PropertyAnimation屬性動畫 ObjectAnimator三種方式實現

import android.animation.ObjectAnimator;
import android.animation.PropertyValuesHolder;
import android.animation.ValueAnimator;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.ImageView;

public class MainActivity extends AppCompatActivity {

    private Button but;
    private ImageView iv;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        but = (Button) findViewById(R.id.but);
        iv = (ImageView) findViewById(R.id.iv);
        but.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                //1. 直接定義實現屬性動畫
                //ObjectAnimator.ofFloat(iv, "rotationY", 0.0f, 50f).setDuration(1000).start();
                //2.自定義+監聽實現屬性動畫效果
//                ObjectAnimator animator = ObjectAnimator.ofFloat(iv,"bw",10.0f,360f).setDuration(3000);
//                animator.start();
//                animator.addUpdateListener(new ValueAnimator.AnimatorUpdateListener() {
//                    @Override
//                    public void onAnimationUpdate(ValueAnimator animation) {
//                        float anim = (float) animation.getAnimatedValue();
//                        iv.setTranslationX(anim);
//                        iv.setRotationX(anim);
//                    }
//                });
                //3.通過PropertyValuesHolder實現屬性動畫
                PropertyValuesHolder alpha = PropertyValuesHolder.ofFloat("alpha", 1.0f, 0.2f);
                ObjectAnimator.ofPropertyValuesHolder(iv,alpha).setDuration(1000).start();
            }
        });
    }
}