（三）页面之间的参数传递

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

finish();

private Button btnStartAty1;
private TextView tvOut;

@Override
protected 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() {
@Override
public 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);
}
});
}

@Override
protected 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() {
@Override
public 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");