Question

我想通过单击按钮将值传递给列表视图。问题是我想通过几个按钮获取不同活动的值来制作一个列表。

例如：在EnglandActivity，如果我点击按钮访问，我想通过＆＃34;英格兰＆＃34;到MainActivity中的 ListView ，在马来西亚，活动通过＆＃34;马来西亚＆＃34;到MainActivity中的ListView。

我不知道该怎么做，你能帮助我吗？

Answer 1

让您的所有活动共享一个对象，将数据放在那里并在必须将数据放入ListView的适配器时阅读它们

Answer 2

    myListView.setOnItemClickListener(new AdapterView.OnItemClickListener() {

        @Override
        public void onItemClick(AdapterView<?> parent, View view, int 
        position, long id) {

            Intent listIntent = new Intent(getApplicationContext(), YourActivity.class); 
            listIntent.putExtra("country", yourList.get(position));
            startActivity(listIntent);
        }
    });

在下一个活动onCreate：

String country;
    Bundle extras = getIntent().getExtras();
    if(extras == null) {
        country= null;
    } else {
        country= extras.getString("country");
    }

Answer 3

首先，您应该在 MainActivity.java 的onCreate()方法上写下这个

 @Override
protected void onCreate(Bundle savedInstanceState){
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);

String data;/*For Storing Country Name*/
ListView listview = (ListView)findViewById(R.id.listView); /*Finding ListView From Layout*/
ArrayList<String> list = new ArrayList<String>(); /*ArrayList To Store All The Data Of ListView*/
ArrayAdapter adapter= new ArrayAdapter<String>(this,R.layout.android.R.layout.simple_list_item_1,list);/*Defining ArrayAdapter For ListView*/
listview.setAdapter(adapter); /*Setting Adapter To ListView*/
Bundle intentExtras = getIntent().getExtras(); /*Getting The Intent Extras Sent By The Activity Which You Had Navigated From*/
if(intentExtras != null) {/*Checking For Null*/
     data= intentExtras.getString("countryName");/*Extracting The Data From The Intent Extras*/
     list.add(0,data);/*You Can Replace 0 With The Position Of Your Wish*/
} else {
    data=null;
      }
}

现在在每个 CountryNameActivity.java

按钮的OnClickListener()方法中写下此内容

 btn.setOnClickListener(new OnClickListener() {/*Setting The Click Listener*/
        @Override
        public void onClick(View v) {
        Intent intent = new Intent(this,MainActivity.this)/*Defining The Intent*/
       intent.putExtra("countryName","CountryName");/*Putting The Data To Pass To The Next Activity*/
       startActivity(intent);/*Starting The Activity*/
        }
    });

通过单击按钮将值传递给ListView

3 个答案: