Activity跳轉&Bundle傳遞資料

Activity的跳轉方式有兩種：

1.startActivity(Intent intent)，直接啟動其他Activity

btnChange = (Button)findViewById(R.id.btnChange);
btnChange.setOnClickListener(new OnClickListener(){

	@Override
	public void onClick(View arg0) {
		// TODO Auto-generated method stub
		Intent mIntent = new Intent();
		mIntent.setClass(MainActivity.this, AnotherActivity.class);
		startActivity(mIntent);
	}});
           

2.startActivityForResult(Intent intent,int requestCode)，以指定的請求碼啟動Activity，并本程式在啟動新Activity後會調用onActivityResult擷取新的Activity傳遞回來的結果

2.1-Bundle:putExtras(Bundle data)/getExtras()、putExtra(String name,Xxx value)/getXxxExtra(String name)

I.MainActivity中的btn調用startActivityForResult：

btnChange = (Button)findViewById(R.id.btnChange);
btnChange.setOnClickListener(new OnClickListener(){

	@Override
	public void onClick(View arg0) {
		// TODO Auto-generated method stub
		Intent mIntent = new Intent(MainActivity.this, AnotherActivity.class);
		startActivityForResult(mIntent,0);
	}});
           

II.MainActivity中重寫onActivityResult監聽傳回的資料

@Override
public void onActivityResult(int requestCode, int resultCode, Intent intent) {
	if(requestCode == 1 && resultCode == 1){
		Bundle data = intent.getExtras();
		//result為AnotherActivity回傳的key為Name的value
		String result = data.getString("Name");
	}
}
           

III.在AnotherActivity中發送資料

btnSend = (Button) findViewById(R.id.btnSend);
btnSend.setOnClickListener(new OnClickListener() {
	@Override
	public void onClick(View v) {
		Intent intent = getIntent();
		intent.putExtra("Name", "John");
		//設定ResultCode
		AnotherActivity.this.setResult(0);
		AnotherActivity.this.finish();
	}
});