here is complete working example (works as outlined by author of accepted answer.)
Pressing the button toggles between 2 fragments A and B (by slide animation right to left). The fragments are just stupid text (AAAAAA and BBBBB) with different backgrounds.
MainActivity.java
package com.example.slidetrans;
import android.app.Activity;
import android.app.Fragment;
import android.app.FragmentManager;
import android.app.FragmentTransaction;
import android.os.Bundle;
import android.util.Log;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
public class MainActivity extends Activity {
private static final String TAG = "Main";
boolean showingA = true;
Button button;
A a;
B b;
private void incarnate(FragmentManager fm){
int layoutId = R.id.frame;
boolean fragmentWasNull = false;
Fragment f = fm.findFragmentById(layoutId);
if (f == null){
Log.i(TAG, "fragment is null");
if (showingA){
f = a = new A();
} else {
f = b = new B();
}
fragmentWasNull = true;
} else {
Log.i(TAG, "fragment is not null");
showingA = (f instanceof A);
updateButtonText();
}
if (fragmentWasNull){
FragmentTransaction ft = fm.beginTransaction();
ft.add(layoutId, showingA ? a : b, "main").commit();
}
}
private void updateButtonText(){
button.setText(showingA ? "slide in B" : "slide in A");
}
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
FragmentManager fm = getFragmentManager();
button = (Button)findViewById(R.id.button);
incarnate(fm);
OnClickListener listener = new OnClickListener() {
@Override
public void onClick(View v) {
FragmentManager fm = getFragmentManager();
FragmentTransaction transaction = fm.beginTransaction();
transaction.setCustomAnimations(R.anim.in, R.anim.out);
transaction.replace(R.id.frame, showingA ? new B() : new A()).commit();
showingA = !showingA;
updateButtonText();
}
};
button.setOnClickListener(listener);
}
}
LL.java
package com.example.slidetrans;
import android.content.Context;
import android.util.AttributeSet;
import android.widget.LinearLayout;
public class LL extends LinearLayout {
public LL(Context context) {
super(context);
}
public LL(Context context, AttributeSet attrs) {
super(context, attrs);
}
public float getXFraction() {
final int width = getWidth();
if (width != 0) return getX() / getWidth();
else return getX();
}
public void setXFraction(float xFraction) {
final int width = getWidth();
float newWidth = (width > 0) ? (xFraction * width) : -9999;
setX(newWidth);
}
}
main.xml (layout)
<?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:orientation="vertical"
>
<Button
android:id="@+id/button"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="slide in B" />
<FrameLayout
android:id="@+id/frame"
android:layout_width="match_parent"
android:layout_height="match_parent" >
</FrameLayout>
</LinearLayout>
a.xml (layout)
<?xml version="1.0" encoding="utf-8"?>
<com.example.slidetrans.LL xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical"
android:background="#00FF00"
>
<TextView
android:id="@+id/aText"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="AAAAAAAAAAAAAAAAAA"
android:textSize="30sp"
android:textStyle="bold"
/>
</com.example.slidetrans.LL>
b.xml (layout)
<?xml version="1.0" encoding="utf-8"?>
<com.example.slidetrans.LL xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical"
android:background="#FFFF00"
>
<TextView
android:id="@+id/bText"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:textSize="30sp"
android:textStyle="bold"
android:text="BBBBBBBBBB"
/>
</com.example.slidetrans.LL>
in.xml (anim)
<?xml version="1.0" encoding="utf-8"?>
<set xmlns:android="http://schemas.android.com/apk/res/android">
<objectAnimator
android:duration="500"
android:interpolator="@android:anim/linear_interpolator"
android:propertyName="xFraction"
android:valueFrom="1.0"
android:valueTo="0.0"
android:valueType="floatType" />
</set>
out.xml (anim)
<?xml version="1.0" encoding="utf-8"?>
<set xmlns:android="http://schemas.android.com/apk/res/android">
<objectAnimator
android:duration="500"
android:interpolator="@android:anim/linear_interpolator"
android:propertyName="xFraction"
android:valueFrom="0.0"
android:valueTo="-1.0"
android:valueType="floatType" />
</set>
