Android ImageView设置图像源

Question

I'm trying to set the source of my image, but I get an error.

String test1 = pref.getString("test", "ERROR");
String drawable1 = "R.drawable."+test1;
myImage.setImageResource(drawable1);

I've tried setting int drawable1 = "R.drawable."+test1; , but it still doesn't work. I know it's a mismatch of types, but I can't seem to figure out a way to get it done.

It seems you could break the problem down even further and say how do you make this work?

String drawable1 = "R.drawable.myImage";
myImage.setImageResource(drawable1);

Any ideas?

Answer 1

I've tried setting int drawable1 = "R.drawable."+test1; , but it still doesn't work.

You need to use getIdentifier() to properly build resource ids from Strings:

int drawable1 = getResources().getIdentifier(test1, "drawable", getPackageName());

(There are now two other answer that suggest this same thing... Did I miss something or did they just feel like repeating what's already been stated?)

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As a note, if your Image is large or causes a noticable delay while loading the documentation on setImageResources() has alternate suggestions:

This does Bitmap reading and decoding on the UI thread, which can cause a latency hiccup. If that's a concern, consider using setImageDrawable(android.graphics.drawable.Drawable) or setImageBitmap(android.graphics.Bitmap) and BitmapFactory instead.

Answer 2

Assuming you have a context (use this if the code is within an activity)

int resId = context.getResources().getIdentifier(test1 , "drawable", cw.getPackageName());
myImage.setImageResource(resId);

Answer 3

Use

 int drawable1 =  getResources().getIdentifier(test1, "drawable", getPackageName();

To learn more how to Get Resources by Name see this link