//跳转Aty1
Intent i=new Intent(MainActivity.this,Aty1.class);
//打开
startActivity(i);

finish();

private Button btnStartAty1;private TextView tvOut;@Overrideprotected void onCreate(Bundle savedInstanceState) {super.onCreate(savedInstanceState);setContentView(R.layout.activity_main);btnStartAty1=(Button)findViewById(R.id.btnStartAty1);tvOut=(TextView)findViewById(R.id.tvOut);btnStartAty1.setOnClickListener(new View.OnClickListener() {@Overridepublic void onClick(View view) {Intent i=new Intent(MainActivity.this,Aty1.class);//传递字符串i.putExtra("txt", "adkj");//打开activity并可以接收返回的值startActivityForResult(i,0);}});}@Overrideprotected void onActivityResult(int requestCode, int resultCode, Intent data) {//接收字符串String result=data.getStringExtra("result");tvOut.setText(result);super.onActivityResult(requestCode, resultCode, data);}

private Button btnClose;private TextView tvOut;protected void onCreate(Bundle savedInstanceState){super.onCreate(savedInstanceState);setContentView(R.layout.aty1);btnClose=(Button)findViewById(R.id.btnClose);btnClose.setOnClickListener(new View.OnClickListener() {@Overridepublic void onClick(View view) {Intent i=new Intent();i.putExtra("result","Hello MainActiviy");//发送返回值setResult(0,i);finish();}});tvOut=(TextView)findViewById(R.id.tvOut);tvOut.setText(getIntent().getStringExtra("txt"));}

//跳转Aty1
Intent i=new Intent(MainActivity.this,Aty1.class);
//传递参数
i.putExtra("txt", "adkj");//打开
startActivity(i);

getIntent().getStringExtra("txt")

Intent i=new Intent(MainActivity.this,Aty1.class);Bundle data=new Bundle();
data.putString("txt","Hello Aty1");
i.putExtras(data);startActivity(i);

Bundle data=getIntent().getExtras();
String txt=data.getString("txt");