Develop Reference

Pass ImageView from one activity to another - Intent - Android

I have 170 images in the drawable folder in my android app. I have one activity displaying all of them. What is want to do is to pass the clicked imageview to another activity (Zoom_activity) where the user can zoom it and play around with it. How do I achieve it?
All the images are 500x500px. So I can't think of decoding them into Bitmaps and passing Btmaps via Intent. Please suggest a better and simple way to do it! I have already had a look at the other answers here on SO but none of them solved my problem.
Here is my code:
Activity_1.java
Intent startzoomactivity = new Intent(Activity_one.this, Zoom_Image.class);
String img_name = name.getText().toString().toLowerCase(); //name is a textview which is in refrence to the imageview.
startzoomactivity.putExtra("getimage", img_name);
startActivity(startzoomactivity);
Zoom_Activity.java
Intent startzoomactivity = getIntent();
String img_res = getIntent().getStringExtra("getimage");
String img_fin = "R.drawable."+img_res;
img.setImageResource(Integer.parseInt(img_fin));
Error: App force closes
Please help me solve this problem!
Thanks!

Integer.parseInt() only works for strings like "1" or "123" that really contain just the string representation of an Integer.
What you need is find a drawable resource by its name.
This can be done using reflection:
String name = "image_0";
final Field field = R.drawable.getField(name);
int id = field.getInt(null);
Drawable drawable = getResources().getDrawable(id);
Or using Resources.getIdentifier():
String name = "image_0";
int id = getResources().getIdentifier(name, "drawable", getPackageName());
Drawable drawable = getResources().getDrawable(id);

What you are trying is wrong. You can not convert "R.drawable.name" with Integer.parseInt. Integer.parseInt is expecting something like "100". You should use
getIdentifier(img_fin, "drawable", getPackageName());
to retrieve the resources id you are looking for

Use getResources().getIdentifier to load image from Drawable in ImageView as:
int img_id = getResources().getIdentifier(img_res, "drawable", getPackageName());
img.setImageResource(img_id);

How to select a drawable image by matching a string value to the image name?

I have an arraylist of strings, I need to randomly select an index and if the string value was
"bear", then set background of button to bear.jpg.
OK, my research shows that resources are accessed by an int id, not their name, I am not sure the best way to achieve what I want to do. Here is my code:
list.add("alligator");
list.add("bear");
list.add("beaver");
list.add("bison");
randomInt = randomGenerator.nextInt(list.size());
b1.setBackgroundResource(R.drawable.list.get(randomInt));
Now of course the last line of the code is wrong, I wrote it to show what I want to achieve. My latest attempt to accomplish this was trying to get the resource id and access the resource this way, but I don't know if this is the way to do this, and if it is I am not using the correct code. I am trying hard to do this by myself but I could use some advice on what to do here. Here is my attempt:
String mDrawableName = "bear";
int resID = getResources().getIdentifier(mDrawableName , "drawable", getPackageName());
String s= Integer.toString(resID);

Use the below code
int resID = getResources().getIdentifier(mDrawableName , "drawable", getPackageName());
b1.setBackgroundResource(resID);

Try this:
list.add("alligator");
list.add("bear");
list.add("beaver");
list.add("bison");
randomInt = randomGenerator.nextInt(list.size());
int resourceId = getResources().getIdentifier(list.get(randomInt), "drawable", getPackageName());
b1.setBackgroundResource(resourceId);

Dynamically handling image resource

I want to change the image resource for bitmap dynamically. But I can't call them with name from the drawable class.
bmp = BitmapFactory.decodeResource(getResources(), R.drawable.getImage(foldername + "/" + imagename));
I need to do something like that but I couldn't find the proper way of doing this.,
EDITED
I think I should be more clear. I store my images under the drawable folder and they are separeted into other folders.
For example;
drawable/imageset1, drawable/imageset2,
and I want to change the Image resource for bitmap depending on user input.
For example:
User selects imageset5 from first spinner, and selects image5.png from another spinner.

I hope this will do what you want
BitmapFactory.decodeResource(getResources(), getResources().getIdentifier(foldername + "/" + imagename , "drawable", getPackageName());
EDITED:
while the above code will work only if you follow android rule which doesn't allow sub directories in drawable folder so the above code will work only when directly accessing images from drawable.
BitmapFactory.decodeResource(getResources(), getResources().getIdentifier( imagename , "drawable", getPackageName());
As these links describe
How to access res/drawable/"folder"
Can the Android drawable directory contain subdirectories?

Make one array of image resources
int []a = int[]
{
R.drawable.one,
R.drawable.two,
R.drawable.three,
R.drawable.four,
};
Then access it in loop
for(int i=0;i<a.length;i++)
{
// a[i]
}

Is it a resource stored in the drawables folder? Then try this method from BitmapFactory
public static Bitmap decodeResource (Resources res, int id)
Where
res = getResources()
and id is the id of the drawable like
R.drawable.picture
Check it out here

you can't do like this. You have to add all images in drawable & use it like
myImage.setBackgroundResource(R.drawable.imageName)
or after downloading the image from web you can apply as
myImage.setBitmap(BitmapFactory.decodeStream(in));
to get the bitmap where in is InputStream

Just try following:
Your image having name "imagename" must be in the folder
String IMAGE_FOLDER_NAME = "YOUR_IMAGE_CONTAINING_FOLDER";
Now, use following code:
String imagename = "YOUR_IMAGE_NAME";
String PACKAGE_NAME=getApplicationContext().getPackageName();
int imgId = getResources().getIdentifier(PACKAGE_NAME+":"+IMAGE_FOLDER_NAME+"/"+imagename , null, null);
System.out.println("IMG ID :: "+imgId); // check this in log
System.out.println("PACKAGE_NAME :: "+PACKAGE_NAME); // check this in log
Bitmap bitmap = BitmapFactory.decodeResource(getResources(),imgId);

Android, reference things in R.drawable. using variables?

say I want to dynamically load an image file in R.drawable.* based on the value of a string
Is there a way to do this? It seems like I need to statically refer to anything in R.

Have you declared the id for the image in XML file? If you did, you can use the following method:
Let's say you have picture.png in your res/drawable folder.
In your activity, you can set your image resource in the main.xml file
<ImageView android:id="#+id/imageId" android:src="#drawable/picture"></ImageView>
In FirstActivity
//to retrieve image using id set in xml.
String imageString = "imageId"
int resID = getResources().getIdentifier(imageString , "id", "package.name");
ImageView image = (ImageView) findViewById(resID);
imageString is the dynamic name. After which you can get the identifier of the dynamic resource.
Another method, you can do this:
//to retrieve image in res/drawable and set image in ImageView
String imageName = "picture"
int resID = getResources().getIdentifier(imageName, "drawable", "package.name");
ImageView image;
image.setImageResource(resID );
You will be able to reference your image resource and set your ImageView to it.

int drawableId = getResources().getIdentifier(drawablename, "drawable", getPackageName());
imageview.setImageResource(drawableId);
Try this. This should work.

Class res = R.string.class;
Field field = res.getField("x" + pos);
headerId = field.getInt(null);
header.setText(headerId);
this works with drawables as well, just edit the string. the header part is not required, it's just an example pulled from something I wrote a while ago.

Android - Open resource from #drawable String

I have:
String uri = "#drawable/myresource.png";
How can I load that in ImageView? this.setImageDrawable?

If you really need to work with a string, try something like this:
private void showImage() {
String uri = "drawable/icon";
// int imageResource = R.drawable.icon;
int imageResource = getResources().getIdentifier(uri, null, getPackageName());
ImageView imageView = (ImageView) findViewById(R.id.myImageView);
Drawable image = getResources().getDrawable(imageResource);
imageView.setImageDrawable(image);
}
Else I would recommend you to work with R.* references like this:
int imageResource = R.drawable.icon;
Drawable image = getResources().getDrawable(imageResource);

First, don't do that, as that #drawable syntax is meaningless in Java code. Use int resourceId=R.drawable.myresource.
If for some reason you do wind up a resource name and need the integer ID, use getIdentifier() on the Resources object.

you can also add your own variable.. in my case scene.name between i followed #pfleidi answers. c stands for context.
String uri = "drawable/" + scene.name;
int imageResource = c.getResources().getIdentifier(uri, null, c.getPackageName());
imageList.setImageResource(imageResource);

Long since overdue, but my favorite is to use the Context:
context.getApplicationContext().getResources().getDrawable(R.drawable.placeholder_image)
where placeholder_image is the id of the resource. In your case, R.drawable.myresource.
Context can be an activity or the application. Pretty much wherever you are has reference to the context, which you can use to get the application's context.

In case anyone else comes across the problem I had, I was loading the image name from JSON and then needed to get the identifier. The second parameter of getIdentifier can be set to "drawable". This is a slight variation on #alia-ramli-ramli answer...
String uri = details.getString("circle").toLowerCase();
int imageResource = context.getResources().getIdentifier(uri, "drawable", context.getPackageName());
Drawable image = context.getResources().getDrawable(imageResource);
viewHolder.unit_circle.setImageDrawable(image);

You can check here
int resID = mContext.getResources().getIdentifier(stringfilename, "drawable", mContext.getPackageName());
iv_imageview.setImageDrawable(ContextCompat.getDrawable(mContext,resID));
you can also retrieve image from mipmap by replacing "drawable" with "mipmap" parameter of getIdentifier() method.

I had the same problem with ... the deprecated etc. etc.
I solved in such a way with minimum API 14 okay.
...
...
ImageView imgPoster = viewCache.getImgPoster(resource);
String uri = "drawable/" + film.getPoster();
int imageResource = context.getResources().getIdentifier(uri, null, context.getPackageName());
Drawable image = ContextCompat.getDrawable(context, imageResource);
imgPoster.setImageDrawable(image);
return convertView;
...
...