bitmap);
drawImage.setBounds(0, 0,
drawImage.getIntrinsicHeight(),
drawImage.getIntrinsicWidth());
imageUsed=drawImage;
}
@Override
public void onBitmapFailed(Drawable arg0) {
}
});
return imageUsed;
}
};
I couldn't get it to work with using Picasso's Target...
My workaround is:
- use an AsyncTask for concurrency
- use Picasso's get() method to load the image synchronously in the AsyncTask's background method
Like this:
public class PicassoImageGetter implements Html.ImageGetter {
final Resources resources;
final Picasso pablo;
final TextView textView;
public PicassoImageGetter(final TextView textView, final Resources resources, final Picasso pablo) {
this.textView = textView;
this.resources = resources;
this.pablo = pablo;
}
@Override public Drawable getDrawable(final String source) {
final BitmapDrawablePlaceHolder result = new BitmapDrawablePlaceHolder();
new AsyncTask<Void, Void, Bitmap>() {
@Override
protected Bitmap doInBackground(final Void... meh) {
try {
return pablo.load(source).get();
} catch (Exception e) {
return null;
}
}
@Override
protected void onPostExecute(final Bitmap bitmap) {
try {
final BitmapDrawable drawable = new BitmapDrawable(resources, bitmap);
drawable.setBounds(0, 0, drawable.getIntrinsicWidth(), drawable.getIntrinsicHeight());
result.setDrawable(drawable);
result.setBounds(0, 0, drawable.getIntrinsicWidth(), drawable.getIntrinsicHeight());
textView.setText(textView.getText()); // invalidate() doesn't work correctly...
} catch (Exception e) {
/* nom nom nom*/
}
}
}.execute((Void) null);
return result;
}
static class BitmapDrawablePlaceHolder extends BitmapDrawable {
protected Drawable drawable;
@Override
public void draw(final Canvas canvas) {
if (drawable != null) {
drawable.draw(canvas);
}
}
public void setDrawable(Drawable drawable) {
this.drawable = drawable;
}
}
Hope this is useful.
Ufkoku
I built upon Thomas' answer. I used the existing Picasso methods to download any images on a different thread and accounted for the placeholder Drawables as well.
public class PicassoImageGetter implements Html.ImageGetter {
private TextView textView = null;
public PicassoImageGetter() {}
public PicassoImageGetter(TextView target) {
textView = target;
}
@Override
public Drawable getDrawable(String source) {
BitmapDrawablePlaceHolder drawable = new BitmapDrawablePlaceHolder();
Context context = FeedSurferApp.getContext();
FeedSurferApp
.getPicasso()
.load(source)
.error(ResourcesCompat.getDrawable(context.getResources(), R.drawable.connection_error, context.getTheme()))
.into(drawable);
return drawable;
}
private class BitmapDrawablePlaceHolder extends BitmapDrawable implements Target {
protected Drawable drawable;
@Override
public void draw(final Canvas canvas) {
if (drawable != null) {
drawable.draw(canvas);
}
}
public void setDrawable(Drawable drawable) {
this.drawable = drawable;
drawable.setBounds(0, 0, drawable.getIntrinsicWidth(), drawable.getIntrinsicHeight());
setBounds(0, 0, drawable.getIntrinsicWidth(), drawable.getIntrinsicHeight());
if (textView != null) {
textView.setText(textView.getText());
}
}
@Override
public void onBitmapLoaded(Bitmap bitmap, Picasso.LoadedFrom from) {
setDrawable(new BitmapDrawable(FeedSurferApp.getContext().getResources(), bitmap));
}
@Override
public void onBitmapFailed(Drawable errorDrawable) {
setDrawable(errorDrawable);
}
@Override
public void onPrepareLoad(Drawable placeHolderDrawable) {}
}
}
I found a way to use ImageGetter with Picasso Target:
public Drawable getDrawable(String source) {
final BitmapDrawablePlaceHolder result = new BitmapDrawablePlaceHolder();
Picasso.with(getContext()).load(source).into(new Target() {
@Override public void onBitmapLoaded(Bitmap bitmap, Picasso.LoadedFrom from) {
final BitmapDrawable drawable = new BitmapDrawable(mContext.getResources(), bitmap);
drawable.setBounds(0, 0, drawable.getIntrinsicWidth(), drawable.getIntrinsicHeight());
result.setDrawable(drawable);
result.setBounds(0, 0, drawable.getIntrinsicWidth(), drawable.getIntrinsicHeight());
content.setText(content.getText());
// cache is now warmed up
}
@Override public void onBitmapFailed(Drawable errorDrawable) { }
@Override public void onPrepareLoad(Drawable placeHolderDrawable) { }
});
return result;
}
This uses the cache and is no longer a synchronous call requiring the AsyncTask.
Credit to: Fetch images with Callback in Picasso?
来源：https://stackoverflow.com/questions/25194549/using-picasso-with-image-getter