3.java

@Test 
public void testCleanData_input2plus2_allObjectsCleaned() { 
    assertNotNull(mMainActivity); 

    final Button addButton = mMainActivity.getAddButton(); 
    final EditText inputDataEditText = mMainActivity.getInputDataEditText(); 

    mMainActivity.runOnUiThread(new Runnable() { 
        @Override 
        public void run() { 
            inputDataEditText.setText(String.valueOf(2)); 
            addButton.performClick(); 
            inputDataEditText.setText(String.valueOf(2)); 
        } 
    }); 

    getInstrumentation().waitForIdleSync(); 

    assertEquals(inputDataEditText.getText().toString(), "2"); 
    assertEquals(mMainActivity.getTextResult(), "2.0 +"); 
    assertTrue(mMainActivity.mFirstValue == 2); 
    assertTrue(mMainActivity.mSecondValue == 0); 

    final Button cleanButton = mMainActivity.getCleanButton(); 

    mMainActivity.runOnUiThread(new Runnable() { 
        @Override 
        public void run() { 
            cleanButton.performClick(); 
        } 
    }); 

    getInstrumentation().waitForIdleSync(); 

    assertEquals(mMainActivity.getInputDataEditText().getText().toString(), ""); 
    assertEquals(mMainActivity.getTextResult(), ""); 
    assertTrue(mMainActivity.mFirstValue == 0); 
    assertTrue(mMainActivity.mSecondValue == 0); 
}