My launching activity consists of Linear layout with two buttons. Both buttons have listeners: the first one (b) moves itself upon click: 30px to the left and 30px back upon the next click. The second one (b2) changes its text upon click. Here is the code:
public class TestActivity extends Activity {
public final String TAG="TestActivity";
boolean toTop=true;
boolean setInitialText=false;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
Button b=(Button)findViewById(R.id.button);
Button b2=(Button)findViewById(R.id.button2);
b.setOnClickListener(new OnClickListener() {
public void onClick(View v) {
int modifier;
if(toTop) modifier=-30;
else modifier=30;
v.layout(v.getLeft()+modifier,v.getTop(),v.getRight()+modifier,v.getBottom());
toTop=!toTop;
}
});
b2.setOnClickListener(new OnClickListener() {
public void onClick(View v) {
String currentText;
if(setInitialText)currentText="Press to change text";
else currentText="Press to change back";
((Button)v).setText(currentText);
setInitialText=!setInitialText;
}
});
}
}
XML layout-file:
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:gravity="center"
android:orientation="vertical" >
<Button
android:id="@+id/button"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Press to begin animation" />
<Button
android:id="@+id/button2"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Press to change text" />
My problem: when b is moved to the left and I press b2, b moves to its initial position. Why? I don't want it to move back and didn't specify it anywhere.
It looks like View.layout looses its effect. Why it happens? I tested that in other situations and it seems that any UI update makes all invoked View.layout methods loose their effect.
In my main project there is a ListView which is populated with images from background - all view moves loose effect when new image appears. Besides, if I add EditText and try to enter something (as user), view moves loose their effect as well. Can anyone explain to me what's going on and why do views move back?
