Rotate animation android

问题:

I'm trying to do a rotating image animation. I need to rotate an icon around itself just like they do in a progressbar, but what I'm getting is an image rotating around a circle. Here is my animation code

<?xml version="1.0" encoding="utf-8"?>
<rotate
xmlns:android="http://schemas.android.com/apk/res/android"
android:fromDegrees="0"
android:toDegrees="360"
android:interpolator="@android:anim/linear_interpolator"
android:pivotX="50%"
android:pivotY="50%"
android:duration="2500"
android:repeatCount="infinite"
android:repeatMode="restart"
/>

Where am I going wrong in here? Thanks

回答1:

This is the source code for the layout main.xml:

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent" >

    <Button
        android:id="@+id/testButton"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="animationText" 
        android:onClick="AnimClick"/>

    <ImageView
        android:id="@+id/testImage"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_centerInParent="true"
        android:contentDescription="image_desc"
        android:scaleType="fitCenter"
        android:src="@drawable/cat2" />

</RelativeLayout>

To implement the rotation animation, we can define the animation by XML or Java code. If we want to write the animation in the xml, we need to create an animation xml file under /res/anim folder. Here, we create a xml file named rotate_around_center_point.xml

<?xml version="1.0" encoding="utf-8"?>
<set xmlns:android="http://schemas.android.com/apk/res/android"
    android:shareInterpolator="false" >

    <rotate
        android:duration="2500"
        android:interpolator="@android:anim/linear_interpolator"
        android:pivotX="50%"
        android:pivotY="50%"
        android:repeatCount="infinite"
        android:repeatMode="restart"
        android:toDegrees="360" />

</set>

and this is my Activity:

public class MainActivity extends Activity implements OnClickListener {

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        Button btn = (Button) findViewById(R.id.testButton);
        btn.setOnClickListener(this);

    }

    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        getMenuInflater().inflate(R.menu.activity_main, menu);
        return true;
    }

    @Override
    public void onClick(View v) {
        // TODO Auto-generated method stub
        ImageView animationTarget = (ImageView) this.findViewById(R.id.testImage);

        Animation animation = AnimationUtils.loadAnimation(this, R.anim.rotate_around_center_point);
        animationTarget.startAnimation(animation);

    }


}

回答2:

You could try with the following code, rather than doing it in XML:

RotateAnimation rotate = new RotateAnimation(0, 360,
        Animation.RELATIVE_TO_SELF, 0.5f, Animation.RELATIVE_TO_SELF,
        0.5f);

rotate.setDuration(4000);
rotate.setRepeatCount(Animation.INFINITE);
yourView.setAnimation(rotate);

回答3:

Well I got where I was wrong. I gave padding to my image which caused it to move aside a little every time it rotated. Anyhow I removed the padding and now it's working just fine.

回答4:

Add the following xml in the animation folder

<?xml version="1.0" encoding="utf-8"?>
<set xmlns:android="http://schemas.android.com/apk/res/android"
    android:shareInterpolator="false" 
    android:duration="4000" 
    android:fromdegrees="0" 
    android:pivotx="50%" 
    android:pivoty="50%"
    android:todegrees="360" 
    android:toyscale="0.0">
 </set>

Hope this will help you..

for more information http://www.blazin.in/2013/09/simple-rotate-animation-in-android.html