使用Intent启动Activity传递数据

直接启动

Intent intent=new Intent(MainActivity.this,SecondActivity.this);
StartActivity(intent);

带有返回值的启动

1第一个界面调用statrtActivityForResult(intent,requestCode)

2第二个界面调用getIntent()得到启动的Intent

3关闭第二个界面之前先封装数据

intent.putExtra(“backdata”,edixText.getText().toString());

setCode(RESULT_OK,intent);

关闭界面SecondActivity.this.finish();

//第一个界面接收数据
    @Override
    protected void onActivityResult(int requestCode, int resultCode, Intent data) {
        super.onActivityResult(requestCode, resultCode, data);
       if(resultCode==RESULT_OK){
           text.findViewById(R.id.text);
           String abc=data.getStringExtra("secondbackdata");
           text.setText(abc);
       }

    }
    //第二个界面发送数据
      protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.test1);
        mbutton.findViewById(R.id.button);
        mbutton.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                getIntent();
                intent.putExtra("secondbackdata", editText.getText().toString());
                setResult(RESULT_OK, intent);
                SecondActivity.this.finish();
            }
        });
    }