java - 如何在 RecyclerView 适配器中显示 ImageView onClick 中的 Dialogfragment

Question

我有 ActionBarDialog (DialogFragment)、CarAdapter (RecycleView) 和 SportFragment。我在 SportFragment 中创建方法(infoMethod)来显示 DialogFragment 并正常工作。但如果我想在 CarAdapter 中调用 infoMethod 则不起作用(java.lang.NullPointerException)

SportFragment 中的 infoMethod

public void infoMethod(){
    Bundle args = new Bundle();
    args.putString("title", "Dialog with Action Bar");
    ActionBarDialog actionbarDialog = new ActionBarDialog();
    actionbarDialog.setArguments(args);
    actionbarDialog.show(getActivity().getSupportFragmentManager(),
            "action_bar_frag");
}

我尝试从 CarAdapter 调用 infoMethod

        public MyViewHolder(View view) {
        super(view);

        image= (ImageView) view.findViewById(R.id.imageViewlist);
        image.setOnClickListener(this);

    }
    @Override
    public void onClick(View v) {
        SportFragment infoFrag = new SportFragment();
        if (v.getId() == image.getId()){
            v.startAnimation(AnimationUtils.loadAnimation(v.getContext(), R.anim.imagelist));
            infoFrag.infoMethod(); //call infoMethod not work

            Toast.makeText(v.getContext(), "ITEM PRESSED = " + String.valueOf(getAdapterPosition()), Toast.LENGTH_SHORT).show();
        } else {
            Toast.makeText(v.getContext(), "ROW PRESSED = " + String.valueOf(getAdapterPosition()), Toast.LENGTH_SHORT).show();
        }
    }

日志猫

09-29 13:30:09.292 18661-18661/com.paijostudio.hitungmasa E/AndroidRuntime: FATAL EXCEPTION: main
                                                                             java.lang.NullPointerException
                                                                                 at com.paijostudio.hitungmasa.fragment.SportFragment.infoMethod(SportFragment.java:210)
                                                                                 at com.paijostudio.hitungmasa.adapter.CarAdapter$MyViewHolder.onClick(CarAdapter.java:73)
                                                                                 at android.view.View.performClick(View.java:4204)
                                                                                 at android.view.View$PerformClick.run(View.java:17355)
                                                                                 at android.os.Handler.handleCallback(Handler.java:725)
                                                                                 at android.os.Handler.dispatchMessage(Handler.java:92)
                                                                                 at android.os.Looper.loop(Looper.java:137)
                                                                                 at android.app.ActivityThread.main(ActivityThread.java:5041)
                                                                                 at java.lang.reflect.Method.invokeNative(Native Method)
                                                                                 at java.lang.reflect.Method.invoke(Method.java:511)
                                                                                 at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:793)
                                                                                 at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:560)
                                                                                 at dalvik.system.NativeStart.main(Native Method)

有什么解决方案可以显示DialogFragment吗？谢谢

Answer 1

由于您尝试在应用程序的两个不同区域中创建对话框，我建议将其移至它自己的类中

public class DialogHelper {
    public static void infoMethod(FragmentManager fragmentManager) {
        Bundle args = new Bundle();
        args.putString("title", "Dialog with Action Bar");
        ActionBarDialog actionbarDialog = new ActionBarDialog();
        actionbarDialog.setArguments(args);
        actionbarDialog.show(fragmentManager, "action_bar_frag");
    }
}

然后在 SportFragment 中将您的调用替换为 DialogHelper.infoMethod(getActivity().getSupportFragmentManager());

对于您的 CarAdapter，您需要使用 FragmentManager。

recyclerView.setAdapter(new CarAdapter(getActivity().getSupportFragmentManager()))

...

public class CarAdapter extends RecyclerView.Adapter<MyViewHolder> {
    private FragmentManager fragmentManager;

    public CarAdapter(FragmentManager fragmentManager) {
        this.fragmentManager = fragmentManager;
    }

    public class MyViewHolder {
        ...

        @Override
        public void onClick(View v) {
            if (v.getId() == image.getId()){
                v.startAnimation(AnimationUtils.loadAnimation(v.getContext(), R.anim.imagelist));
                DialogHelper.infoMethod(fragmentManager);

                Toast.makeText(v.getContext(), "ITEM PRESSED = " + String.valueOf(getAdapterPosition()), Toast.LENGTH_SHORT).show();
            } else {
                Toast.makeText(v.getContext(), "ROW PRESSED = " + String.valueOf(getAdapterPosition()), Toast.LENGTH_SHORT).show();
            }
        }
    }
}