使用 Spinner 打开另一个 class

Question

尝试使用此代码从微调器的下拉列表中打开 class。因此，如果按下帮助，帮助 activity 打开，如果按下导航，导航 class 打开

//declare spinner.
        Spinner dropdown = findViewById(R.id.spinner1);
        String[] items = new String[]{"Help", "Navigation Help"};
        ArrayAdapter<String> adapter = new ArrayAdapter<>(this, android.R.layout.simple_spinner_dropdown_item, items);

        dropdown.setAdapter(adapter);
        
    }

    public void onItemSelected(AdapterView<?> parent, View view,
                               int pos, long id) {
       
        
    }

    public void onNothingSelected(AdapterView<?> parent) {
    
    }
}

Answer 1

由于您使用了 findViewById(...) ，我假设您正在 Activity.

中设置 onItemSelectedListener

Context context = this;
HashMap<String , Class> hashMap = new HashMap<>();
hashMap.put("Naviagtion" , NavigationActivity.class);
hashMap.put("Help" ,HelpActivity.class);

public void onItemSelected(AdapterView<?> parent, View view,
                               int pos, long id) {
       String string = adapter.getItem(pos);
       Intent intent = new Intent(context , hashMap.get(string));
       startActivity(intent);
}