密码保护应用程序启动

Question

Hey guys i need a way on password protecting my app so when users click the app the password actitivty comes up first and they can only access the app if correct password. Its part of project im doing but im stuck on this bit. PLease guys any hepl would be appreciated.

Answer 1

Assuming you have a button that submits the contexts of TextEdit field:

public class Password extends Activity implements OnClickListener
{
   ... other code

    public void onCreate(Bundle savedInstanceState)
    {
        ...other code
        Button sumbitButton = (Button) findViewById(R.id.submitbutton);
        submitButton.setOnClickListener(this);
    }

    public void onClick(View v)
    { 
        EditText passwordEditText = (EditText) findViewById(R.id.passwordedittext);
        //if people are allowed to set the password on the first run uncomment the following and delete the uncommented section of this function
        //SharedPreferences prefs = this.getApplicationContext().getSharedPreferences("prefs_file",MODE_PRIVATE);
        //String password = prefs.getString("password","");
        //if(password=="")
        //{
        //    SharedPreference.Editor edit = prefs.edit();
        //    edit.putString("password",passwordEditText.getText().ToString());
        //    StartMain();
        //}
        //else
        //{
        //    if(passwordEditText.getText().ToString()==password)
        //    {
        //         StartMain();
        //    }
        //}
        if(passwordEditText.getText().ToString()=="your app password") 
        {
            Intent intent = new Intent(this, your_other_activity.class);
            startActivity(intent);
        }
    }

    public void StartMain()
    {
         Intent intent = new Intent(this, your_other_activity.class);
         startActivity(intent);
    }

This requires in your layout for the password activity you have an edittext called passwordedittext and a button called submitbutton.

And you have your main activity (which needs to be included in your manifest file) which you should replace your_other_activity.class with.

Answer 2

Error in this line:

if(passwordEditText.getText().ToString()=="your app password") 

it should be

if (passwordEditText.getText().ToString().equals("your app password")

When comparing primitive data types (like int, char, boolean) you can use ==, !=, etc. When comparing objects (like String, Car, etc) you need to use the .equals() method.

Answer 3

take the text from your password activity and store it as a SharedPreference. then everytime the user starts the app perform a check against the sharedpreferences you have stored