Android开发之startActivityForResult过时的替代方案

大家好，又见面了，我是你们的朋友全栈君。

如上图所示：

在api29中提示已过时,官方给出的替代方案是上面第二个红框的方法registerForActivityResult

该怎么用呢 ？

先看kotlin版本的写法：

 private val startActivity =
        registerForActivityResult(ActivityResultContracts.StartActivityForResult()) {
            //此处是跳转的result回调方法
            if (it.data != null && it.resultCode == Activity.RESULT_OK) {
                it.data?.getStringExtra(NewWordActivity.EXTRA_REPLY)?.let { reply ->
                    val word = Word(reply)
                    wordViewModel.insert(word)
                }
            } else {
                Toast.makeText(
                    applicationContext,
                    R.string.empty_not_saved,
                    Toast.LENGTH_LONG
                ).show()
            }
        }

 跳转方法

val intent = Intent(this@MainActivity, NewWordActivity::class.java)
//            startActivityForResult(intent, newWordActivityRequestCode)
            startActivity.launch(intent)

再看下Java版本的写法完整版：

/**
 * @author xiayiye5
 * @date 2021/9/23 13:52
 */
public class JumpPage extends AppCompatActivity {
    public void goPage() {
//            startActivityForResult(intent, newWordActivityRequestCode)
        ActivityResultLauncher<Intent> intentActivityResultLauncher = registerForActivityResult(new ActivityResultContracts.StartActivityForResult(), new ActivityResultCallback<ActivityResult>() {
            @Override
            public void onActivityResult(ActivityResult result) {
                //此处是跳转的result回调方法
                if (result.getData() != null && result.getResultCode() == Activity.RESULT_OK) {
                    result.getData().getStringExtra(NewWordActivity.EXTRA_REPLY);
                } else {
                    Toast.makeText(getApplicationContext(), R.string.empty_not_saved, Toast.LENGTH_LONG).show();
                }
            }
        });
        Intent intent = new Intent(JumpPage.this, NewWordActivity.class);
        intentActivityResultLauncher.launch(intent);
    }
}