如何在android中的Activity之间传递集合

Question

我要做什么::

• 我正在尝试将集合从一个活动传递到另一个活动并在日志中显示收到的集合
• 我知道这可以使用意图来实现，所以我正在使用它们

我不能做什么::

• 如何在Screen1.java 中接收hashmap 在日志中显示它

---

MainActivity.java

public class MainActivity extends Activity implements OnClickListener{

    HashMap<String, String> objColl;
    Button btn;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        // TODO Auto-generated method stub
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        objColl=new HashMap<String, String>();
        objColl.put("1", "USA");
        objColl.put("2", "Canada");
        objColl.put("3", "Africa");
        objColl.put("4", "England");

        btn=(Button) findViewById(R.id.button1);

        btn.setOnClickListener(this);

    }

    @Override
    public void onClick(View v) {
        // TODO Auto-generated method stub

        switch(v.getId())
        {
        case R.id.button1:
            Intent intent=new Intent(MainActivity.this,Screen1.class);
            intent.putExtra("key1", objColl);
            startActivity(intent);
            break;
        }   
    }
}

Screen1.java

public class Screen1 extends Activity {

    HashMap<String, String> objColl;
    TextView txtVw;
    String res;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        // TODO Auto-generated method stub
        super.onCreate(savedInstanceState);
        txtVw=(TextView) findViewById(R.id.textView1);
    }

    @Override
    protected void onStart() {
        // TODO Auto-generated method stub
        super.onStart();

    }
}

---

日志::

Answer 1

发件人活动：

HashMap<String, String> hashMap= ....
Intent intent = new Intent(SourceActivity.this, DestinationActivity.class);
intent.putExtra("hashMap", hashMap);
startActivity(intent);

接收者活动：

Intent intent = getIntent();    
HashMap<String, String> hashMap = (HashMap<String, String>) intent.getSerializableExtra("hashMap");

Answer 2

获取使用 Bundle 所需的 Extras

Intent mIntent = getIntent();
        if(mIntent != null){
            Bundle mBudle = mIntent.getExtras();
            HashMap<String, String> mMap = (HashMap<String, String>) mBudle.get("key1");
        }

Answer 3

使用 bundle 将集合传递给意图-

Bundle extras = new Bundle();
extras.putSerializable("HashMap",Hash_Map);
intent.putExtras(extras);

&在其他活动中-

Bundle bundle = this.getIntent().getExtras();
 if(bundle!=null){
   Hash_Map= bundle.getSerializable("HashMap");