Question

我有3个活动：A，B，C。拥有按钮nextB，这是A中的代码

class A extends AppCompatActivity {
...
  nextB.setOnClickListener(...
    Intent in = new Intent(A.this, B.class);
    startActivityForResult(in, 8);
  );

    @Override
    protected void onActivityResult(int requestCode, int resultCode, @Nullable Intent data) {
        super.onActivityResult(requestCode, resultCode, data);
        if (requestCode == 8 && resultCode == 9) {
            Toast.makeText(this, "ok", Toast.LENGTH_SHORT).show();
        }
    }
}

B有两个按钮：nextC和resetB。这是B中的代码：

class B extends AppCompatActivity {
    ...
      nextC.setOnClickListener(...
        Intent in = new Intent(B.this, C.class);
        startActivityForResult(in, 9);
      );
      resetB.setOnClickListener(...
        Intent in = new Intent(B.this, B.class);
        startActivityForResult(in, 8);
        finish();
      );
      
        @Override
        protected void onActivityResult(int requestCode, int resultCode, @Nullable Intent data) {
            super.onActivityResult(requestCode, resultCode, data);
              if (requestCode == 9 && resultCode == 10) {
                Intent intent = new Intent();
                setResult(9, intent);
                finish();
              }
        }
    }

，在C中，我有按钮finished。这是C中的代码

class C extends AppCompatActivity {
...
  finished.setOnClickListener(...
    Intent intent = new Intent();
    setResult(10, intent);
    finish();
  );   
}

当我从A切换屏幕时，跟随一个nextB-> nextC（单击B）-> finished C移至A并显示祝酒。

但是当我切换屏幕时，请跟随两个nextB-> resetB（单击B）-> nextC（单击B）-> finished C将移至A，但不会显示敬酒。当我在A中调试resultCode时返回0。我尝试在单击finish()时删除resetB，但它返回相同的结果（在A中不显示“确定”对话框。）

在这里发生了什么以及如何在跟随屏幕切换屏幕时显示对话框？非常感谢！

Answer 1

仅在活动A中调用一个结果

class A extends AppCompatActivity {
    ...
      nextB.setOnClickListener(...
        Intent in = new Intent(A.this, B.class);
        startActivityForResult(in, 8);
      );

        @Override
        protected void onActivityResult(int requestCode, int resultCode, @Nullable Intent data) {
            super.onActivityResult(requestCode, resultCode, data);
            if(resultCode == RESULT_OK){
            if (requestCode== 8) {
                Toast.makeText(this, "ok", Toast.LENGTH_SHORT).show();
                   }


        }
    }

在b中使用StartActivityForwardResult到C，并在重置B按钮“赞”按钮中设置结果

 resetB.setOnClickListener(...
        Intent intent = new Intent();
    setResult(RESULT_OK, intent);
    finish();
      );

nextC.setOnClickListener(
        Intent in = new Intent(B.this, C.class);
        intent.setFlags(Intent.FLAG_ACTIVITY_FORWARD_RESULT);
                                    startActivity(intent);

        );

和C活动集结果代码与您在A活动中定义的代码相同

class C extends AppCompatActivity {
...
  finished.setOnClickListener(...
    Intent intent = new Intent();
    setResult(RESULT_OK, intent);
    finish();
  );   
}

为什么resultCode在changeActivityForesult中返回0

1 个答案: