View height and width are always zero

[christopherperry]

Failing test:

@Test
public void heightAndWidth_shouldNotBeZero() {
  TestActivity testActivity =
    Robolectric.buildActivity(TestActivity.class)
      .create().start().resume().visible().get();

  View contentView = testActivity.findViewById(69);
  assertThat(contentView.getWidth()).isNotZero();
  assertThat(contentView.getHeight()).isNotZero();
}

private static class TestActivity extends Activity {  
  @Override 
  protected void onCreate(Bundle savedInstanceState) {  
      super.onCreate(savedInstanceState);  
      LinearLayout contentView = new LinearLayout(this);  
      contentView.setId(69);    
      contentView.setLayoutParams(new LayoutParams(666, 666));
      setContentView(contentView);  
  }  
}  

[christopherperry]

Anyone have input on this? Seems like a major oversight to me.... but I guess this goes in with the same category as some of my other recent issues dealing with resource loading, and config stuff relating to screen size etc.

[erd]

Robolectric isn't trying to emulate Android - just fake enough of it so you can write reasonable unit tests.

It doesn't surprise me that views don't have a width or height, since we're not doing anything that would cause a layout pass to happen. What are you trying to test that requires your views to have been measured?

[christopherperry]

Hi @erd, I'm testing code for drag and drop, and the drag code implements bounding within the parent View hence it needs valid dimensions.

[ry4n1m3]

One workaround here is that you can manually call View.measure(int, int) and View.layout(int, int, int, int) on your content in your test.

[kingargyle]

Another option is to use Mockito to mock out the views and have the mocks return the values you would expect. Otherwise you are getting into more integration testing instead of unit testing.

[erd]

Thank you for the suggestion, but I don't think we're going to implement this.

[jpshelley]

@erd Do you have a good way to accomplish this? Would you recommend the mockito suggestion or the .measure and .layout approach?

[jongerrish]

Could we make Robolectric call into doTraversals() as part of the activity
life cycle?
On Apr 29, 2015 11:14 PM, "John Shelley" notifications@github.com wrote:

@erd https://github.com/erd Do you have a good way to accomplish this?
Would you recommend the mockito suggestion or the .measure and .layout
approach?

—
Reply to this email directly or view it on GitHub
#819 (comment)
.

[erd]

Would you recommend the mockito suggestion or the .measure and .layout approach?

I would go with the measure and layout approach if you really need to have your components sized / positioned correctly.

Could we make Robolectric call into doTraversals() as part of the activity life cycle?

It would make tests slower. Is it worth the trade-off?