Restart Android activity on relaunch of application

Question

I had 3 activities in an android application. The application will exit when I press back button in each activity. Using the following code.

When I press back from the third activity, the application exits fine but when I relaunch the application by clicking the app icon, then the third activity will launch again. But I need to launch my main activity at the time of such "relaunch".

I tried write the code on "onResume" but not working.

@Override
public boolean onKeyDown(int keyCode, KeyEvent event) 
{
    if (keyCode == KeyEvent.KEYCODE_BACK) 
    {
        moveTaskToBack(true);
        return true;
    }
        return super.onKeyDown(keyCode, event);
}

Please help me. Thanks in advance

So that means once the user goes to the next screen , the previous screen is not available for him ? — Anukool, May 10 '13 at 05:36
@SagarMaiyad The default behaviour of the BACK button is to call `finish()` on the current activity. You don't need to override the method and do it yourself. — David Wasser, May 10 '13 at 12:23

score 2 · Answer 1 · answered May 10 '13 at 06:02

You can solve this problem by using following Way In your third Activity class put following Code,

    @Override
public void onBackPressed() {
    // TODO Auto-generated method stub
    super.onBackPressed();
    startActivity(new Intent(getBaseContext(), YourSecondActivity.class));
    finish();
}

Same way You can put in second Activity Class

    @Override
public void onBackPressed() {
    // TODO Auto-generated method stub
    super.onBackPressed();
    startActivity(new Intent(getBaseContext(), YourFirstActivity.class));
    finish();
}

Finally You can put this in your main class

    @Override
public void onBackPressed() {
    // TODO Auto-generated method stub
    super.onBackPressed();
    finish();
}

score 1 · Accepted Answer · answered May 10 '13 at 05:43

Create three activities - A, B and C

In Activity A - when calling startActivity(B), call finish() also. Example -

 public void onButtonClick() // Some method 
 {
    startActivity(intentForB);
    finish();
}

Similarly when going to C from B -

 public void onButtonClick()
 {
    startActivity(intentForC);
    finish();
 }

When the user is on Activity C and when he presses the back button , the application will get closed.(No need to write back button handling explicitly).

Hope this helps.

Linga · Answer 3 · 2013-05-10T05:42:59.570

0

moveTaskToBack() Move the task containing this activity to the back of the activity stack.

Do it in OnBackpressed() and use finish() in all your activities. (Because you said you want to finish all the activities when you have pressed back button)

public void OnBackpressed()
{
 finish();
}

and Simply, in your code do like this:

In activity 1

Intent intent=new Intent(activity1.this,activity2.class);
startActivity(intent);
finish();

In activity 2

Intent intent=new Intent(activity2.this,activity3.class);
startActivity(intent);
finish();

If you used this in your first two activities, Then in third activity no need to handle OnBackpressed(). Because OnBackpressed() is Called when the activity has detected the user's press of the back key. The default implementation simply finishes the current activity, but you can override this to do whatever you want.

edited May 10 '13 at 05:42

answered May 10 '13 at 05:27

Linga

10,379
10
52
104

thanks for your comment... now when I pressed back key, it will go to second view other than exit – ramesh May 10 '13 at 05:36
you can use OnBackpressed() in each activity to handle this. because the default implementation simply finishes the current activity – Linga May 10 '13 at 05:37
use finish() in your all activities when you move to another activity – Linga May 10 '13 at 05:38

Manish Dubey · Answer 4 · 2013-05-10T05:44:58.613

Use this code in your AndroidManifest.xml and android:clearTaskOnLaunch="true" in first launch activity.

 <activity
        android:name="com.example.package.SplashActivity"
        android:label="@string/app_name"
        android:clearTaskOnLaunch="true">
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />
                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
        </activity>

If you want to use Key Event then use this code in your activity :

@Override
    public boolean dispatchKeyEvent(KeyEvent event)
    {
        boolean result = false;
        switch(event.getKeyCode())
        {
            case KeyEvent.KEYCODE_BACK:
                finish(); // or moveTaskToBack(true);
                result = true;
                break;
             default:
                result= super.dispatchKeyEvent(event);
                break;
         }
        return result;
    }

score 0 · Answer 5 · answered May 10 '13 at 05:42

0

If you want to exit in all 3 Activities, then you must close the current Activity using finish() while starting a new Activity.

answered May 10 '13 at 05:42

Bolton

2,226
3
25
29

score 0 · Answer 6 · answered May 10 '13 at 05:47

0

Use this code in your AndroidManifest.xml and android:launchMode="singleTop" in first launch activity.

answered May 10 '13 at 05:47

nilesh patel

834
1
5
10

Restart Android activity on relaunch of application

6 Answers6

Linked