Transfer data from one Activity to Another Activity Using Intents

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花落未央
花落未央 2020-11-29 06:36

I would like to be able to transfer data from one activity to another activity. How can this be done?

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  • 2020-11-29 07:06

    There are couple of ways by which you can access variables or object in other classes or Activity.

    A. Database

    B. shared preferences.

    C. Object serialization.

    D. A class which can hold common data can be named as Common Utilities it depends on you.

    E. Passing data through Intents and Parcelable Interface.

    It depend upon your project needs.

    A. Database

    SQLite is an Open Source Database which is embedded into Android. SQLite supports standard relational database features like SQL syntax, transactions and prepared statements.

    Tutorials -- http://www.vogella.com/articles/AndroidSQLite/article.html

    B. Shared Preferences

    Suppose you want to store username. So there will be now two thing a Key Username, Value Value.

    How to store

     // Create object of SharedPreferences.
     SharedPreferences sharedPref = PreferenceManager.getDefaultSharedPreferences(this);
     //now get Editor
     SharedPreferences.Editor editor = sharedPref.edit();
     //put your value
     editor.putString("userName", "stackoverlow");
    
     //commits your edits
     editor.commit();
    

    Using putString(),putBoolean(),putInt(),putFloat(),putLong() you can save your desired dtatype.

    How to fetch

    SharedPreferences sharedPref = PreferenceManager.getDefaultSharedPreferences(this);
    String userName = sharedPref.getString("userName", "Not Available");
    

    http://developer.android.com/reference/android/content/SharedPreferences.html

    C. Object Serialization

    Object serlization is used if we want to save an object state to send it over network or you can use it for your purpose also.

    Use java beans and store in it as one of his fields and use getters and setter for that

    JavaBeans are Java classes that have properties. Think of properties as private instance variables. Since they're private, the only way they can be accessed from outside of their class is through methods in the class. The methods that change a property's value are called setter methods, and the methods that retrieve a property's value are called getter methods.

    public class VariableStorage implements Serializable  {
    
        private String inString ;
    
        public String getInString() {
            return inString;
        }
    
        public void setInString(String inString) {
            this.inString = inString;
        }
    
    
    }
    

    Set the variable in you mail method by using

    VariableStorage variableStorage = new VariableStorage();
    variableStorage.setInString(inString);
    

    Then use object Serialzation to serialize this object and in your other class deserialize this object.

    In serialization an object can be represented as a sequence of bytes that includes the object's data as well as information about the object's type and the types of data stored in the object.

    After a serialized object has been written into a file, it can be read from the file and deserialized that is, the type information and bytes that represent the object and its data can be used to recreate the object in memory.

    If you want tutorial for this refer this link

    http://javawithswaranga.blogspot.in/2011/08/serialization-in-java.html

    Get variable in other classes

    D. CommonUtilities

    You can make a class by your self which can contain common data which you frequently need in your project.

    Sample

    public class CommonUtilities {
    
        public static String className = "CommonUtilities";
    
    }
    

    E. Passing Data through Intents

    Please refer this tutorial for this option of passing data.

    http://shri.blog.kraya.co.uk/2010/04/26/android-parcel-data-to-pass-between-activities-using-parcelable-classes/

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  • 2020-11-29 07:08

    Your Purpose

    Suppose You want to Go From Activity A to Activity B.

    So We Use an Intent to switch activity

    the typical code Looks Like this -

    In Activity A [A.class]

    //// Create a New Intent object
    Intent i = new Intent(getApplicationContext(), B.class);
    
    /// add what you want to pass from activity A to Activity B
    i.putExtra("key", "value");
    
    /// start the intent
    startActivity(i);
    

    In Activity B [B.class]

    And to Get the Data From the Child Activity

    Intent i = getIntent();
    
    if (i!=null) {
       String stringData= i.getStringExtra("key");
    }
    
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  • 2020-11-29 07:11

    This works best:

    Through the below code we can send the values between activities

    use the below code in parent activity(PARENT CLASS/ VALUE SENDING CLASS)

    Intent myintent=new Intent(<PARENTCLASSNAMEHERE>.this,<TARGETCLASSNAMEHERE>.class).putExtra("<StringName>", value);
    startActivity(myintent);
    

    use the below code in child activity(TARGET CLASS/ACTIVITY)

    String s= getIntent().getStringExtra(<StringName>);
    

    Please see here that "StringName" is the name that the destination/child activity catches while "value" is the variable name, same as in parent/target/sending class.

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  • 2020-11-29 07:20

    Passing data from one activity to other in android

    Intent intent = new Intent(context, YourActivityClass.class);
    intent.putExtra(KEY, <your value here>);
    
    startActivity(intent);
    

    Retrieving bundle data from android activity

    Intent intent = getIntent();
      if (intent!=null) {
      String stringData= intent.getStringExtra(KEY);
      int numberData = intent.getIntExtra(KEY, defaultValue);
      boolean booleanData = intent.getBooleanExtra(KEY, defaultValue);
      char charData = intent.getCharExtra(KEY, defaultValue);   }
    
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  • 2020-11-29 07:21

    Through the below code we can send the values between activities

    use the below code in parent activity

    Intent myintent=new Intent(Info.this, GraphDiag.class).putExtra("<StringName>", value);
    startActivity(myintent);
    

    use the below code in child activity

    String s= getIntent().getStringExtra(<StringName>);
    
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  • 2020-11-29 07:22

    Hopefully you will find the answer from here Send Data to Another Activity - Simple Android Login

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