ImageView使用和从内存读取图片显示

import java.io.File;  
  
import android.app.Activity;  
import android.graphics.Bitmap;  
import android.graphics.BitmapFactory;  
import android.os.Bundle;  
import android.view.View;  
import android.widget.Button;  
import android.widget.ImageView;  
import android.widget.TextView;  
  
public class ImageViewActivity extends Activity {  
    private Button myButtonSwitchImg;  
    private ImageView myImageView;  
    private TextView myTextView;  
    private String filename = "/data/data/img.bmp";  
    @Override  
    public void onCreate(Bundle savedInstanceState) {  
        super.onCreate(savedInstanceState);  
        setTitle("ImageView");  
        setContentView(R.layout.imageview);  
        myButtonSwitchImg = (Button) findViewById(R.id.imgButton);  
        myImageView = (ImageView) findViewById(R.id.imageView);  
        myTextView = (TextView) findViewById(R.id.imgText);  
          
        myButtonSwitchImg.setOnClickListener(new Button.OnClickListener() {  
            @Override  
            public void onClick(View v) {  
                File file = new File(filename);  
                if(file.exists()) {  
                    Bitmap bm = BitmapFactory.decodeFile(filename);  
                    myImageView.setImageBitmap(bm);  
                    myTextView.setText(filename);  
                } else {  
                    myTextView.setText("File Not Found!");  
                }  
            }             
        });  
    }  
}