使用android中的putextra和getextra方法从第二个活动转到第一个活动时图像视图的可见性消失了

Question

everyone. I am new in android. I am creating two activities in android ,1st activity has two image view and one button . and 2nd activity has one button. when I go to second activity and then from second activity agian . one image view of 1st activity should visibility gone. how can i do this.

here is my code

Activitymain.xml


  <ImageView
        android:id="@+id/1stimage"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content" />

    <ImageView
        android:id="@+id/2ndimage"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content" />

    <Button
        android:id="@+id/btn1"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="go to second activity" />


   mainactivity.java



     ImageView imageView1, imageView2;
            Button btn;

            @Override
            protected void onCreate(Bundle savedInstanceState) {
                super.onCreate(savedInstanceState);
                setContentView(R.layout.activity_main);
                imageView1 = (ImageView) findViewById(R.id.1stimage);
                imageView2 = (ImageView) findViewById(R.id.2ndimage);
                btn = (Button) findViewById(R.id.btn1);
                btn.setOnClickListener(new OnClickListener() {

                    @Override
                    public void onClick(View arg0) {

                        Intent Firstintent= new Intent(MainActivity.this,SecondActivity.class);
                        startActivity(Firstintent);

                    }
                });

            }
secondactivity.xml

    <Button
            android:id="@+id/btn2"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:text="go to 1st activity" />

secondactivity.java

    Button btn;

        @Override
        protected void onCreate(Bundle savedInstanceState) {
            super.onCreate(savedInstanceState);
            setContentView(R.layout.activity_second);
            btn = (Button) findViewById(R.id.btn2);
            btn.setOnClickListener(new OnClickListener() {

                @Override
                public void onClick(View v) {

                    Intent SecondIntent = new Intent(SecondActivity.this,
                            MainActivity.class);
                    SecondActivity.this.startActivity(SecondIntent);
                    SecondActivity.this.finishActivity();

                }
            });
        }

please help me

Answer 1

Use putextra(tag, some variable to use in mainActivity) and Bundle extras = getIntent().getExtras(); extras.get[type of variable](tag) Bundle extras = getIntent().getExtras(); extras.get[type of variable](tag) to pass a variable (probably a boolean) to tell the onCreate() to show or not show the pic.

EDIT: Here is one way to implement it: in the first activity:

1) Check if there are extras (AKA if second activity was loaded/ there is a true)

2) If (yes) { if (first pic is loaded) { remove first pic } else if (first pick is not but second is loaded) { remove second pic } ... for all the pictures you want to do this to.

Remember you only need to pass true/false from the second activity (and then handle it in the first/one being modified)

Answer 2

Activitymain.xml


  <ImageView
        android:id="@+id/1stimage"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content" />

    <ImageView
        android:id="@+id/2ndimage"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content" />

    <Button
        android:id="@+id/btn1"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="go to second activity" />


   mainactivity.java



     ImageView imageView1, imageView2;
            Button btn;

            @Override
            protected void onCreate(Bundle savedInstanceState) {
                super.onCreate(savedInstanceState);
                setContentView(R.layout.activity_main);
                imageView1 = (ImageView) findViewById(R.id.1stimage);
                imageView2 = (ImageView) findViewById(R.id.2ndimage);
                btn = (Button) findViewById(R.id.btn1);
                btn.setOnClickListener(new OnClickListener() {

                    @Override
                    public void onClick(View arg0) {

                        Intent Firstintent= new Intent(MainActivity.this,SecondActivity.class);
                        startActivity(Firstintent);

                    }
                });
                Bundle extras = getIntent().getExtras();
                if(extras != null){
                   if(extras.getBoolean("isResult", false)){
                      imageView1.setVisability(View.GONE);
                   }
                }

            }
secondactivity.xml

    <Button
            android:id="@+id/btn2"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:text="go to 1st activity" />

secondactivity.java

    Button btn;

        @Override
        protected void onCreate(Bundle savedInstanceState) {
            super.onCreate(savedInstanceState);
            setContentView(R.layout.activity_second);
            btn = (Button) findViewById(R.id.btn2);
            btn.setOnClickListener(new OnClickListener() {

                @Override
                public void onClick(View v) {

                    Intent SecondIntent = new Intent(SecondActivity.this,
                            MainActivity.class);
                    SecondIntent.putExtra("isResult", true);
                    SecondActivity.this.startActivity(SecondIntent);
                    SecondActivity.this.finishActivity();

                }
            });
        }