单元测试

XML布局：

<TextView
    android:text="Hello World"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:id="@+id/textView2"/>

<Button
    android:text="Say Hello"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:id="@+id/button"
    android:layout_marginTop="41dp"
    android:layout_below="@+id/textView2"
    android:layout_alignparentStart="true"
    android:onClick="Say Hello"/>


<EditText
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:id="@+id/editText"
    android:layout_below="@+id/textView2"
    android:layout_alignparentStart="true"
    android:layout_alignparentEnd="true"
    android:text="huanying"/>

java代码：

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);
}
public SayHello(View v){
    TextView textView = (TextView)findViewById(R.id.textView);
    EditText editText = (EditText)findViewById(R.id.editText);
    TextView.setText("Hello,"+editText.getText().toString()+"!");
}


测试程序：

@Rule
public ActivityTestRule<MainActivity>mActivityRule = new ActivityTestRule<>(MainActivity.class);

@Text
public void sayHello(){
onView(withId(R.id.editText)).perform(typeText(STRING_TO_BE_TYPED),closeSoftKeyboard());
onView(withText("Say hello!")).perform(click());
String expectedText = "Hello,"+STING_TO_BE_TYPED+"!";
onView(withId(R.id.textView)).check(matches(withText(expectedText)));
}