Question

让我有三个A，B和C类.A传递变量＆＃39; name＆＃39; B使用＆＃39;打算＆＃39;如

Intent intend = new Intent(ViewData.this, MainActivity.class);
intend.putExtra("name1", name);
ViewData.this.startActivity(intend);

B收到姓名＆＃39;如

Intent intent = getIntent();
Uname = intent.getStringExtra("name1");

然后B发送变量＆＃39; name＆＃39;到C并将内容更改为＆＃34; Ramesh＆＃34;。 C发送更新后的变量＆＃39; name＆＃39;回来。

因此B类＆＃39;名称＆＃39;中变量的值必须是＆＃34; Ramesh＆＃34;。但是这个名字＆＃39;显示为null。

为什么变量显示为空？获取变量＆＃39; name＆＃39; as＆＃34; Ramesh＆＃34;，采取什么措施？

Answer 1

首先将数据从A发送到B

 Intent intend = new Intent(ViewData.this, MainActivity.class);
 intend.putExtra("name1", name);
 startActivity(intend);

并像B一样收到B

  Intent intent = getIntent();
  Uname = intent.getStringExtra("name1");

再次传递给C

 Intent intend = new Intent(this,"Your c class name.class");
 intend.putExtra("name1", Uname);
 startActivity(intend);

再次收到C级

 Intent intent = getIntent();
 Uname = intent.getStringExtra("name1");

更改值或您必须做的任何事情。然后在C

执行此操作

  Intent returnIntent = new Intent();
  returnIntent.putExtra("result",result);//your changed value here
  setResult(Activity.RESULT_OK,returnIntent);
  finish();

在班级b上这样做：

  @Override
  protected void onActivityResult(int requestCode, int resultCode, Intent data) {

if (requestCode == 1) {
    if(resultCode == Activity.RESULT_OK){
        String result=data.getStringExtra("result");

        //you will get the changed data here
      }
      if (resultCode == Activity.RESULT_CANCELED) {
          //Write your code if there's no result
     }
  }
  }//onActivityResult

使用三个类之间的Intent传递数据

1 个答案: