how to get images dynamically from drawable folder

问题

I have an array like this.

int image[] = {R.drawable.d002_p001,R.drawable.d002_p002,R.drawable.d002_p003,
                   R.drawable.d002_p004,R.drawable.d002_p005,R.drawable.d002_p006};

Right now I have 6 images so I am statically given the name.

If I have some 50 images I cant give each and every file name in array so it needs to be dynamic how can I achieve this.

回答1:

You can use getIdentifier()

for (int j = 1; j < 6; j++) {
   Drawable drawable = getResources().getDrawable(getResources()
                  .getIdentifier("d002_p00"+j, "drawable", getPackageName()));
}

回答2:

You can also use this:

int res = getResources().getIdentifier("<your pakecgename>:drawable/abc", null, null);

回答3:

Something like this could work

Field[] drawables = android.R.drawable.class.getFields();
for (Field f : drawables) {
    try {
        System.out.println("R.drawable." + f.getName());
    } catch (Exception e) {
        e.printStackTrace();
    }
}

回答4:

Use the following line for getting drawable dynamically:

Drawable drawable = this.getResources().getDrawable(R.drawable.yourDrawableID);

This will give you the desired Drawable.

回答5:

public static Drawable getImage(Context context, String name) {
        return context.getResources().getDrawable(context.getResources().getIdentifier(name, "drawable", context.getPackageName()));
}

回答6:

String[] names = new String []{"yout names..."};
    for(String n: names) {
        Utils.GetDrawableByName(n,this);
    }

public class Utils {
public static Drawable GetDrawableByName(String name,Activity context){
    Resources res = context.getResources();
    return res.getDrawable(res.getIdentifier(name,"drawable",context.getPackageName()));
    }
}

回答7:

We can take advantage of Imageview setImageResource as this will efficient than drawable seems, refer below code for the same.

The below code can be used to show the image like gif incase if you have the multiple split image of gif. Just split the gif into individual png from a online tool and put image in the drawable like the below order

image_1.png, image_2.png, etc.

Have the handler to change the image dynamically.

int imagePosition = 1;
    Handler handler = new Handler();
        Runnable runnable = new Runnable() {
            public void run() {
                updateImage();
            }
        };




    public void updateImage() {

                appInstance.runOnUiThread(new Runnable() {
                    @Override
                    public void run() {
                        int resId = getResources().getIdentifier("image_" + imagePosition, "drawable", appInstance.getPackageName());
                        gifImageViewDummy.setImageResource(resId);
                        imagePosition++;
    //Consider you have 30 image for the anim
                        if (imagePosition == 30) {
//this make animation play only once
                            handler.removeCallbacks(runnable);

                        } else {
    //You can define your own time based on the animation
                            handler.postDelayed(runnable, 50);
                        }

//to make animation to continue use below code and remove above if else
// if (imagePosition == 30)
//imagePosition = 1;
// handler.postDelayed(runnable, 50);
// 
                    }
                });
              }

回答8:

package com.example.studio.snakes;

import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.util.Log;
import android.view.View;
import android.widget.ImageView;

import java.util.Random;

public class MainActivity extends AppCompatActivity {

int[] dices = {
        R.drawable.one,
        R.drawable.two,
        R.drawable.three,
        R.drawable.four,
        R.drawable.five,
        R.drawable.six,
};


public void rollTapped(View view){
 Log.i("Button","Button Tapped");
    Random rand = new Random();
    int randomnum = rand.nextInt(6);
    Log.i("Random","Random number is " + randomnum );
    ImageView dice=findViewById(R.id.imageView2);
    dice.setImageResource(dices[randomnum]);


}

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);
}
}

回答9:

use this code to create array and later use that array

int image[] = new int[50];
for (int i = 1 ; i <= 50 ; i++)
{
images[i]  = "R.drawable.d002_p00"+i;
}

main thing you have to take care is the file name must start with "d002_p00" this and after there is digit 1 to 50

来源：https://stackoverflow.com/questions/9156698/how-to-get-images-dynamically-from-drawable-folder