页面一：
private TextView tx1;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
tx1 = (TextView)findViewById(R.id.text2);
}

public void btnText(View view) {
    Intent intent = new Intent(this, Main2Activity.class);


    //传递数据 intent.putExtra();
    startActivityForResult(intent,998);
}

/**
 * 参数说明
 * @param requestCode 998,之前指定码
 * @param resultCode 结果码，结果页面传递过来的数据标记
 * @param data
 */
@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
    super.onActivityResult(requestCode, resultCode, data);
    if (requestCode == 998 && resultCode ==RESULT_OK) {
        //结果码是传递过来的页面，Result.OK ，Result.Cancel是按了onBackPressed
        String result = data.getStringExtra("result");
    tx1.setText(result);
    }
    if (requestCode == 998 && resultCode ==RESULT_CANCELED) {

        tx1.setText("cancel");
    }

}

页面二：
private Intent intent;

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main2);
    intent = new Intent(this, MainActivity.class);//创建意图

}

public void btnCallBack(View view) {

    //设置回传数据的
    intent.putExtra("result","这是结果");

    setResult(RESULT_OK,intent);//设置回传数据
    finish();//关闭页面

}

@Override
public void onBackPressed() {
    super.onBackPressed();
}