Question

我正在通过位置开始结果方法的活动。 place是一个字符串，声明为String place。

Intent intent = new Intent(Intent.ACTION_PICK);
intent.setType("image/*");
intent.putExtra("location",place);
startActivityForResult(intent, RESULT_TRUE);

结果的内部启动活动我尝试使用这两种方法检索其值，但它们都没有工作。

final String place = data.getStringExtra("location");
final String place = data.getExtras().getString("location");

这就是方法的样子

 public  void onActivityResult(int requestCode, int resultCode, Intent data) {
        super.onActivityResult(requestCode, resultCode, data);
        if (requestCode == RESULT_TRUE && resultCode == RESULT_OK) {
            Uri url = data.getData();
            final String place = data.getStringExtra("location");
            StorageReference filepath = mstorage.child("photos").child(url.getLastPathSegment());
            filepath.putFile(url).addOnSuccessListener(new OnSuccessListener<UploadTask.TaskSnapshot>() {
                @O

Answer 1

您可以在global variable中声明一个activity并指定一些您希望传递给onActivityResult()的特定值，如果您在全局范围内声明了这个值，则可以轻松访问该值：

String PLACE;
...
....

        Intent intent = new Intent(Intent.ACTION_PICK);
        intent.setType("image/*");
        PLACE = place;
        //intent.putExtra("location",place);
        startActivityForResult(intent, RESULT_TRUE);

在这种情况下，每次点击按钮时PLACE的值都会有所不同：

public class MyActivity extends AppCompatActivity {

String PLACE;


@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.xx);



    Btn1.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View view) {
            Intent intent = new Intent(Intent.ACTION_PICK);
            intent.setType("image/*");
            PLACE = place;
            //intent.putExtra("location",place);
            startActivityForResult(intent, RESULT_TRUE);
        }
    });

    Btn2.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View view) {
            Intent intent = new Intent(Intent.ACTION_PICK);
            intent.setType("image/*");
            PLACE = place;
            //intent.putExtra("location",place);
            startActivityForResult(intent, RESULT_TRUE);
        }
    });

    Btn3.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View view) {
           Intent intent = new Intent(Intent.ACTION_PICK);
            intent.setType("image/*");
            PLACE = place;
            //intent.putExtra("location",place);
            startActivityForResult(intent, RESULT_TRUE);
        }
    });


}

}

Answer 2

您正试图获取final String place = data.getStringExtra("location");，但数据中不包含名称为＆＃39; location＆＃39;没有人设定它。

仅在您打开图库时才设置它，而不是相反！

Intent intent = new Intent(Intent.ACTION_PICK);
intent.setType("image/*");
intent.putExtra("location",place);
startActivityForResult(intent, RESULT_TRUE);

顺便说一句，您已经拥有位置值是活动本身为什么不使用它！

Answer 3

看来你还没有正确理解这个概念！这可能有助于您理解 startActivityForResult 。在此解释之后，请看下面的答案！

使用startActivityForResult(Intent intent, int requestCode)，您可以开始另一个活动，然后在onActivityResult()方法中从该活动接收结果。{{1来自你开始另一个Activity的地方。

示例

onActivityResult()

public class MainActivity extends Activity { // Use a unique request code for each use case private static final int REQUEST_CODE_EXAMPLE = 0x9988; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); // Create an Intent to start AnotherActivity final Intent intent = new Intent(this, AnotherActivity.class); // Start AnotherActivity with the request code startActivityForResult(intent, REQUEST_CODE_EXAMPLE); } //-------- When a result is returned from another Activity onActivityResult is called.--------- // @Override public void onActivityResult(int requestCode, int resultCode, Intent data) { super.onActivityResult(requestCode, resultCode, data); // First we need to check if the requestCode matches the one we used. if(requestCode == REQUEST_CODE_EXAMPLE) { // The resultCode is set by the AnotherActivity // By convention RESULT_OK means that what ever // AnotherActivity did was successful if(resultCode == Activity.RESULT_OK) { // Get the result from the returned Intent final String result = data.getStringExtra(AnotherActivity.EXTRA_DATA); // Use the data - in this case, display it in a Toast. Toast.makeText(this, "Result: " + result, Toast.LENGTH_LONG).show(); } else { // AnotherActivity was not successful. No data to retrieve. } } } }＆lt; - 这是我们用来向AnotherActivity发送数据的那个

MainActivity

对于你的任务，你不需要以上的方式来获取你的知识，如下所示

public class AnotherActivity extends Activity { // Constant used to identify data sent between Activities. public static final String EXTRA_DATA = "EXTRA_DATA"; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_another); final View button = findViewById(R.id.button); // When this button is clicked we want to return a result button.setOnClickListener(new View.OnClickListener() { @Override public void onClick(View view) { // Create a new Intent as container for the result final Intent data = new Intent(); // Add the required data to be returned to the MainActivity data.putExtra(EXTRA_DATA, "Some interesting data!"); // Set the resultCode to Activity.RESULT_OK to // indicate a success and attach the Intent // which contains our result data setResult(Activity.RESULT_OK, data); // With finish() we close the AnotherActivity to // return to MainActivity finish(); } }); } @Override public void onBackPressed() { // When the user hits the back button set the resultCode // to Activity.RESULT_CANCELED to indicate a failure setResult(Activity.RESULT_CANCELED); super.onBackPressed(); } }

按你想要的按钮！并且它们指向一个名为<Button android:onClick="gatherResults" <--- method name in your class android:id="@+id/button_id_one" android:layout_width="match_parent" android:layout_height="100dp" />的方法，如上所述，然后过滤使用其ID点击的方法

现在在你的班级中写下这个方法，

gatherResults

Answer 4

您将值放在要启动的activity的意图中。因此，您只能在该新活动中获得此值。如果你想在当前活动中使用这个值，那么只需维护一个全局变量，点击你的按钮就可以相应地更新它的值。

Answer 5

试试这个： -

片段： -

View v;
public static String Place;

@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
    v = inflater.inflate(R.layout.yourLayout, container, false);
    return v;
}

@Override
public void onViewCreated(View view, @Nullable Bundle savedInstanceState) {
    super.onViewCreated(view, savedInstanceState);

//Initialize your buttons

 btn1.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v) {
            Place=yourPlace;
            Intent intent = new Intent(Intent.ACTION_PICK);
            intent.setType("image/*");
            startActivityForResult(intent, your_Request_code);
        }
    });

 btn2.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v) {
            Place=yourPlace;
            Intent intent = new Intent(Intent.ACTION_PICK);
            intent.setType("image/*");
            startActivityForResult(intent, your_Request_code);
        }
    });

 btn3.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v) {
            Place=yourPlace;
            Intent intent = new Intent(Intent.ACTION_PICK);
            intent.setType("image/*");
            startActivityForResult(intent, your_Request_code);
        }
    });

}

在活动中： -

String str_place;

@Override
    public void onActivityResult(int requestCode, int resultCode, Intent data) {
        super.onActivityResult(requestCode, resultCode, data);
        if(requestCode == REQUEST_CODE_EXAMPLE) {
            if(resultCode == Activity.RESULT_OK) {          
               str_place=yourFragment.Place;
               //Do your stuff here and use this place object where you want
            } else {

            }
        }
    }

希望这会对你有所帮助:-)： - ）

无法在StartActivityForResult方法中设置字符串值

5 个答案: