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Android, Saving and loading a bitmap in cache from different activities

开发者 https://www.devze.com 2023-04-08 17:04 出处:网络
I have i bitmap that needs to show in a new activity, so i cahe it and in the opened activity i try to load it but i get a nullPointerException. Here i save the image :

I have i bitmap that needs to show in a new activity, so i cahe it and in the opened activity i try to load it but i get a nullPointerException. Here i save the image :

File cacheDir = getBaseContext().getCacheDir();
File f = new File(cacheDir, "pic");

try {
    FileOutputStream out = new FileOutputStream(
            f);
    pic.compress(
            Bitmap.CompressFormat.JPEG,
            100, out);
    out.flush();
    out.close();

} catch (FileNotFoundException e) {
    e.printStackTrace();
} catch (IOException e) {
    e.printStackTrace();
}

Intent intent = new Intent(
        AndroidActivity.this,
        OpenPictureActivity.class);
startActivity(intent);

and then in the new activity i try to open it :

public void onCreate(Bundle icicle) {
    super.onCreate(icicle);

    File cacheDir = getBaseContext().getCacheDir();
    File f = new File(cacheDir, "pic"开发者_开发问答);     
    FileInputStream fis = null;
    try {
        fis = new FileInputStream(f);
    } catch (FileNotFoundException e) {
        // TODO Auto-generated catch block
        e.printStackTrace();
    }
    Bitmap bitmap = BitmapFactory.decodeStream(fis);

    ImageView viewBitmap = (ImageView) findViewById(R.id.icon2);
    viewBitmap.setImageBitmap(bitmap);
    setContentView(R.layout.open_pic_layout);


Just check your code:

ImageView viewBitmap = (ImageView) findViewById(R.id.icon2);
viewBitmap.setImageBitmap(bitmap);
setContentView(R.layout.open_pic_layout);

You have written findViewById() before setting Content View. Its wrong.

public void onCreate(Bundle icicle) {
    super.onCreate(icicle);
    setContentView(R.layout.open_pic_layout);

  // do your operations here
  }
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