android意圖傳參返回結果

例如有兩個頁面a，b。a頁面傳參數到b頁面，b頁面將獲得到的參數處理後，再將結果用參數傳回來給頁面a.

1.a頁面的主要MainActivity類的代碼如下：

 

    private Button button;
    private EditText result;
    private final static int REQUESTCODE = 1;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        
        setContentView(R.layout.activity_main);
        button = (Button)this.findViewById(R.id.button1);
        result = (EditText)this.findViewById(R.id.result);
        
        button.setOnClickListener(new View.OnClickListener() {
			
			@Override
			public void onClick(View arg0) {
				// TODO Auto-generated method stub

				Intent intent = new Intent(MainActivity.this,OtherActivity.class);
				intent.putExtra("a", "true");
				
				startActivityForResult(intent,REQUESTCODE);
				
			}
		});
        
    }

@Override protected void onActivityResult(int requestCode,int resultCode,Intent data){ super.onActivityResult(requestCode, resultCode, data); if(resultCode == 2){ if(requestCode == REQUESTCODE){

                        String c= intent.getStringExtra("c");
    			result.setText(c);
    		}
    	}
    }
    

將參數a傳入到b頁面,onActivityResult函數處理將b頁面傳過來的參數c

 

2.OtherActivity.java函數處理a參數後，將c參數傳入回來給a頁面. 在b頁面的onCreate裡面處理

@Override public void onClick(View arg0) { // TODO Auto-generated method stub Intent intent = getIntent(); String a = intent.getStringExtra("a"); String c; if(a=="true"){ c = "It is True"; }else{ c = "It is false"; } Intent newIntent = new Intent(); newIntent.putExtra("c", c); setResult(2,intent); finish(); } });