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无法从非活动类启动活动

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我试图从我的非活动类开始一个活动，但我得到以下异常：

java.lang.NullPointerException: Attempt to invoke virtual method 'java.lang.String android.content.Context.getPackageName()' on a null object reference

Complete code:

ublic class DecompressFast {
private String _zipFile;
private String _location;
private Context context;

public DecompressFast(String zipFile, String location) {
    _zipFile = zipFile;
    _location = location;
    _dirChecker("");
}

public void unzip() {
    try {
        FileInputStream fin = new FileInputStream(_zipFile);
        ZipInputStream zin = new ZipInputStream(fin);
        ZipEntry ze = null;
        while ((ze = zin.getNextEntry()) != null) {
            Log.v("Decompress", "Unzipping " + ze.getName());
            if (ze.isDirectory()) {
                _dirChecker(ze.getName());
            } else {
                FileOutputStream fout = new FileOutputStream(_location + ze.getName());
                BufferedOutputStream bufout = new BufferedOutputStream(fout);
                byte[] buffer = new byte[1024];
                int read = 0;
                while ((read = zin.read(buffer)) != -1) {
                    bufout.write(buffer, 0, read);
                }
                bufout.close();
                zin.closeEntry();
                fout.close();
            }
        }
        zin.close();
        Log.d("Unzip", "Unzipping complete. path :  " + _location);
        DecompressFast.this.context.startActivity(new Intent(DecompressFast.this.context, AudioList.class));
    } catch (Exception e) {
        Log.e("Decompress", "unzip", e);
        Log.d("Unzip", "Unzipping failed");
    }
}

private void _dirChecker(String dir) {
    File f = new File(_location + dir);

    if (!f.isDirectory()) {
        f.mkdirs();
    }
}

我该如何解决？

android

2 回答

  • 0

    更新构造函数以进行Context初始化 .

    public DecompressFast(String zipFile, String location, Context context) {
    _zipFile = zipFile;
    _location = location;
    this.context = context
    _dirChecker("");
}
    回复于
  • 0

    向构造函数添加上下文

    public DecompressFast(Context ctx,String zipFile, String location) {
     _zipFile = zipFile;
     _location = location;
     _dirChecker("");
     context = ctx;
 }

    我认为更好的方法是使用Activity而不是Context

    回复于

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