单击按钮加载图像

Question

I have this button which loads an image from an URL. I tried setting the ImageView visibility to Invisible so when I start the app the image doesn't show up until I click the button. But I want to know, is there any other way? Any other way to make it work without setting the ImageView's visibility to invisible .

Here's my code:

public class MainActivity extends Activity {

    String url = "http://test.please.do/app/car.jpg";
    ImageView imageView;
    Button buttonPlay;
    Button buttonFullScreen;
    Button buttonLoad;
    static final int REQUEST_VIDEO_CAPTURE = 1;
    VideoView resultvideo;
    MediaController mediacontroller;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);

        this.requestWindowFeature(Window.FEATURE_NO_TITLE);
        this.getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN,
                WindowManager.LayoutParams.FLAG_FULLSCREEN);

        setContentView(R.layout.activity_main);

        resultvideo = (VideoView)findViewById(R.id.videoView);
        mediacontroller = new MediaController(MainActivity.this);

        mediacontroller.setAnchorView(resultvideo);

        resultvideo.setMediaController(mediacontroller);

        Button click = (Button)findViewById(R.id.buttonRecord);
        resultvideo = (VideoView)findViewById(R.id.videoView);

        final ImageView url = (ImageView) findViewById(R.id.imageView);
        Picasso.with(this).load("http://test.please.do/app/car.jpg").into(url);

        buttonLoad = (Button) findViewById(R.id.buttonLoad);
        {
            buttonLoad.setOnClickListener(new View.OnClickListener() {
                @Override
                public void onClick(View v) {

                    url.setVisibility(View.VISIBLE);
                }
            });
        }
    }

Answer 1

change

final ImageView url = (ImageView) findViewById(R.id.imageView);
    Picasso.with(this).load("http://test.please.do/app/car.jpg").into(url);

    buttonLoad = (Button) findViewById(R.id.buttonLoad);
    {
        buttonLoad.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {

                url.setVisibility(View.VISIBLE);
            }
        });
    }

to

final ImageView url = (ImageView) findViewById(R.id.imageView);

    buttonLoad = (Button) findViewById(R.id.buttonLoad);
        buttonLoad.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {             
Picasso.with(this).load("http://test.please.do/app/car.jpg").into(url);
            }
        });

and try to remove the code to make it invisible

Answer 2

If you use View.INVISIBLE , the view still take the space even if it is shown as transparent. If you want to totally hide the ImageView, you should use View.GONE .

The difference is simply that View.GONE collapse the view so the space is not left empty for her.

From the two links above:

View.INVISIBLE

This view is invisible, but it still takes up space for layout purposes.

View.GONE

This view is invisible, and it doesn't take any space for layout purposes. Se the two links for more informations

Edit

Another possible way could be adding by code the imageView after the button click.. Or another way could be setting height of the imageView to 0dp and then back to WRAP_CONTENT .

Those are possibilities, you can do it . But I highly reccoment using View.GONE and View.VISIBLE for handling stuffs like this since it is the "Standard" for View behaviours

Answer 3

You should add the image button after the old layout. like this:

<RelativeLayout ...>
    <variable..../>
    <ImageButton..../>
</RelativeLayout>